The use of pipes in composite metal structures is very beneficial: pipes give joints increased strength and rigidity, while reducing the mass of the assembly. However, the pairing of pipes with each other is laborious and requires special preparation of the ends. This work can be facilitated by using special tools - pipe trimmers.
The principle of operation of the trimmer for metal pipes
The task of the pipe trimmer is to minimize the gaps that are inevitably obtained when fitting the ends manually, as well as to give welded joint sufficient aesthetics.
It is known that when connecting and tie-in steel pipes, depending on the angle of their mutual inclination and diameter, the mutual conjugation curve can be a parabola, an arc, or even a straight line. Therefore, it is very difficult to perform a successful pairing by analytical calculation. The problem can be solved by spatial 3D modeling using the well-known KOMPAS or AutoCAD programs, but in practice they do things differently.
In serial production, pipe trimming is carried out using milling machine equipped with a dividing head. The method is accurate, but requires appropriate equipment, which is not always available. home master. At the same time, having a powerful drill for metal (from 1000 W) and a hole cutter, you can quickly profile the end of any pipe.
Industrial Options such devices in the special literature are called tube notcher (slot cutters, although they are also capable of performing curvilinear contours).
The pipe trimmer includes:
- Shaft, at one end of which there is seat for a drill chuck, and on the second - a seat for a hole cutter.
- Bearing assembly, rotating in which, the shaft receives the necessary rigidity.
- Housing, sometimes with a vise for clamping a tubular workpiece.
- Rotary device, with which the workpiece can be positioned at the desired angle.
- Adjusting screw.
With the help of the trimmers under consideration, it is possible to mate pipes with a diameter of 6 ... 75 mm, which in most cases is quite enough. The range of change of mating angles is from 45 to 210 0 . It should be noted that the crown cutter is not included in the device.
For processing long pipes, manual pipe trimmers with a chain clamp are used, and for short products, the supporting and guiding parts of the device are combined in one unit. The safety of work is ensured by the presence of retaining rings, which limit the longitudinal movement of the shaft.
Shaft is the most constructive complex element trimmer. First, it must receive longitudinal movement as the cutter penetrates the pipe metal. Secondly, during milling, vibrations are created, which are caused by a sharp fluctuation in the torque of the base power tool. Therefore, the shaft is made polished, has a sliding fit of high quality accuracy, and the bearings used are needle type, which allow compensation of axial and radial loads.
The price of such devices is from 8000 to 50000 rubles. At the same time, all pipe trimmers of the TT size range are quite compact devices that are fixed in a cartridge lathe. The electric drill is fixed in the same way. When processing pipes of small diameter, the device can rest directly on the floor of the workshop.
Do-it-yourself pipe trimmer
At mass production shaped profiled pipes (for example, in sports car and motorcycle workshops, or in plumbing repair sites), a manual pipe trimmer can also be made independently. For this, the initial scheme of the trimmer, which is shown in the figure, is made under the blanks available to the home master.
The design consists of the following parts:
- Base in which milled grooves are made for installation jig. In turn, the shape of the base can be adapted to the existing workbench, work table, etc.
- L-shaped bracket with three longitudinal grooves, the presence of which allows you to fix the pipe in the fixture different diameter.
- Crawlers with adjusting and clamping screw.
- Replaceable presser foot.
- A bracket that presses the foot to the crawler with screws.
- Bearing unit.
- A pivot arm that serves as a bearing surface for the bearing assembly.
- A shaft that does not structurally differ from a similar part of industrial trimmers.
For the manufacture of the shaft, you can use the front shock absorber strut passenger car(for example, VAZ - they are easier to get at a car service). In addition, the steel grade of the shock absorber strut in terms of its strength and performance characteristics fully complies with the rigidity requirements for high-quality trimming of steel (and, especially, aluminum) pipes. The guides of the rack itself are suitable for guiding the shaft: they have a surface wear-resistant coating based on anti-friction alloys. The ends of the rack, of course, are subject to additional processing - for fastening in a drill chuck, and for installing a hole cutter.
Needle bearings should be pressed into the guides, the size of which is selected according to the dimensions of the guides. Two bearings installed in the guide from the return stroke cylinders of the decommissioned hydraulic press will provide the necessary rigidity and parallelism of the main working unit of the trimmer. Bearings are installed simultaneously from both ends of the housing.
The available advice regarding the installation of fluoroplastic guides should be taken with skepticism, since load bearing capacity PTFE is much lower than bearings.
For the manufacture of other elements of a home-made pipe trimmer, you can use shaped rolled products - corners or channels of the appropriate size. Profiling and making grooves are best done on a jig milling machine, thereby guaranteeing their accuracy and parallelism. It is not difficult to make and clamping device, for which a new clamp with the required diameter and length is suitable.
The swivel lever must have sufficient rigidity, so for its manufacture it is necessary to use a strip with a thickness of at least 12 ... 16 mm. On the part of the body where the swivel arm is installed, it is worth applying angular risks, along which it is easier to position the pipe.
Trimmer for polypropylene pipes
The need to process the end elements of such pipes is due to the following:
- Low durability reinforced polypropylene pipes, especially at significant temperature differences;
- Ensuring a stronger connection of the reinforced pipe with reinforcement parts, for which it is necessary to remove a part aluminum foil;
- For fiberglass pipes, where the aluminum reinforcement is always located in the middle of the pipe wall.
Trimmer for polypropylene pipes with reinforcement includes:
- Two couplings sized to allow stripping of pipe ends of different diameters (typically 16 to 120 mm).
- Replaceable steel knives.
- Pair of rotary handles.
- Aluminium case.
- Nozzle for electric drill (shaver).
A shaver is required for external trimming of pipes. It consists of two parts - a guide, which is made of durable D16T duralumin, and a hard-alloy cutting part. When introduced into the pipe, the latter rests on the guide, after which the drill is turned on (you can also use a puncher) and a part of the reinforcing layer of the pipe is cut out. Since the shaver has a certain length, the facing for different pipes always produced at the same length, which facilitates their subsequent connection.
The price of a trimmer-nozzle for polypropylene pipes depends on the diameter, and is 400 ... 2000 rubles. Trimmers manual type cheaper: from 250 to 800 rubles.
Stripping and reinforcement of polypropylene pipes - not the most challenging tasks, but they have many nuances. This will be discussed in the article.
One of the advantages of polypropylene pipes is their long service life. They can be used many times longer than metal products. But the service life largely depends on the quality of the installation work. It can be increased as much as possible if the reinforced polypropylene pipes were cleaned correctly.
It plays such a high role due to the fact that the presence of various bumps and burrs will prevent a reliable connection. Even during installation planning polypropylene pipeline it is worth delving into why this procedure is required. It is also worth figuring out what tools exist for stripping polypropylene pipes (read: ""). Special attention should be paid to products with a reinforcing layer.
Features of the reinforcement of polypropylene pipes
High operational properties polypropylene pipes are achieved due to their coating protective layer. When it comes to products intended for domestic use, then usually its thickness is not more than 0.1 mm.
Advantages reinforced pipes:
- Reducing the impact of high temperatures on the product. An ordinary polypropylene pipe is designed for operation in conditions where the temperature does not exceed 95 degrees. This is usually sufficient for the installation of heating systems or domestic plumbing. However, in certain situations, such as emergency situations, the temperature of the transported liquid may exceed the maximum permissible value. This mode of operation leads to the fact that sections of the pipeline are deformed or completely fail. Reinforcement reduces the impact of high temperatures on the product, preventing system breaks.
- Increased resistance to temperature changes. One of the main disadvantages of conventional polypropylene pipes is their susceptibility to temperature changes. The result is their sharp expansion and contraction. The product does not tolerate such deformations, gradually losing its original properties. Over time, the pipes will simply fail. To avoid this situation, they are additionally reinforced.
However, reinforcement has one significant drawback. It makes welding a bit more difficult. polypropylene compounds. For this reason, pipe cleaning is required beforehand. The procedure is extremely simple: removing the top thin layer of aluminum from the product. If this is not done, the quality of welding will decrease, which will lead to a decrease in the service life of the entire pipeline.
It is important to work carefully, understanding general principle. For a better understanding, check out technological process and also prepare necessary tools. detailed information These issues will be discussed later in the article.
Stripping polypropylene pipes
There are several stripping methods, each of them is designed for a specific reinforcing layer.
outer layer. If reinforcement is applied as the top layer of a polypropylene pipe, then it will become an obstacle when connecting the structure to the fitting. Then the pipe section included in it melts during installation. If you miss the stripping, then the molten aluminum will not be able to bond with the molten polymer. In this case, nothing will ensure the tightness of the connection. It will break immediately after the system is started.
The inner layer. Despite the fact that aluminum located between the polypropylene layers is not used for welding, it still needs high-quality cleaning. It is necessary in order to prevent the interaction of aluminum and water. If a potential jump occurs in the pipeline, then there is a risk of electrochemical processes. They can completely destroy the aluminum layer.
Clue! It is possible to apply a reinforcing layer of aluminum in one piece or with holes. If there is a choice, then the second option is much more preferable. The perforated aluminum layer has good adhesion and does not require glue. In addition, stripping a pipe with perforated aluminum is much faster.
fiberglass reinforcement. In this embodiment, do-it-yourself stripping for polypropylene pipes is not required. Between the layers of polypropylene is placed a thin wall of fiberglass. It does not come into contact with the fitting, nor is it exposed to liquid. One of the advantages of this method is that secure fastening pipes is achieved without additional work. But one drawback follows from this - sudden temperature changes have a greater effect on such products than on options with aluminum reinforcement.
Stripping tools
There are manual and mechanical stripping tools for polypropylene pipes. Hand tools great for doing work at home. If there is a more voluminous task, then mechanical tools will already be required.
Types of cleaning tools:
- Stripping for the outer layer. To remove the outer layer of aluminum, special couplings are used, in the middle of which blades are placed. In such devices there are handles (removable and non-removable), which greatly simplify the workflow.
- Trimmers. In such a tool, the blades are located on the inner end of the coupling, and not on the outside. The trimmer is threaded into the pipe, then it is necessary to do several full turns. This allows you to get the perfect cut. Then you can proceed to welding products. Such pipe stripping tools are also used for other types, not only polypropylene ones. Even those without a reinforcing layer are suitable.
- Shaver. This is a special drill attachment used to clean both the inner and outer layers of the pipe. There are shavers designed for different types reinforcement. They vary in diameter.
Important nuance! It is worth understanding the difference between cleaning pipes before welding with cleaning metal products. It's two different types work. Each of them uses different equipment. In addition, they have different technological processes, which should also be taken into account.
Also for cleaning polymer pipes you will need: a tape measure, the necessary cleaning tool, a construction pencil for marking, a soldering iron, as well as scissors, a pipe cutter or a hacksaw. These are popular tools, they can be found in almost every home.
To obtain a perfect pipe cut, high alloy steel tools should be used. Bilateral solutions are preferred. Such a tool is effective when working with products of different diameters.
Stripping for polypropylene pipes is not particularly difficult. One person can cope with the task, special knowledge is not needed for this. It also does not require expensive tools. Simple machines will do just fine. Even with their help, cleaning can be done quite efficiently and accurately. It is enough just to prepare everything in advance, having carefully studied the technological process of this task.
Quite often, ridiculous situations happen to people. For example, when starting to repair the pipeline in the house, the owner calls the installers. Of course, specialists take a certain amount of money for their work. The final price is formed from the amount of materials spent, as well as the actions that they performed. Starting to understand, the customer does not always understand what kind of actions and why they were committed by specialists, as a result starting a dispute.
Undoubtedly, in this situation, the customer looks ridiculous, because, without understanding, he disputes the final cost. In order to avoid such a situation, especially regarding the replacement of old pipes with new, polypropylene ones, you should independently figure out what a trimmer for polypropylene pipes is and why it is needed.
Undoubtedly, they are the most popular today, as they are endowed with a number of advantages. However, in addition to a large number of advantages, polypropylene also has a number of features that should be considered when choosing this material. Don't forget two very important factors when choosing these pipes:
- the maximum temperature of the liquid should not exceed 95 degrees. Based on the current standards, such pipes can be used for laying hot water supply, since the water temperature, according to them, is limited to this particular mark. However, unforeseen circumstances also happen, but rarely;
- thermal expansion has a high coefficient. The flexibility of the material is able to compensate for this factor, however, in certain cases, the deformation of the pipe can adversely affect. An example is hidden pipes under plaster.
Reinforcement solves both problems to some extent. Of course, the reinforcement copes well with thermal expansion, in addition, it also prevents the plastic from softening and deforming during high temperature heating. However correct installation piping out requires some knowledge, including how to use a trimmer.
To date, there are two options for reinforcing a polypropylene pipe:
- using aluminum foil. In this case, the aluminum layer varies between 0.1 mm and 0.5 mm. This layer can be located both outside the product and inside it. Connected aluminum with plastic by means of glue;
- with fiberglass mesh. The design of such pipes consists of three layers - polypropylene, a mixture of fiberglass and polypropylene, polypropylene.
Not many people know, especially when taking on an independent change and installation of a pipeline, that it is imperative to strip the reinforcement before installation. But this is very important!
What is it for?
The need for stripping
It is a simple process consisting of several stages. Each stage involves the use of a special tool, without which stripping cannot be done. One such tool is a polypropylene pipe trimmer. It should be noted that with fiberglass reinforcement, stripping is not required, since the mesh is securely hidden between polypropylene layers, which saves it from contact with water.
In the case of external or internal aluminum reinforcement, stripping is required in without fail. So, in the first version, the foil covers upper surface pipes. Installation of the pipeline involves the connection of its individual elements by means of a fitting or gluing. AT this case slight melting of both pipe surfaces is required. Of course, the polypropylene alloy will in some way weld with aluminum, which will negatively affect the reliability of the structure, and it will crumble over time. This can be easily avoided by stripping the foil.
The second option, when the foil is conveniently located inside the pipe, involves trimming polypropylene pipes, since aluminum will be in direct contact with water. If we omit the facing procedure, then the slightest potential difference will lead to the destruction of the structure as a result of electrochemical processes.
Tools
The easiest way to remove the foil is for external reinforcement. Simple tools will help in this matter - couplings with steel blades inside. They are easy to use, you just need to insert the pipe into the coupling cavity and turn, the blades will do their job quickly and clearly. It is very convenient to use double-sided couplings, with which it is easy to produce having a different diameter from each other.
Internal cleaning is carried out by means of a trimmer. Externally, the design of the trimmer is practically no different from the design of the couplings. So, this tool is a clutch, the blades of which are located on the side of the inner end of the device. As in the first option, it is necessary to insert the pipe into the cavity of the device and make several turns.
A universal tool with which you can remove reinforcement, both internal and external, is a drill with special nozzles. Outwardly, they differ from the same facer in the presence of a steel rod, which is necessary for installation in a drill socket.
Trimmer - what is it?
Above, a few words were mentioned about the trimmer and why pipes need to be trimmed. It is worth taking a closer look at this tool and understanding its device. Quite often you can hear another name for the trimmer - a stripping tool for stripping the middle layer. This name is fully justified by the specialization of the tool, with which it is easy to clean internal reinforcement pipes.
The trimmer device for polypropylene pipes allows in no time to clean the pipe from the foil to the depth required to connect it to the fitting. Inside the tool are steel knives, which, when the tool is turned, carefully cut the foil to the required level.
It should be noted that modern trimmers are equipped with a system of adjustable knives. Thanks to this, it became possible to purchase a one-time tool that is suitable for working with pipes. different manufacturers. With the help of the regulator, you can quickly adjust the knives to any level of foil placement. In addition, there are trimmers on sale, on both sides of which there are cavities designed for pipes of various diameters. This approach also allows you to avoid spending money on the purchase of an additional tool.
When carrying out permanent cleaning work, it is recommended to purchase a nozzle for a drill in the form of a trimmer. In this case, a person will not need to clean the pipe manually. The drill allows you to process a large number of pipes in a short period of time without the use of physical force.
It is worth saying that automatic cleaning is advisable only for large and regular volumes of work. One-time trimming should be done manually. It is important to remember that polypropylene - soft material, and the slightest deviation will damage the pipe. Manual trimming is incapable of harming the product.
Dimensions and cost
Today, a large number of varieties of tools can be found on sale, and the trimmer is no exception. The cost of this tool varies from 300 rubles to 1000. Of course, you can find goods for more high price. When choosing a tool, you must carefully examine its condition. There should be no damage or burrs. Any flaw may damage the pipe when it is placed in the trimmer, or the pipe may not enter it at all. No less attention should be paid to the condition of the blades. It is important that they are made of steel, the softer material may be damaged by contact with aluminum or fail to cut through it.
You can also find replacement blades for the tool on sale. Of course, over time and with frequent use, they can become unusable. Replacing blades is much easier than buying new tool. The most popular today are facers designed for pipes of the following sizes:
- 20/25 mm;
- 32/40 mm;
- 50/63 mm.
The cost of a product depends on its size. So, a trimmer for small pipes will cost much less than an analogue designed for pipes with dimensions of 50/63 mm.
Market building materials offers big choice pipes made of polymeric materials.
Advances in organic synthesis have made it possible to create materials that show excellent performance characteristics.
Polypropylene products are popular - every second apartment or a private house have plumbing or heating from such pipes.
Technical description
Modern technologies have made it possible to create a durable, lightweight material, which is not subject to corrosion, has good strength characteristics, does not react with aggressive media.
small price, low weight, ease of installation determine the widespread use of polypropylene pipes (what is it).
The industry produces several types of products, some of which contain a reinforcing layer outside or inside the pipe.
Quality soldering such models is possible only in the case of stripping the ends of aluminum foil.
We use two types of shaver:
- manual,
- automatic.
The first ones are used when performing one-time operations, the second one is able to clean pipes in large volumes, which is typical for large construction companies ().
The need for reinforcement
Plumbing or heating system made of polypropylene, in addition to the advantages, has several significant disadvantages.
Despite the ability to transfer water with a temperature of 90-95 degrees and withstand short-term heating up to 100 degrees, the polymer has a high coefficient of thermal expansion (about the technology of mounting metal plastic pipes read the article).
Flexible Structure will allow the product to restore its shape when the temperature drops.
But such a situation can become critical when the pipeline is hidden in the walls or under the floor.
Adding a layer of fiberglass or aluminum foil to the composition of the product will reduce thermal expansion and avoid deformation when heated.
Reinforcement helps in the linear sections of the pipeline, but there is no foil in the compounds. This leads to softening of the polymer at temperatures above 100 degrees.
In such places, a breakthrough of communications is possible, therefore the use of reinforced products is not recommended for industrial pipelines.
Used to reinforce pipes.:
- fiberglass.
Structurally, the pipe consists of two layers of polypropylene and a middle layer of a combination of fiberglass and polymer.
Such products do not need to clean the ends before welding; - aluminum foil.
Popular type of reinforcement.
Manufacturers produce pipes with different thickness foil.
The most common are polypropylene pipes, fiberglass reinforced() with a layer thickness of 0.1-0.5 millimeters.
The metal layer can be located inside the product or cover the pipe from the outside.
Why do you need to clean the ends
In the process of stripping the reinforced product, the metal layer is removed at the place of the future connection with the coupling or fitting.
The need for external stripping occurs when using reinforced pipes with an outer layer of foil. Without removing the reinforcement, it is impossible to solder the pipes.
used to remove metal from a surface special tool(which is needed for the installation of pipes made of cross-linked polyethylene, it is written), with which the product is cleaned to the depth necessary for welding.
Drill bits made for one pipe diameter.
To work with such a tool, it is necessary to prepare the necessary nozzles in advance.
Using a drill will increase the stripping speed, the number of processed pipes and labor productivity.
The nozzle is able to work both with external reinforcement and with internal.
How to choose
Product is selected, according to the type of pipes, and is clamped into the chuck. The disadvantage lies in the high speed of rotation - it is necessary, constantly, to control the process. Otherwise, the pipe may be damaged.
If you want to know how to perfectly clean the end of a pipe before welding, watch the video.
