Purpose

The operational remote control system (SODC) is designed to continuously monitor the condition of the heat-insulating layer of polyurethane foam (PPU) before insulated pipes conductors during their entire service life. SODK is one of the main tools Maintenance pipelines built according to the "pipe in pipe" technology using signal copper conductors. The complex of instruments and equipment SODK allows you to timely and with great accuracy find the location of damage. The use of SODK contributes safe operation pipeline systems, allows you to significantly reduce the cost and time for repair work.

Principle of operation and organization of the system

The control system is based on the use of an insulation moisture sensor distributed along the entire length of the pipeline. Signal copper conductors (at least two) located in the heat-insulating layer of each pipeline element are connected along the entire length of the branched pipeline network into a two-wire line, combined at the end elements into a single loop. The conductors of any branches are included in the break of the signal conductor of the main pipeline. This loop of copper signal conductors, a steel pipe of all pipeline elements and a heat-insulating layer of rigid polyurethane foam between them form an insulation moisture sensor. The electrical and wave properties of this sensor allow:

1. Control the length of the humidification sensor or the length of the signal loop and, as a result, the length of the pipeline section covered by this sensor.

2. Monitor the moisture content of the heat-insulating layer of the pipeline section covered by this sensor.

3. Search for places of moistening of the heat-insulating layer or a break in the signal wire in the section of the pipeline covered by this sensor.

Monitoring the length of the moisture sensor is necessary to obtain reliable information about the state of humidity of the heat-insulating layer along the entire length of the pipeline section covered by this sensor. The length of the signal loop (the length of the humidity sensor) is defined as the ratio of the total resistance of the signal conductors connected in a closed circuit to their resistivity. The length of the pipeline section covered by this sensor is half.

When monitoring the state of humidity, the principle of measuring the electrical conductivity of the heat-insulating layer is applied. With an increase in humidity, the electrical conductivity of thermal insulation increases and the insulation resistance decreases. An increase in the humidity of the heat-insulating layer can be caused by the leakage of the heat carrier from the steel pipeline or the penetration of moisture through the outer shell of the pipeline.

The search for damage sites is carried out on the principle of pulse reflection (pulse reflectometry method). Humidification of the insulating layer or a wire break leads to a change in the wave characteristics of the insulation moisture sensor in specific local areas. The essence of the reflected pulse method consists in probing the line of signal conductors with high-frequency pulses. Determining the delay between the time of sending probing pulses and the time of receiving pulses reflected from inhomogeneities of wave impedances (wetting of the insulation or damage to signal conductors) makes it possible to calculate the distances to these inhomogeneities.

For operational work with the insulation dampening sensor, signal conductors and the “mass” of the steel pipe body from the heat-insulating layer are provided. These outputs are organized using special pipeline elements, in which the output of signal conductors is carried out by a cable passing through the outer insulation using a sealing device. These cables, brought to the technological premises, ground or wall carpets, together with the terminals connected to them, form control and switching points on the route - technological measuring points.

There are end and intermediate measuring technological points.

At the end measuring points, end elements of the pipeline with cable outlets are used. The cables from the supply and return pipes are connected to the end terminal installed in technological rooms or structures, ground or wall carpets.

At intermediate points, pipeline elements with an intermediate cable outlet are usually used. Cables from both pipelines are led to the ground carpet or process facilities and connected to an intermediate or double end terminal. But in places where thermal insulation is broken (in a thermal chamber, etc.), the organization of an intermediate measuring point is carried out using end elements with cable outlets. Cables from all elements of pipelines are brought out to the ground carpet or technological facility and connected to the corresponding terminal.

Technological measuring points installed at certain distances make it possible to quickly carry out search measurements with sufficient accuracy.

Part of the equipment

The control system is divided into the following parts: pipe, signal and additional devices.

The pipe part is all pipeline elements and components that directly form the insulation moisture sensor:

1. Piping elements with two or more copper signal conductors.
2. Intermediate and end cable outlets.
3. End elements of the pipeline.
4. Mounting and connecting kits for connecting signal conductors for waterproofing joints and for extending cable outlets.

Pipeline elements with two or more copper signal conductors are pre-insulated pipes, bends, compensators, tees, Ball Valves, etc.

The signal conductors installed inside the PPU insulation of each element are located parallel to the steel heat-carrying pipe at a distance of 16÷25 mm. from her. When assembling pipes, conductors are fixed in polyethylene sheath centralizers, which are installed at a distance of 0.8÷1.2 m from each other. These conductors are made from copper wire section 1.5 mm 2 (mark MM 1.5).

In all elements, the wires of the control system are located in the position “ten minutes to two hours”.

The end cable outlet is installed at the end of the thermal insulation. Structurally, it can be performed in two versions.

The first option is the end element of the pipeline with a cable outlet and a metal insulation plug (ZIM KV). In this element, two wires of a three-core cable are connected to the signal conductors at the end of the pipe, the third wire is connected to the steel pipe, and the cable is led out through the sealing device installed on the insulation plug. This option is used to bring the signal conductors inside engineering structures and technological premises.

The second option is the end element of the pipeline with a metal insulation plug and a cable outlet (KV ZIM). In this element, two wires of a three-core cable are included in the break of the main signal wire, the third wire is connected to a steel pipe, and the cable is led out through a sealing device installed on the pipe sheath. This option is used to output signal conductors to special technological devices (carpets) installed outside engineering structures and buildings.

Intermediate cable outlets are designed to divide an extensive pipeline network into sections of a certain length, which provides the necessary accuracy when troubleshooting the control system. They are installed along the length of the route through distances determined by the regulatory documentation (SP 41-105-2002) and agreed with the operating organizations. The intermediate cable exit is made in the form of a special element of the pipeline, in which four wires of a five-core cable are included in the gap of the signal wires, the fifth wire is connected to the working pipe, and the cable itself is output through a sealing device installed on the pipe sheath.

The end elements of the pipeline are installed at the end of the thermal insulation and are designed to combine a two-wire line into a single loop and protect the thermal insulation layer from moisture penetration. The connection of the signal conductors to each other at the end elements of the pipeline is made along the end face of the insulating layer under the insulation plug.

The insulation resistance of each signal conductor of any element is at least 10 MΩ.

Mounting and connection kits

The SODK wire connection kit (included in the kits for sealing butt joints) is designed to connect the SODK wires and fix them on the heat-carrying pipe at a certain distance from it.

Delivery set for 1 joint:

1. wire holder - 2 pcs.
2. crimp sleeve for connecting wires - 2 pcs.

1. solder, quantity per 1 joint - 2g
2. flux or solder paste - 1g
3. adhesive tape - according to the table:

Outer diameter of steel pipe	Consumption of tape with an adhesive layer per 1 joint
d, mm	m
57	0,5
76	0,7
89	0,85
108	1,02
133	1,26
159	1,5
219	2,1
273	2,6
325	3,1
377	3,55
426	4,05
530	5,02

The 3-core output cable extension kit is used to extend the 3-core cable UEC systems at the end cable outlets during pipeline installation.

Contents of delivery:

Three-core cable - 5 m;

Heat shrink tube with a diameter of 25 mm L= 0.12 m;

Mastic tape "Guerlain" - 0.2 m 2;

Insulating tape - 1 roll for 10 sets;

Crimp sleeve for connecting wires - 3 pcs;

Heat shrink tube with a diameter of 6 mm L = 3 cm - 3 pcs;

Consumables (not included in the package):

Solder - 3g.
- flux or solder paste - 1.5 g.

Five-core cable extension kit output used to extend the five-core cable of the UEC system at the intermediate cable outlet during pipeline installation.

Contents of delivery:

Five-core cable - 5 m;

Heat shrink tube with diameters 25 mm - 0.12 m;

Mastic tape "Guerlain" - 0.2 m 2;

Insulating tape - 1 roll 1 - 8 sets;

Crimp sleeve for splicing wires - 5 pcs.

Heat shrink tube diameter - 6 mm L= 3cm - 5 pcs

Consumables (not included in the package):

Solder - 5g.
- flux or solder paste - 2.5 g.

signal part consists of interface elements and devices:

1. Measuring and switching terminals for connecting devices at control points and switching signal conductors.
2. Control devices (detectors, indicators) are portable and stationary.
3. Fault location devices (pulse reflectometer).
4. Measuring instruments (insulation tester, megohmmeter, ohmmeter).
5. Cables for mounting connection of terminals and connection of terminals with stationary control devices.

For switching signal conductors and connecting devices to connecting cables at control and switching points, special junction boxes - terminals are used.

Terminals are divided into two main types: measuring and sealed.

Measuring terminals are designed for operational switching of signal conductors during measurements. The necessary switching and measurements are carried out using external plug connectors, without opening the terminal. Terminals of this type are installed in dry or well-ventilated engineering devices (ground or wall carpets, etc.) and technological rooms (central heating centers, ITPs, etc.).

Sealed terminals are designed for switching signal conductors in high humidity conditions. The necessary switching and measurements are made using connectors installed inside the terminals. Removing the terminal cover is required to access them. Terminals of this type can be installed in any technological devices (ground or wall carpets, etc.), structures and premises (in thermal chambers, in basements, etc.)

Types of measuring terminals:

End terminal (KT-11, KIT, KSP 10-2 and TKI, TKIM) - installed at control points at the ends of the pipeline;

End terminal with access to a stationary detector (KT-15, KT-14, IT-15, IT-14, KDT, KDT2, KSP 12-5 and TKD) - is installed at the end of the pipeline, at the control point, where a stationary detector is connected ;

Intermediate terminal (KT-12/Sh, IT-12/Sh, PIT, KSP 10-3, TPI and TPIM) - is installed at intermediate pipeline control points and at control points at the beginning of side branches.

Double end terminal (KT-12/Sh, IT-12/Sh, DKIT, KSP 10-4 and TDKI) - installed at the control point on the border of separation of control systems of associated projects;

Types of sealed terminals:

The end terminal is sealed - installed at the control points at the ends of the pipeline;

Intermediate terminal (KT-12, IT-12, PGT and TPG) - is installed at intermediate pipeline control points and at control points at the beginning of side branches.

The unifying sealed terminal (CT-16, IT-16, OT6, OT4, OT3, KSP 13-3, KSP 12-3, TO-3 and TO-4) is installed at those control points where it is necessary to combine several pipeline sections or several separate pipelines;

The unifying sealed terminal with access to a stationary detector (KT-16, IT-16, OT6, OT3, KSP 13-3, KSP 12-3 and TO-3) is installed at the control point where it is necessary to combine several separate pipelines into a single loop , and which provides for the connection of a cable from a stationary detector;

The sealed through terminal (KT-15, IT-15, PT, KSP 12 and TP) is installed in places of rupture of PPU insulation (in thermal chambers, in basements of houses, etc.) for switching connecting cables or arranging an additional control point when the need to use long connecting cables.

Compliance of terminals manufactured by NPK VECTOR, LLC TERMOLINE, NPO STROPOLYMER, CJSC MOSFLOWLINE and terminals of the TermoVita series

OOO "TERMOLINE"	NPC "VECTOR"		NGOs "STROYPOLYMER"	CJSC "MOSFLOWLINE"
CT-11	IT-11	WHALE	KSP 10-2	End terminal.
KT-12	IT-12	PGT	No	----
KT-12/Sh	IT-12/Sh	PIT, DKIT	KSP 10-3, KSP 10-4	Intermediate terminal, double end terminal
CT-13	IT-13	KGT	KSP 10	----
KT-15	IT-15	KDT	KSP 12-5	Terminal with detector access
KT-14	IT-14	KDT2	KSP 12-5 (2 pieces)	Terminal with detector access (2 pieces)
KT-15	IT-15	Fri, OT4	KSP 12	Checkpoint terminal
KT-15/Sh	IT-15/Sh	KIT4	KSP 12-2, KSP 12-4	----
KT-16	IT-16	OT6, OT3 (2 pieces)	KSP 13-3, KSP 12-3 (2 pieces)	__

The terminals are connected to the UEC conductors using connecting cables: a 3-core cable (NYM 3x1.5) for connecting terminals at the end sections of the heating main and a 5-core cable (NYM 5x1.5) for connecting terminals at intermediate sections of the heating main. Connection and operation of the terminals is carried out in accordance with the technical documentation of the manufacturer.

Control devices

Monitoring the state of the UEC system during the operation of pipelines is carried out using a device called detector. This device records the electrical conductivity of the heat-insulating layer. When water enters the heat-insulating layer, its conductivity increases and this is recorded by the detector. At the same time, the detector measures the resistance of conductors connected in a closed circuit.

The detectors can be powered from a 220 Volt mains (stationary) or from an autonomous power source of 9 Volts (portable).

Stationary detector allows you to simultaneously control two pipes with a maximum length of 2.5 to 5 km each, depending on the model.

Table 1

Technical characteristics of stationary detectors

Options	Vector-2000	PICCON				SD-M2
		DPS-2A	DPS-2AM	DPS-4A	DPS-4AM
Supply voltage, V	220 (+10-15)%	220 (+10-15)%				220 (+10-15)%
Number of controlled sections of pipelines, pcs.	1 to 4	2		4		2
	up to 2500	up to 2500				5000
	over 600	over 200				over 150
Insulation wet indication, kOhm	less than 5 (+10%)	less than 5 (+10%)				Multi-level more than 100 30 to 100 10 to 30 3 to 10 less than 3
	10 DC	8 DC				4 AC
	30	30				120 (2 Tues)
Operating ambient temperature, С ˚	-45 - +50	-45 - +50		-45 - +50		-40 - +55
	no more than 98 (25 °С)	45÷75		45÷75		No data
Protection class against external influences		IP 55		IP 55		IP67
Overall dimensions, mm	145x220x75	170x155x65		220x175x65		180x180x60
Weight, kg	no more than 1	no more than 0.7		no more than 1		0,75

When using the stationary detector SD-M2, it is possible to organize a centralized SODK of an extensive heating network of considerable length (up to 5 km) from a single control room. To do this, the stationary detector has contacts with galvanic isolation for each channel, which are closed in the event of a malfunction.

Connection and operation of stationary detectors is carried out in accordance with the technical documentation of the manufacturer.

The portable detector allows you to monitor a pipe with a maximum length of 2 to 5 km, depending on the model. One detector can control different areas pipelines that are not interconnected into a single system. A portable detector is not permanently installed at the facility, but is connected to the controlled area by an employee who conducts a survey in the order of operation.

table 2

Specifications for portable detectors

Options	Vector-2000	PICCON DPP-A	PICCON DPP-AM	DA-M2
Supply voltage, V	9	9		9
Length of one controlled pipeline section, m	before 2000	before 2000		5000
Indication of damage to signal wires, Ohm	over 600(+10%)	over 200(+10%)		150
Control voltage on signal wires, V	10 DC	8 DC		4 AC
PPU-insulation wetting indication, kOhm	less than 5 (+10%)	less than 5 (+10%)	Multilevel more than 1000 500 to 1000 100 to 500 50 to 100 5 to 50	Multi-level more than 100 30 to 100 10 to 30 3 to 10 less than 3
Current consumption in operating mode, mA	1,5	1,5		no more than 20
Operating ambient temperature, "FROM	-45 - +50	-45 - +50		-20 - +40
Operational humidity of the environment, %	no more than 98 (25 °С)	45÷75		Splash-proof
Overall dimensions, mm	70x135x24	70x135x24		135x70x25
Weight, g	no more than 100	no more than 170		150

Connection and operation of portable detectors is carried out in accordance with the technical documentation of the manufacturer.

Damage detectors

Used to locate damage. pulse reflectometer, providing acceptable measurement accuracy. The reflectometer allows you to determine the damage at distances from 2 to 10 km, depending on the model used. The measurement error is approximately 1-2% of the length of the measured line. The accuracy of measurements is determined not by the error of reflectometers, but by the error of the wave characteristics of all elements of the pipeline (the wave resistance of the insulation moisture sensor). Depending on the moisture content of the insulation, the reflectometer allows you to locate several places with reduced insulation resistance.

Technical characteristics of domestic pulse reflectometers

Name	FLIGHT-105	FLIGHT-205	RI-10M	RI-20M
manufacturer	NPP STELL, Bryansk		ZAO ERSTED St. Petersburg
Range of measured distances	12.5 -25600 m	12.5-102400m	1- 20000 m	1m-50km.
Resolution	Not worse than 0.02 m	0.2% on the bands from 100 to 102400 m	1% of range	25 cm ... 250 m. (in range)
Measurement error	Less than 1%	Less than 1%	Less than 1%	Less than 1%
output impedance	20 - 470 Ohm continuously adjustable	from 30 to 410 continuously adjustable	20 - 200 Ohm.	thirty. . 1000 ohm.
Sounding signals	Pulse amplitude 5 V, 7 ns - 10 μs;	Pulse amplitude 7 V and 22 V from 10 to 30-10 3 ns	Pulse amplitude 6 V, 10 ns - 20 μs;	Pulse with an amplitude of at least 10 V. 10 ns. .50 µs.
Stretching		Ability to stretch the trace around the measuring or zero cursor by 2,4,8, 16, ... 131072 times	0.1 from range	0.025 off range
Memory	200 reflectograms;	up to 500 reflectograms	100 reflectograms	16 MB.
Interface	RS-232	RS-232	RS-232	RS-232
Gain	60 dB	86 dB	-20...+40 dB.	-20...+40 dB.
KU setting range (v/2)	1.000...7.000	1.000...7.000		1.00...3.00 (50 m/µs... 150 m/µs).
Display		LCD 320x240 dots with backlight	LCD 128x64 dots with backlight	LCD 240x128 dots with backlight
Food	built-in battery - 4.2÷6V network - 220÷240 V, 47-400 Hz DC network - 11÷15V	built-in battery - 10.2-14 DC network - 11÷15V network - 220÷240	built-in battery - 12 V; mains - 220V 50Hz, via adapter Time continuous work from the accumulator not less than 6 hour (with illumination).	built-in battery - 12 V; mains - 220V 50Hz, through an adapter Time of continuous operation from the battery is not less than 5 hours (with backlight).
Power consumption	2.5 W or less	5 W	3 VA	4VA
Operating temperature range	- 10 °С + 50 °С	- 10 °С + 50 °С	-20С...+40С	-20С...+40С
dimensions	106x224x40mm	275x166x70	267x157x62	220x200x110 mm
Weight	Less than 0.7 kg (with built-in batteries)		Less than 2 kg (with built-in batteries)	no more than 2.5 kg (with built-in batteries)

FLIGHT-205

Reflectometer REIS-205 along with the traditional by pulse reflectometry, which reliably and accurately determines the length of the line, the distance to places short circuit, breakage, low-resistance leakage and longitudinal increase in resistance (for example, in places of twisting of cores, etc.), additionally implements m skeletal measurement method.What lets with high precision measure the loop resistance, ohmic asymmetry, line capacitance, insulation resistance, determine the distance to the place of high-resistance damage (lower insulation) or line break.

Connection and operation of pulse reflectometers is carried out in accordance with the technical documentation of the manufacturer.

Additional devices

Ground and wall carpets

Purpose

The carpet, both ground and wall, is designed to accommodate switching terminals and protects the elements of the control system from unauthorized access.

The carpet is a metal structure with a reliable locking device. Inside the carpet there is a place for attaching the terminal.

Design

System design must be carried out with the possibility of connecting the designed system to the control systems of existing pipelines and pipelines planned in the future. The maximum length of an extensive network of pipelines for the designed control system is selected based on the maximum range of control devices (five kilometers of the pipeline).

The choice of the type of control devices for the designed section should be made based on the possibility of supplying (availability) voltage of 220 V to the designed section for the entire period of operation of the pipeline. In the presence of voltage, it is necessary to use a stationary fault detector, and in the absence of voltage, a portable detector with independent power supply.

The choice of the number of devices for the designed section should be made taking into account the length of the designed section of the pipeline.

If the length of the designed section is greater than the maximum length controlled by one detector (see the characteristics in the passport), then it is necessary to divide the heating main into several sections with independent control systems.

The number of plots is determined by the formula:

N= Lnp/Lmax,

where /_ pr is the length of the designed heating main, m;

L^ ax - maximum range of the detector, m.

The resulting value is rounded up to the next whole number.

Note. One portable detector can control several independent sections of heating networks.

Test points are intended to allow operating personnel to access signal wires in order to determine the condition of the pipeline.

Control points are divided into end and intermediate. End control points are located at all end points of the pipeline being designed. With a section length of less than 100 meters, only one control point is allowed, with signal conductors looped under a metal plug at the other end of the pipeline.

Control points are located in such a way that the distance between two adjacent control points does not exceed 300 m. At the beginning of each side branch from the main pipeline, if its length is 30 m or more (regardless of the location of other control points on the main pipeline), an intermediate terminal is placed .

At the boundaries of the associated heat network projects, at the points of their connection, it is necessary to provide control points and install double end terminals that allow you to combine or disconnect the UEC system of these sections.

When the conductors of the UEC system are connected in series at the ends of the insulation (the passage of pipelines through thermal cameras, cellars of buildings, etc.) connection of conductors must be carried out only through terminals.

The maximum cable length from the pipeline to the terminal should not exceed 10 m. If a longer cable length is required, an additional terminal must be installed as close as possible to the pipeline.

Each control point should include:

• pipeline element with output cable;
• connection cable;
• switching terminal.

It is not recommended to place control points in thermal chambers due to humidity in the chamber, however, it is allowed only in cases where the placement of the ground carpet is associated with any difficulties (damage appearance cities, impact on traffic safety, etc.). In these cases, the terminals placed in the thermal chambers must be airtight. In the basements of houses, the placement of control points is not recommended if the designed heating main and the house belong to different departments, since in these cases a conflict is possible during the operation of pipelines (due to problems with access to control points and the safety of the elements of the UEC system). In these cases, it is recommended to equip the control point with a ground carpet installed 2 - 3 meters from the house.

Installation of terminals at intermediate and end points of control is carried out in ground or wall carpets of the established sample. At the end points of the pipeline, it is allowed to install terminals in the central heating station.

Design rules for control systems

(in accordance with SP 41-105-2002)

1. As the main signal wire, a marked wire is used, located on the right in the direction of water supply to the consumer on both pipelines (conditionally tinned). The second signal conductor is called transit.
2. The conductors of any branches must be included in the break of the main signal conductor of the main pipeline. Do not connect side branches to copper wire located on the left along the water supply to the consumer.
3. When designing conjugated projects, intermediate cable outlets with double end terminals are installed at the junctions of the routes, which allow you to combine or disconnect the control systems of these projects.
4. At the ends of the routes of a single project, end cable outlets with end terminals are installed. One of these terminals may have an output to a stationary detector.
5. Along the entire route through distances not exceeding 300 meters, intermediate cable outlets with intermediate terminals are installed.
6. Intermediate cable outlets on heating mains should be additionally installed on all side branches longer than 30 meters, regardless of the location of other terminals on the main pipe.
7. The control system should provide measurements from both sides of the controlled area with its length of more than 100 meters.
8. For pipelines or end sections with a length of less than 100 meters, it is allowed to install one end or intermediate cable outlet and the terminal corresponding to it. At the other end of the pipeline, the line of signal conductors is connected in a loop under the metal insulation plug.
9. When connecting signal conductors in series, at the end of PPU insulation (passage through chambers, basements of buildings, etc.), as well as when combining control systems for different pipes (supply from return, heating network with hot water supply), connect cables between pipeline sections only with feed-through, bridging or sealed terminals.
10. The specification must indicate the length of the cable for a specific point, taking into account the depth of the heating main, the height of the carpet, the distance of its (carpet) removal to the mainland soil and 0.5 meters of margin.
11. The maximum cable length from the pipeline to the terminal should not exceed 10 meters. In the event that it is required to use a cable with a longer length, it is necessary to install an additional feed-through terminal. The terminal is installed as close as possible to the pipeline.
12. Installation of stationary detectors on pipelines that enter process rooms with constant access service personnel, required.

Diagram of the control system

The control system diagram consists of a graphic representation of the signal conductors connection diagram, repeating the route configuration.

The diagram shows:

F installation locations of cable outlets and control points indicating the types of terminals, detectors and types of carpets (ground or wall) in graphical form;

F are indicated conventions all elements used in the control system diagram;

F, the characteristic points corresponding to the wiring diagram are indicated: branches from the main trunk of the heating main (including drains); turning angles; fixed supports; diameter transitions; cable outlets.

The scheme is accompanied by a data table on characteristic points indicating the following parameters:

F numbers of points according to design documentation;

F pipe diameter in the section;

F is the length of the pipeline between points according to the design documentation for the supply pipeline;

F is the length of the pipeline between points according to the design documentation for the return pipeline;

F length of the pipeline between points according to the joint scheme (separately for the main and transit signal conductors of each pipeline);

F length of connecting cables at all control points (separately for each pipeline).

Additionally, the control scheme should contain:

F diagrams for connecting connecting cables to signal conductors;

F wiring diagrams for terminals and fixed detectors;

F specification of the instruments and materials used;

F sketches of markings of external and internal connectors in directions.

The design of the control system must be agreed with the organization that accepts the heating main for balance.

Installation of the UEC system

Installation of the UEC system is carried out after welding of pipes and hydraulic testing of the pipeline.

When installing pipeline elements at a construction site, before welding the joint, the pipes must be oriented in such a way as to ensure that the wires of the UEC system are located along the side parts of the joint, and the wire leads of one pipeline element are located opposite the leads of the other, thereby providing the opportunity connecting wires over the shortest distance. Signal wires must not be placed at the bottomquarter joint.

At the same time, the mounted elements of the pipeline are checked for the condition of the insulation (visually and electrically) and the integrity of the signal conductors. And all elements of the pipeline with cable outlets require an additional measurement of the circuit of the yellow-green wire of the output cable and the steel pipe. The resistance should be ≈ 0 ohm.

During welding, the ends of the polyurethane foam insulation should be protected with removable aluminum (or tin) screens to prevent damage to the signal wires and the insulating layer.

During the installation work carry out accurate measurements of the lengths of each element of the pipeline (for a steel pipe), with the results recorded on the executive diagram of butt joints.

Connection of signal conductors is made strictly according to the design scheme of the control system.

The conductors of any branches must be included in the break of the main signal conductor of the main pipeline. It is forbidden to connect side branches to the copper wire located on the left in the direction of water supply to the consumer.

As the main signal wire, a marked wire is used, located on the right in the direction of water supply to the consumer on both pipelines (conditionally tinned).

Signal conductors of adjacent elements of pipelines must be connected by means of crimp sleeves, followed by soldering of the junction of the conductors. Crimp sleeves with inserted wires only special tool(crimping pliers). Crimping should be done with the middle working part of the tool marked 1.5. It is forbidden to crimp the crimp sleeves with non-standard tools (nippers, pliers, etc.)

Soldering must be done using inactive fluxes. Recommended flux LTI-120. Recommended solder POS-61.

When connecting wires at the joints, all signal wires are fixed on wire holders (racks), which are attached to the pipe with adhesive tape (adhesive tape). The use of chlorine-containing materials is prohibited. It is also forbidden to let the insulation over the wires, fixing the racks and wires at the same time.

When installing pipeline elements with cable outlets, mark the free end of the signal cable from the supply pipeline with insulating tape.

Minstallation of conductors of the UEC system duringjoint insulation works

1. Before installing the signal wires, the steel pipe is cleaned of dust and moisture. The polyurethane foam at the ends of the pipe is cleaned: it must be dry and clean.

3. Straighten the wires.

4. Cut the wires to be connected, having previously measured the required length. Clean the wires with sandpaper.

5. Connect the wires at the opposite end of the piping element or installed section and check them for a short to the pipe.

6. Connect both wires to the device and measure the resistance: it should not exceed 1.5 Ohm per 100 m of wires.

7. Clean the section of the steel pipe from rust and scale. Connect one instrument cable to the pipe, the other to one of the signal conductors. At a voltage of 250 V, the insulation resistance of any pipeline element must be at least 10 MΩ, and the insulation resistance of a 300 m long pipeline section must not be less than 1 MΩ. With an increase in the length of the conductors, their resistance will decrease. The actual measured insulation resistance must not be less than the value determined by the formula:

Rfrom = 300/ Lfrom

Rfrom- measured insulation resistance, MΩ

Lfrom- length of the measured section of the pipeline, m.

If the resistance is too low, it indicates that the insulation is too damp or that there is contact between the signal wires and the steel pipe.

8. Fix the wires at the joint using standoffs and adhesive tape. It is forbidden to put adhesive tape over the wires, fixing the racks and wires at the same time.

9. Connect the wires according to the instructions "Connecting the conductors of the UEC system".

10. Perform thermal and waterproofing of the joint. The type of thermal and waterproofing is determined by the project.

11. Upon completion of work, check the insulation resistance and the resistance of the loops of the wires of the UEC system of the mounted sections. Record the measurement results in the "Journal of Work".

If the signal wire breaks at the exit from the insulation, you need to remove the PPU insulation around the broken wire in an area sufficient for a reliable connection of the wires. The connection is made using crimp sleeves and soldering. Build short wires in the same way.

When installing the wires of the signal system, at each joint, the signal circuit and insulation resistance are monitored in accordance with the diagram below:

After waterproofing, check the insulation resistance and the resistance of the wire loops of the UEC system of the installed sections, and enter the obtained data into the act of work performed or the measurement protocol.

Control measurements of system parametersthemes of the JDCon pipeline elements

1. Straighten the wire leads and lay them so that they are parallel to the pipe. Carefully inspect the wires - they should not have cracks, cuts and burrs. When measuring at cable outlets, remove the outer insulation of the cable at a distance of 40 mm. from its end and the insulation of each core by 10-15 mm. Clean the ends of the wires with an emery cloth until a characteristic copper sheen appears.

2. Short-circuit two wires at one end of the pipe. Make sure that the contact between the wires is reliable and the wires do not touch the metal pipe. Perform similar operations to check the wires in the taps. For T-branches, the wires must be closed at both ends of the main pipe, forming a single loop. At the end of the pipeline section with an element with a cable outlet, connect the corresponding cable cores leaving in one direction.

3. Connect an insulation resistance and continuity tester (STANDARD 1800 IN or similar) to the conductors at the open end and measure the resistance of the wires: the resistance should be in the range of 0.012-0.015 ohms per meter of conductor.

4. Clean the pipe, connect one of the device cables to it, connect the second cable to one of the wires. At a voltage of 500 V, if the insulation is dry, the device should show infinity. Permissible insulation resistance of each pipe or other pipeline element must be at least 10 MΩ.

5. When measuring the insulation resistance of a pipeline section consisting of several elements, the measuring voltage should not exceed 250 V. The insulation resistance is considered satisfactory at a value of 1 MΩ per 300 meters of the pipeline. When measuring the insulation resistance of pipeline sections with different lengths, it should be taken into account that the insulation resistance is inversely proportional to the length of the pipeline.

Installation of control points

Ground covers are installed on the mainland next to the pipeline at the points indicated on the control system diagram. The installation location of the ground carpet at a particular point is determined by the construction organization, taking into account the convenience of maintenance. The internal volume of the ground carpet must be covered with dry sand from the base to a level of 20 centimeters from the top edge.

After installing the carpet, its geodetic binding is carried out. When installing carpets on heating mains laid in bulk soils, additional measures should be taken to protect the carpet from subsidence and damage to the signal cable.

When installing a carpet on heating mains laid in bulk soils, it is necessary to provide additional measures to protect the carpet from soil subsidence.

The outer surface of the carpet is protected by an anti-corrosion coating.

The wall carpet is attached to the wall of the building, either from the outside or from the inside. The wall carpet is fixed 1.5 meters from a horizontal surface (the floor of a building, a chamber or the ground).

Connecting cables from pipeline elements with a sealed cable outlet to the carpet are laid in pipes (galvanized, polyethylene) or in a protective corrugated hose. The laying of the connecting cable inside the buildings (structures) to the installation site of the terminals must also be carried out in galvanized pipes or in protective corrugated hoses that are fixed on the walls. It is possible to use PE pipes. The laying of the connecting cable in the place where the thermal insulation is broken (in a thermal chamber, etc.) must also be carried out in a galvanized pipe fixed to the wall.

Mount terminals and detectors in accordance with the markings on the attached diagrams and accompanying documentation for these products.

Upon completion of the installation, mark the nameplates (tags) on each terminal according to the sketches for marking the connectors in directions.

On the inside of the cover of each carpet, weld the project number and the number of the point where this carpet is installed.

Upon completion of work, check the insulation resistance and the resistance of the wire loops of the UEC system and draw up the measurement results in an act of examining the parameters of the control system. In the same act, the lengths of the signal lines of each section of the pipeline and connecting cables at each measuring point, separately for the supply and return pipelines, should be recorded. Measurements should be taken with the detector turned off.

Acceptance of the UEC system into operation.

Acceptance of the AEC system should be carried out by representatives of the operating organization. In the presence of representatives of technical supervision, a construction organization and an organization that installed and adjusted the UEC system during a comprehensive check, the following are performed:

Measurement of ohmic resistance of signal conductors;

Measurement of insulation resistance between signal conductors and working tube;

Recording reflectograms of heating network sections using a pulsed reflectometer for use as a reference during operation. It is recommended to create a primary data bank by taking reflectograms of each wire between the nearest measuring points from opposite directions;

The correctness of the settings of control devices (locators, detectors) transferred into operation for this object.

All measurement data and initial information (length of pipelines, lengths of connecting cables at each control point, etc.) are recorded in the act of acceptance of the UEC system.

The UEC system is considered operational if the insulation resistance between the signal conductors and the steel pipeline is not lower than 1 MΩ per 300 m of the heating main. To control the insulation resistance, a voltage of 250V should be used. The loop resistance of the signal conductors must be between 0.012 and 0.015 ohms per meter of conductor, including connecting cables.

Rules for the operation of UEC systems.

For the prompt detection of faults in the UEC systems, it is necessary to ensure regular monitoring of the state of the system.

The control of the state of the UEC system should be carried out constantly by a stationary detector. Portable detectors are used only in sections of heating mains where it is not possible to install a stationary detector (no 220 V network) or during production repair work. During the repair work, the control system of the repaired area between the nearest measuring points is removed from the general system. General system control is divided into local areas. For the period of repair, the control of the state of the UEC system of each of these sections, separated from the stationary detector, is carried out by a portable detector.

Monitoring the state of the UEC system includes:

1. Monitoring the integrity of the loop of signal conductors.

2. Control of the state of insulation of the controlled pipeline.

If a malfunction of the AEC system (break or humidification) is detected, it is necessary to check the presence and correct connection of the terminal connectors at all control points, and then re-measure.

When confirming malfunctions of the UEC systems of heating mains that are under the guarantee of the construction organization (the organization that installs, adjusts and commissions the UEC system), the operating organization notifies the construction organization of the nature of the malfunction, which searches for and determines the cause of the malfunction.

Search for damage sites

The search for damage sites is carried out on the principle of pulse reflection (pulse reflectometry method). The signal wire, the working pipe and the insulation between them form a two-wire line with certain wave properties. Humidification of the insulation or a wire break leads to a change in the wave characteristics of this two-wire line. Troubleshooting of the control system is carried out instrumentally using a pulse reflectometer and a megohmmeter in accordance with the technical documentation for these devices. These works consist of the following stages:

1. A single section of the pipeline is determined with a break in the signal wire or with a reduced insulation resistance using an indicator (detector) or a megohmmeter. Under a single section, a section of the heating network between the nearest measuring points is taken.

2. The wires of the UEC system are decommutated in a dedicated area.

3. Next, the reflectograms of each wire are taken separately from opposite directions. If there are primary reflectograms taken during the delivery of the AEC system, they are compared with the newly obtained reflectograms.

4. The received data is superimposed on the joint scheme. That is, the ratio of distances according to reflectograms with the distances available on the joint diagram is made.

5. Based on the results of the data analysis, the pipeline is excavated for repair work. After excavation, it is possible to carry out control openings of the insulation in the area where the signal wires pass in order to remove clarifying information.

Types of malfunctions fixed by the control system on pipelines with PPUinsulation.

A. Broken signal wire

According to the parameters of the system, the ODK is characterized by the absence or increased value of the loop resistance.

1. Mechanical damage to the outer insulation of pipelines and connecting cables.

2. Fatigue breakage of signal wires during thermal cycles in places mechanical influences(cuts, breaks, pulling, etc.)

3. Oxidation of the junctions of signal wires inside the external insulation of pipelines and in the places of connection or extension of connecting cables (lack of soldering, overheating of the solder joint, the use of active fluxes without flushing the joint.)

4. Switching breaks at the terminals (defects in solder joints, oxidation, deformation and fatigue of spring contacts of switching connectors, loosening of screw terminals of connecting blocks).

B. Wetting of polyurethane foam insulation.

According to the parameters of the system, the UEC is characterized by a reduced insulation resistance.

1. Leakage of external insulation.

a. Mechanical damage to external insulation and connecting cables (bursts and breakdowns).

b. Defects in the welds of the polyethylene sheath of fittings (not penetration, cracks).

in. Leakage of joint insulation (no penetration, lack of adhesion of adhesive materials).

2. Internal wetting.

a. Defects in welded seams of steel pipes.

b. Fistulas from internal corrosion.

C. Shorting the signal wire to the pipe.

According to the parameters of the system, the UEC is characterized by a very low insulation resistance.

The reasons:

Destruction of the PPU film between the pipe and the signal wire during thermal cycles. A manufacturing defect is the approach of the wire to the pipe. Detection is not difficult and is carried out similarly to the search for places of moisture.

PSK Polistroy, in addition to manufacturing products with PPU, provides services for insulating joints on a heating main, installation and commissioning of the UEC system, delivery of the UEC system at the facility of the operating organization, diagnostics and repair.

Insulation of joints on the heating main

Steel has already proven its effectiveness in our country. The most “thin” moment when laying them is the insulation of the joints. The pipe itself is protected from corrosion at the factory, but the joints require good sealing. Even if groundwater does not reach the surface of the pipe, dew can fall on it during a heat cut. Moisture will enter through the joint, and the entire pipe will corrode.

The better the isolation, the less chance of an emergency. The most efficient connection method is the use of couplings. We offer heat-shrinkable, electro-welded, galvanized sleeves, as well as hot-melt adhesives and foam kits.

We isolate the joints of pipes with a diameter of 110 to 1600 mm.

Installation and commissioning of the UEC (SODK) system

The UEC system helps to control the state of the heat-insulating layer of the heating network and detect places of moisture. This system works not only during operation, but also during installation. You can track how well the joints are insulated. With its help, accidents are prevented, because the information arrives in advance.

SODK is included in the mandatory program for laying pipelines in PPU insulation in accordance with GOST 30732-2006. The cost of the system is no more than 2% of the total cost of the project, and the benefits from it are enormous. It should be noted that one device with a portable detector is capable of monitoring several objects.

The system includes:

• signal conductors in thermal insulation;
• terminals at the points of control and switching of signal conductors;
• cables for connecting signal conductors to terminals at control points;
• portable and stationary detectors;
• devices for determining the exact location of damage or leakage;
• insulation testers;

The company PSK Polistroy provides services for the design and calculation of UEC systems, the installation of SODK on the highway.

Commissioning of the UEC system at the facility of the operating organization

After installation and debugging, the company's specialists will test all elements of the pipeline. After testing, a survey of the parameters of the UEC system is carried out with the issuance of an act of preliminary delivery. The final delivery of the heating network control system to the operating organization is carried out by the installation organization together with the PSK Polistroy company.

Diagnostics and repair

If a leak appears during the operation of the heating network, it is not difficult to detect it using the UEC system. The insulation of the signal wires gets wet and the signal is weakened or interrupted. A specific place is determined by a device - a reflectometer.

Reflectometers detect breakage of signal conductors, wetting of the insulating layer of polyurethane foam. It is important that the operation of the heating network does not stop during diagnostics. These devices are able to indicate the problem even before the damage detectors are triggered, store the results of previous measurements, and connect to a computer to plot the dynamics.

Specialists of the PSK Polistroy company will not only find the place and cause of the malfunction of the heating network, but also eliminate the pre-emergency situation.

We will be glad to cooperate with you!

The UEC system allows you to monitor the condition of the pipeline, promptly signal a malfunction and accurately indicate the location of any defect. The presence of the UEC system significantly saves cash and reduces the time spent on pipeline maintenance.

The control system allows to detect the following defects:

• Damage to a metal pipe (fistula).
• Damage to the polyethylene sheath.
• Breakage of signal conductors.
• Shorting the signal conductors to a metal pipe.
• Poor connection of signal wires at the joints.

Composition of the UEC system

The operational-remote control system is a special set of instruments and auxiliary equipment (which will be referred to as elements of the UEC system in the future) with the help of which the condition of the pipeline is monitored. The exclusion of any element from the system violates its integrity and normative functionality.

The control system includes the following components:

• Signal conductors
• Control and measuring equipment (damage detectors, pulse reflectometer - locator, control and installation device "Robin KMR 3050 DL").
• Switching terminals.
• Connecting cables.
• Ground and wall carpets.
• Materials and equipment for installation.

Signal conductors

Purpose

All pipelines and fittings (tees, bends, valves, fixed supports, compensators) must be equipped with signal conductors. With the help of signal wires (a signal is transmitted through them - a current or a high-frequency pulse), the state of the pipeline is determined.

Technical specifications

Conductor configuration

The signal wires installed inside the thermal insulation layer of polyurethane foam are pulled parallel to the manufactured pipe and geometrically placed at “3” and “9” or “2” and “10” hours.

Functional purpose of conductors

Mounted wires are exactly the same, however, according to their purpose, they are divided into main and transit wires.
The main wire is a signal conductor that enters all its branches during the installation of the heating main. This wire is the main one for determining the state of the pipeline, as it repeats its contour.
The transit wire is a signal conductor that does not go into any branch of the heating main, but runs along the shortest path between the start and end points of the pipeline and mainly serves to form a signal loop.

Installation of conductors during construction

During the construction of the heating main, the installation of conductors is carried out at the butt joints of the pipeline.
The installation of wires must be carried out in such a way that the main signal wire is on the right in the direction of water supply to the consumer on all pipelines, and all side branches must be included in the break of the main signal wire. Side branches it is forbidden to connect to the transit wire.

Connecting wires at the joints

The signal wires are connected to each other respectively: main to main, and transit to transit.
With the help of pliers, the wires twisted into a spiral are carefully straightened and stretched and, avoiding kinks, are arranged parallel inside.
Wires are stripped with sandpaper from the remnants of foam and paint, and then carefully degreased.
The wires should be stretched and cut off excess parts so that there is no slack when connecting.
Insert the ends of the wires into the crimp sleeve and crimp the sleeve on both sides using crimping pliers.
After that, the resulting connection must be irradiated using an inactive flux, POS-61 solder and a gas soldering iron (or electric, if there is a 220V power supply), the wire connection is heated with a soldering iron, after a few seconds it heats up to the melting temperature of the solder.
The connection is soldered correctly when the solder fills the ferrule on both sides.
To check if the connection is correct, pull the signal wires to check if the splice is OK.
Press the wires into special slots in the wire holders previously attached to the metal pipe.

Description:

A. V. Aushev, General Director of Termoline LLC

S. N. Sinavchian, cand. tech. Sciences, Associate Professor of the Department of RL-6 MSTU. N. E. Bauman

networks central heating and hot water supply are a heat-insulated metal pipe that creates a sealed circuit for moving liquids under pressure up to 1.6 MPa. In the conditions of the city, the task of controlling its tightness is determined both by the need to preserve its functionality, which means reducing heat carrier losses and saving thermal energy, and by the safety requirements of citizens.

One of the methods for monitoring the tightness of a metal pipeline is to control the pressure in it. However, a number of reasons, such as the presence of a coolant flow by the consumer, the dependence of pressure on temperature in a closed volume, and the low accuracy of pressure gauges, make this method very rough.

Detection of leaks in channel and non-channel laying of heat pipelines

Heat pipes can be divided into two groups:

• having an additional hermetic shell of thermal insulation along the entire length (channelless laying),
• with a leaky insulation shell, which mainly performs the functions of its fixation (channel gasket).

Let's consider these groups from the point of view of ensuring the possibility of detecting and localizing the location of a coolant leak.

channel lining are used, as a rule, for pipelines, the insulating layer of which is not protected by an additional waterproofing sheath along the entire length. For channel laying pipelines, leak detection is possible only when using special equipment. Such equipment are acoustic and correlation leak detectors, the principle of which is based on determining the location of a powerful source of sound and vibration vibrations when the liquid flows out of the sealed circuit.

Thermal imagers are also used, the data of which make it possible to determine the location of the maximum level of infrared radiation of the soil, heated by the coolant flowing uncontrollably from the pipeline. Sometimes a chemical analysis of groundwater and wastewater is used, the determination of the presence of a coolant in which indicates a rupture of the pipeline.

However, in urban conditions, the presence of adjacent communications (where the coolant goes), as well as the uneven depth and surface of the soil above the pipeline, make it difficult to determine the location of the leak when using thermal imagers and chemical analysis of water. The search for the location of a pipeline rupture during channel laying, as a rule, consists in an integrated approach when performing these works. In addition, none of the listed methods can be implemented with cheap permanently installed equipment, so there is no economically available possibility of automatic notification of an emergency on the pipeline.

For channelless laying only pipelines are applicable, the heat-insulating layer of which is protected by an additional outer waterproofing sheath. However, this shell not only serves as a barrier to external ground or melt water, but also is an obstacle to the penetration of the coolant into the coating in case of loss of tightness of the metal pipe. In this case, the outflow of the coolant into the sprinkling is not accompanied by a powerful release acoustic noise and vibration, as it happens with channel laying, which is the reason for the low efficiency of the use of acoustic and correlation methods.

The only way (of the above for channel laying pipelines) to determine the presence and location of depressurization of a metal pipeline or outer shell is to use thermal imagers. However, in urban conditions, this method cannot be considered accurate, and automation of emergency notification is not available.

Operational remote control systems for pipelines

The use of an operational remote monitoring system (SOODK) for pipelines in polyurethane foam (PPU) insulation is the only possible guaranteed way to control the state of insulation of a channel laying pipeline. SODK is a complex of an instrument part and a pipe part, consisting of two copper conductors located in the thickness of the insulation parallel to the metal pipeline along its entire length (Fig.). When the insulation becomes wet due to depressurization of the metal pipe and the outer polyethylene sheath, its resistance decreases sharply, which is detected by stationary devices for monitoring the state of the insulation.

According to the data of the detectors, SODK must be recorded at least once every two weeks. The collection of information is traditionally carried out by employees of the maintenance service - "walkers", whose task is not only to bypass many points, but also to record stationary and portable insulation state detectors on paper. The volumes of the introduction of pipelines in polyurethane foam insulation, equipped with SODK, increasing every year, do not allow them to be effectively controlled by bypass, which is the reason for the need to use dispatching systems (see reference).

Dispatch Benefits

Once again, we note that automatic control of the tightness of the metal pipe and the outer shell is implemented only for pipelines in PPU insulation of the channel lining, equipped with SODK. Permanent remote monitoring of the condition of such pipelines has the following advantages over traditional way collection of information:

• Instant notification of a change in the state of the pipeline and the integrity of the SODK.

According to clause 9.2: "For the prompt detection of pipeline damage, it is necessary to ensure regular monitoring of the state of the SODK (at least twice a month) using a detector." During this time, if a metal pipe breaks through, the entire section of the pipeline with polyurethane foam insulation may fail. It is possible for water to spread inside the thermal insulation of the pipeline (between the PPU insulation and the shell, as well as the PPU insulation and the metal pipe) for tens of meters in a short time. Efficient operation of such sections is impossible in the future, the process of their wetting is irreversible, which leads to the need to re-lay tens of meters of the pipeline.

We especially note that the loss of the integrity of a metal pipe in PPU insulation is not accompanied by a sharp drop in pressure in the system, as happens in channel laying pipelines. This is due, firstly, to the tightness of the polyethylene sheath, and secondly, to the channelless method of laying the pipeline in polyurethane foam insulation. The pressure in the pipe can be maintained even when the distribution of network water along the pipeline for tens of meters. This fact indicates the impossibility of detecting an emergency on a pipeline in PPU insulation, except with the help of a serviceable SODK. Within two weeks of not taking readings from the detectors, soil erosion is possible, which will lead to the collapse of the bearing layers of the soil, and this, in turn, in urban conditions can lead not only to great material damage, but also to human casualties.

• Elimination of false calls.

The specifics of the work of "crawlers" determines the possibility of fixing false information by them or the lack of transmission of real information about the readings of the detectors emergency services. Often, when the response teams arrive, the readings of the detectors correspond to normal operation pipeline, and a false call is associated with the incompetence of the "crawler". But it is worse if he did not record or transmit information about the accident on the highway. Employees of the operation service or a third-party organization (working under a contract) responsible for taking readings on site by a bypass method may not actually visit the monitored facilities, while they themselves record the “normal” state of the pipeline, because they know that at this stage no one is there controls. Then the time of soil washing out exceeds two weeks, which significantly exacerbates the consequences of an accident on the pipeline and increases the length of the required replacement. By excluding the human factor from the emergency notification chain, we significantly increase the reliability of pipelines in PU foam insulation.

• Exclusion of the corruption component.

It is possible that an employee of the operation service responsible for taking readings on site, for some reason, deliberately tries to hide or distort the real state of the pipeline - for example, the same employee commissioned a pipeline in inadequate quality or with a faulty SODK. When organizing remote control, it is possible to eliminate the corruption component that occurs during the acceptance of pipelines into operation. Such an approach will also ensure a higher quality of the pipelines to be commissioned, since one employee takes it into operation, and another controls it through the PD.

• Application of multilevel detectors.

As a rule, single-level stationary damage detectors are installed on heating mains. They signal the wetting of the pipeline, in which the resistance of its insulation is reduced to only 5 kOhm. The use of multilevel detectors with a current output makes it possible to detect a pipeline defect at an early stage of its formation. The detection of the insulation resistance of the controlled pipeline occurs in six ranges, the upper of which corresponds to the ideal state of the insulation (more than 1 MΩ). The rate of resistance decrease from the upper range to the lower one (less than 5 kOhm) indicates the size of the defect: the higher the rate, the greater the pipeline defect.

• Ease of perception of the received information, its processing and storage.

Today, all information received from crawlers is stored mainly on paper and is practically not amenable to statistical processing. The data collected by the dispatching system is not only more voluminous, complete and reliable, but also makes it possible to process it using various algorithms of mathematical analysis. This allows you to filter out seasonal changes in the state of the pipeline insulation, false alarms, and errors caused by the human factor. Using a special software allows you to automatically generate reports on the condition of pipelines, track the nature and speed of response of personnel on the ground, and, if a sufficient sample is accumulated, conduct a statistical analysis of information on the use of pipelines with PPU insulation.

• Flexibility of the dispatching system.

The stability and performance of any telemetry system depends on proper organization architecture of interaction of its components. The usual structure of the dispatching system provides for the collection of data from geographically distributed controlled objects (often of the same type) to a single center. There are other options: multi-level construction of control rooms, local nodes for collecting or relaying data, and others, but they do not change the essence of the centralized construction of the system. At the same time, the size of the system, depending on the object, can be either small (in the case of a quarter, enterprise) or gigantic (branch, city, region).

• Economic expediency.

The role of automation and modernization of technological equipment of utility networks in modern reality is not only to improve the quality of public services, but also to reduce the cost of providing heat and hot water transport services. Important economic factors for reducing operating costs are the lack of a payroll fund for linemen, their material support, the lack of the need for training, control and accounting. There are also no additional difficulties associated with organizing the access of "walkers" to the premises where the detectors are installed. Special meaning has a speed of delivery of information about an emergency, which is the main positive economic indicator.

The listed advantages of systems for dispatching the indications of the pipeline state detectors in polyurethane foam insulation became the reason for their use in the early 2000s. The first mention of positive effects was published in. At the moment, in one of the heating networks of the Moscow region, several data transmission systems operate at the same time, exchanging information both via cable lines and via a GSM channel.

Ways to implement data transmission systems

First way- this is the integration of stationary damage detectors as primary sources of information into the architecture of existing telemetry systems that perform the tasks of monitoring and controlling the technological equipment of heat points. The implementation of this method is possible if the SODK detector has a hardware capability to transfer data to the input lines of a remote controller (the detector must be equipped with special outputs for data transfer such as "current output" or "dry contact"). At the same time, employees of heating networks must have high professional skills for successful visualization, analysis and data storage of detectors on the control panel.

Both cable and GSM data transmission channels are used. This method of data transmission is implemented for monitoring and control of a number of heating points in Moscow, Mytishchi, Reutov, St. Petersburg, Astana.

Second way focused on the use of GSM-telemetry systems, which have found application in the electric power industry, gas industry, banking, complexes of security and fire alarm systems. High competition between manufacturers of such complexes is the reason for the emergence of a large number of reliable and cheap GSM controllers, the use of which in order to monitor the state parameters of pipelines in polyurethane foam insulation is a cost-effective and easy-to-implement solution. The main requirements for GSM telemetry systems are the ability to transfer data from the detector to the controller and the availability of dispatcher console software. This software must provide:

• continuous unlimited control over remote objects;
• visualization of the location of controlled objects on the map of the settlement;
• visual and acoustic notification in case of an accident;
• individual configuration of the "Emergency" signal level for each of the objects;
• stability of data transfer when duplicating by various transport (modem connection, SMS, voice connection);
• the ability to transfer and visualize data from security sensors, temperature sensors, pressure sensors, etc.;
• the possibility of automatic polling of objects;
• sending SMS to the phones of responsible persons in case of emergencies;
• personalized management and storage of information about the actions of the operator in the event log;
• friendly interface, smooth operation, easy operation, etc.

Switching of GSM-controllers with detectors, installation and configuration of remote controllers are carried out independently by employees of instrumentation departments or special divisions, which is greatly simplified due to the availability of detailed instructions. The task of forming a local dispatching console (LDP) at the level of a heating network enterprise is easy to do, since it consists in installing and configuring free and intuitive software. This method is implemented by the enterprises of Novosibirsk, Mytishchi, Zheleznodorozhny, Dmitrov.

Third way scheduling of readings of SODK detectors is proposed in. If the operating organization does not see the need to create its own LDP (lack of adequate funding, personnel or a third-party organization of the appropriate level of training, a small number of facilities), it is possible to use the services of a unified dispatcher console (UDP). The ODP, located in Shchelkovo, Moscow Region, receives information from GSM controllers configured to work with the ODP, installed on the territory of the Russian Federation, the Republic of Kazakhstan and the Republic of Belarus.

Emergency notification of the responsible person of the operating organization in the event of an emergency occurs in any way convenient for him (personal account on the EDP website, Email, cellular telephone, dispatch service, etc.). It also provides for a scheduled survey according to a schedule approved by the operating organization.

The operating organization must ensure the safety of the detector and the remote GSM controller at the installation site. installed equipment, its uninterrupted power supply and a satisfactory level of the GSM signal (if necessary, the use of a repeater).

Subsequently, remote transfer of data to a newly created LDP by the operating organization is possible. Thus, the use of RTO services becomes a test option for organizing your own LDP.

The method of scheduling detector readings is determined at the level of design work, since the specification, and hence further funding, is formed by a specialist in the design organization, therefore one of the important tasks of the operating organization is to draw up a complete terms of reference indicating the requirements for the dispatching of the pipeline being designed.

Based on the provided terms of reference, the designer must determine the location and configuration of the control point of the pipeline SODK, equipped with a damage detector. A prerequisite for the continuous operation of such a control point is the presence of 220 V, 50 Hz power in it. Complete sets of control points SODK are also supplied for operation in offline, however, their use is possible only in exceptional cases, since, regardless of the type of power source ( solar panel or batteries) kits for autonomous operation provide only periodic monitoring of the condition of the pipeline insulation, which is the main way to reduce energy consumption.

The experience of implementing and supplying equipment for dispatching the indications of the state detectors of pipelines in polyurethane foam insulation indicates timeliness, a fairly high level of equipment and economic efficiency this direction. Professional approach allows you to fully automate the process of notification of emergency situations on pipelines of heating networks, which is possible only for pipelines equipped with SODK. At the same time, various methods for monitoring the readings of detectors for various levels of professional training of heating network personnel are proposed.

Literature

1. STO 18929664.41.105–2013. The system for remote monitoring of pipelines with thermal insulation made of polyurethane foam in a polyethylene sheath or steel protective coating. Design, installation, acceptance, operation.
2. Kashinskiy V. I., Lipovskikh V. M., Rotmistrov Ya. G. Operational experience of pipelines in polyurethane foam insulation in JSC “Moscow Heat Network Company” // Teploenergetika. 2007. No. 7. S. 28–30.
3. Kazanov Yu. N. Organizational and technical modernization of the heat supply system of the Mytishchi region // News of heat supply. 2009. No. 12. S. 13–26.
4. Thermoline LLC. Album of technical solutions for the design of systems for operational and remote control of pipelines in polyurethane foam insulation. M., 2014.

Thermally insulated expansion joints SKU.PPU are one of the most demanded models of bellows-type compensating devices on the market. Their area practical application covers the areas of pipeline construction by means of channelless underground and open ground laying. Guaranteed high build quality, excellent performance and low prices for SKU.PPU expansion joints manufactured by SanTermo ensured this type of product is in stable demand for companies specializing in the construction of thermal power pipelines.

The LLC PO SanTermo company produces heat-shrinkable couplings of all required sizes. These products fully comply with the requirements of GOST 16338, are certified, and undergo thorough quality control before shipment from the factory. Many thermal power plants and public utilities prefer to use heat-shrinkable sleeves of our production, as they consider them optimal in terms of price-quality ratio. fast and quality seal joints between PPU pipes laid in a trench is important for maintaining high rates of construction of heating mains and ensuring a long period of their trouble-free operation. Thermal couplings from the SanTermo company are made of dense and durable polyethylene, and subject to the installation rules, the tightness of all closed joints guaranteed!

The production of pipes in polyurethane foam insulation is one of the main and priority activities of the SanTermo company. Pipes insulated with polyurethane foam allow to minimize the loss of thermal energy and prevent leakage of liquids transported through pipelines, they are protected from corrosion, they serve for a long time and reliably. We have created our own highly efficient production, and for more than 5 years we have been supplying pipes and fittings in polyurethane foam insulation to construction companies, utilities and wholesale supply organizations in all regions of Russia. The production processes at the plant of OOO PO SanTermo are constantly being improved to ensure even higher quality of all types of pipes and fittings in polyurethane foam insulation, and to minimize their costs. This will allow us to offer even lower prices to numerous partners. All production is certified, passes careful technical quality control.

Tape "TIAL"

One of the most well-known and well-proven in practical work material for anti-corrosion protection and waterproofing of pipes is TIAL heat-shrink tape. LLC PO SanTermo sells almost the entire available range of heat-shrinkable materials from a popular Russian manufacturer of products for sealing joints and protecting pipes from corrosion. The TIAL-M tape consists of two layers, the lower of which, due to its high adhesive properties and thermoplasticity, ensures perfect adhesion to the surface to be protected. Secondly, the outer layer of modified heat-shrinkable polyethylene is extremely durable and resistant to UV radiation. This tape is used for additional sealing and protection of the installation site of heat-shrinkable sleeves at the welded joint of the pipeline. In addition to TIAL-M tape, you can purchase TIAL-3P locking plates and TIAL-3 adhesive tape from us. These materials are also used to provide a better tightness at the pipe connection.

PPU insulation for pipes is the most common and effective material, the use of which can significantly reduce losses in the thermal power industry, significantly reduce construction costs and minimize the operating costs of new heating networks built from PPU pipes. SanTermo specializes in the production of pipes and fittings in polyurethane foam insulation, and can offer customers all the necessary sizes of these products. As a material to protect the insulation layer from damage and excessive moisture, polyethylene (PE) and galvanized sheet steel (OC) are used. The modern production of insulated pipes, created by us, allows us to produce products of the highest quality, competitive in the Russian market both in terms of technical and physical parameters and in price. Our regular customers and partners enjoy maximum discounts and have the right to extraordinary shipment. We accept applications from pipe manufacturers and wholesale supply companies for the manufacture of finished products in polyurethane foam insulation from customer pipes.

The subject of special pride of the staff of the company LLC PO SanTermo is a plant for the production of pipes in polyurethane foam insulation. A modern high-tech enterprise, staffed by well-trained personnel and equipped with all the necessary technological equipment, is able to solve production and engineering problems of any complexity. The geography of deliveries of insulated pipes manufactured by the SanTermo PO plant covers not only the nearest industrial centers, but also many fairly remote cities. The unique thermal and strength characteristics of PU foam insulation are the main factor rapid growth the number of projects that are carried out using PPU pipes. Among our regular customers are construction organizations, utilities and large wholesale companies. Pipes in polyurethane foam insulation have become a sought-after product, and our team is pleased to offer its customers high-quality products at the best price.

Steel pipes in polyurethane foam insulation have numerous advantages. Most of them are due unique properties the main insulator is a gas-filled polyurethane foam polymer. This material seems to have been specially created for the production of thermal insulation of steel pipes. It perfectly adheres to a metal surface, is strong enough, can endure temperatures of +135°C for a long time without loss of strength, and for a short time even 150°C. But its main advantage is a very low coefficient of thermal conductivity. In the volume of PPU components frozen after a chemical reaction, there is no more than 10% -15% of solid matter. The rest is air bubbles, which are the reason for such poor heat conduction. In addition, the very method of applying a layer of PPU insulation on steel pipes is very convenient. It is enough to place the prepared pipe inside the future containment, seal the ends with special plugs, and introduce two liquid reagents into the resulting cavity. After the end of the chemical reaction, the steel pipe will be separated from the shell by a strong layer of polyurethane foam.

When installing heating mains and pipelines from pre-insulated PPU pipes, in places of turning, bending, or connecting additional branches to the main pipeline, it is necessary to install fittings in PPU insulation. It is necessary to use insulated bends, tees and other components in order to ensure the same temperature regime all sections of the pipeline, and the possibility of excessive leakage of thermal energy is completely excluded. All shaped products in polyurethane foam insulation, produced by the plant of the company PO LLC "SanTermo", are distinguished by high quality and reliability. Thermal insulation made of polyurethane foam is reliably protected by an additional shell, which, depending on the needs of the customer, can be made of solid polyethylene or high-quality galvanized steel. The company sells to buyers and customers shaped products in polyurethane foam insulation at the most affordable prices, as it is a direct manufacturer of these products, and is constantly working to reduce production costs.

Since 2009, PO LLC SanTermo has been producing steel pipes in polyurethane foam insulation. During this time, a powerful production base has been created at the enterprise and a team of like-minded professionals has been formed. Today, the company's pre-insulated pipe plant produces everything necessary for laying new pipes, as well as repairing and modernizing existing pipe lines. Steel pipes in polyurethane foam insulation from the company "SanTermo" - a guarantee of standard quality and long service life of the built ones. The company manufactures and sells a full line of products that are necessary for the construction of resource-saving pipelines - steel pipes in polyurethane foam insulation of all required sizes, insulated fittings, polyurethane foam shells and sets of materials for quick insulation of joints. Steel pipes in PPU insulation are offered to all buyers and customers at the lowest, competitive prices that only a manufacturing company can provide. Regular customers and wholesale partners receive additional discounts.

Operational remote control system SODK

Product groups

SODK system

SODK- a set of technical means intended for operational control the integrity of the protective shell of pipes in polyurethane foam insulation, and quick repair work in case of damage. The violation of the tightness of the shell is judged by the change in the dielectric resistance of the polyurethane foam insulation of the pipeline. When it is locally wet, the resistance value between the metal pipe and the copper conductor laid inside the insulation layer changes. SODK.

Purpose, principle of operation and technical implementation of SODK

Ability to create an electronic system SODK, which controls the state of the thermal insulation layer of PPU pipes and the tightness of their outer shell, favorably distinguishes this type of pre-insulated pipes and greatly increases the reliability of industrial pipelines built from them. Designed to continuously monitor the moisture content of the entire volume of PU foam insulation, the system SODK allows you to guaranteedly avoid emergency situations associated with the penetration of water to the surface of working steel pipes, and - as a result, damage to them by corrosion.

In addition, in the event of a violation of the tightness of the outer shell and wetting of polyurethane foam, its thermal conductivity increases sharply, which significantly worsens thermal insulation properties this section of the pipeline. Timely detection of defects in pipe insulation using the hardware complex of the system SODK allows you to quickly produce necessary repairs damaged area, to prevent uncontrolled development of the situation and the significant material damage associated with it.

Operating principle

Operation of hardware control complexes SODK is based on the principle of measuring the resistance of the thermal insulation layer to electric current. Being a dielectric under normal conditions, wet polyurethane foam becomes a conductor - its resistance drops to 1.0-5.0 kOhm, which can be recorded by appropriate devices SODK. To ensure the possibility of making such measurements simultaneously along the entire length of the pipeline, PPU pipes are equipped with special conductors integrated into the polyurethane foam layer at the stage of manufacturing thermal insulation.

Later, during the construction of pipelines, the conductors of all installed pipes are connected into a single circuit. measuring electrical resistance transition "steel pipe - signal wire SODK, the system equipment is able to register any, even the most insignificant, deviation of real parameters from the reference values ​​entered in technical certificate pipeline at the time of commissioning tests. If a SODK registered the presence of insulation wetting, with the help of special remote-action devices - pulse reflectometers, the location of the defect is determined with a high degree of accuracy and repairs are promptly carried out.

The composition of the UEC equipment

The whole complex of technical means SODK It is customary to conditionally divide into three groups - the pipe part, signaling equipment and a group of additional devices. The pipe part includes all passive electrical elements - from conductors embedded in pipes and connecting mounting accessories, to intermediate and end cable outlets. To signal group SODK include the active part of the equipment - measuring instruments, matching devices and switching facilities.

A group of additional devices is formed by securely closing ground and wall metal structures - carpets, in which, during the installation of the system, the equipment of the signal group is installed. Thus, the composition of the equipment SODK includes:

1.Pipe part- conductors mounted in pipes, all mounting and connecting accessories and cable outlets.
2.Signal group- active equipment SODK:
2-1. Control devices: stationary and portable damage detectors.
2-2.Instrumental means of localizing the defect - pulsed reflectometers.
2-3. Equipment installed in control rooms.
2-4. Auxiliary devices - insulation testers, ohmmeters and megohmmeters.
2-5. Switching measuring terminals. There are end, double end and intermediate terminal boxes.
2-6. Sealed terminals are securely closed wiring boxes that protect connections and connected devices from moisture. Distinguish end, uniting and through tight terminals.
3. Additional devices - ground and wall metal carpets.

One of the most costly components of equipment SODK are control devices and technical means troubleshooting. Monitoring devices include stationary and portable detectors, each of which is capable of monitoring sections of pipelines from 2000 to 5000 meters long. domestic producers produce a line of high-quality devices that allow you to completely abandon the purchase of imported equipment - Vector-2000, SD-M2 (Vector Research and Production Enterprise), PIKCON DPS-2A / 2AM / 4A, DPP-A / AM (Termoline LLC). In the group of devices for finding damage, equipment is also widely represented. Russian production- REYS-105/205 (NPP Stell) and RI-10M/20M (ZAO Oersted).

Design rules for control systems

Systems Design SODK is carried out on the basis of the provisions of GOST 30732-2006 and the Code of Rules 41-105-2002. The design organization develops and transfers to the customer a set of documents, including the rationale for the structure and composition SODK, a master plan indicating the places where cable outlets are provided, installation of carpets and switching terminals, diagrams of electrical connections and wiring in the terminals. A separate document contains a list of measuring equipment, control devices and devices for finding faults, recommendations for installation work and subsequent maintenance of the system SODK.

At the design stage, it is important to determine the most optimal distances between the cable outlets and to indicate exactly where the carpets are to be installed. It is recommended to have intermediate control points and corresponding terminals SODK at a distance of no more than 300 meters from each other. At each end of the route, it is necessary to provide for the installation of end cable outlets and terminals designed to connect stationary and portable detectors. All equipment must be located in such a way as to facilitate operation. SODK and ensure maximum accuracy in the production of control and diagnostic measurements.

To the installation of pipe conductor connections, cable outlets and preparation for the placement of ground and wall terminals SODK start immediately after the welding work is completed and hydraulic tests. The procedure for performing installation work, control measurements and transfer of the finished operational dispatch complex to operation should be described in detail in the project. Connection of conductors SODK neighboring pipes is made during the insulating sealing of joints. These, and any other electrical work, are completed by performing control measurements and assessing the quality of each installation connection.

One of the stages of transferring the mounted system SODK to the customer involves the measurement of the resulting ohmic resistance of the mounted signal conductor and the insulation resistance of the "signal wire - working pipe" section. Measurement results are recorded in a special journal and during subsequent operation SODK are used for this pipeline as reference values.

Types of malfunctions and search for places of damage

During operation, the system SODK monitors one of the most important parameters of the pipeline condition - the absence or presence of moisture in the thermal insulation layer, and its own condition - the serviceability of the signal wire. Accordingly, based on the measurement results, the system can fix any of the following faults:

• getting wet a separate section thermal insulation.
• Short circuit when the signal conductor contacts the surface of the working tube.
• Damage (break) of the signal conductor.

The search and localization of the defect site is carried out using portable and stationary detectors, and the most accurate and efficient device - a pulsed reflectometer. Detectors help to determine the area between control points where a malfunction is detected. This section of the circuit is temporarily turned off, and by sending a control high-frequency pulse through the wires, data is obtained on the time of passage of the reflected signal. By comparing the data obtained from each side of the control section, the distance to the accident site is calculated.

SODK system for pipeline control