Welding of low pressure polyethylene pipes. Welding of polypropylene pipes, we work with our own hands
The modern market of sanitary products pleases consumers with the opportunity to choose the most suitable option, but at the same time requires knowledge about the properties of materials and methods of their installation. The quality of the pipeline largely depends on the quality of the connection of individual elements, the most reliable, durable, hermetic of which is soldering.
Soldering copper pipes is not easy, you will need a special toolCopper pipe soldering
Copper is an expensive metal, but a pipeline made of it has competitive advantages allowing copper systems to stay at peak demand. Properly made of copper will ensure a long and trouble-free service life plumbing throughout the life of the house, exceeding half a century. The practicality of processing such products lies in the simplicity of the soldering process - it is low-temperature, easy to carry out in living conditions in the presence of gas burner or electric soldering iron.
Set of tools
The complete set of tools, fixtures and materials used in the process for the soldering procedure is as follows:
- tools for expanding, cutting and stripping pipes: expander, pipe cutter or grinder with the thinnest disk, beveler, sandpaper, metal brush;
- a tool for heating metal and melting solder: a gas burner or an electric soldering iron for 250 W;
- materials with which the connection takes place: flux and solder from an alloy of tin with copper, antimony, silver or other additives;
- auxiliary materials - napkins for removing excess flux, stands, gloves, measuring and marking tools.
Copper tubes will be connected without fittings - the edge of one is expanded with a pipe expander, another piece is inserted into it. The connection is heated, and the seam is poured with molten tin solder - a reliable hermetic joint is obtained that can withstand quite a lot of pressure and high temperatures. You can correctly solder copper pipes by understanding the principles of the ongoing process:
- after cutting the tubes, before soldering them, the ends are carefully cleaned - all burrs are removed, and the edge is polished to a bright yellow color. This must be done to remove oxides from copper that prevent soldering;
- after stripping, it is covered with a special composition - flux, which removes oxygen, preventing oxidation during welding, helps the molten solder penetrate deep into the joint;
- flux-coated segments are put on one another and heated with a torch or soldering iron. The technology of soldering with a soldering iron in this case differs from working with a burner only in the absence of an open flame;
- solder is brought to the heated surface under the flame - the tin is melted, drawn into the joint, spreading evenly around the circle of the joint;
- after cooling, the excess tin will fall off by itself, and the seam will be hermetically sealed.
Advice. In everyday life, it becomes necessary to connect aluminum tubes, which are more difficult to process than copper. This will require aluminum solder and aluminum soldering equipment - a torch capable of heating the metal to 400 ° C. The specificity of the procedure is that the flux is not used, and the solder is not injected into the flame, but is applied to the joint: it melts from contact with hot metal.
Soldering pipes made of polypropylene PVC (plastic)
Polymer products are soldered at more than low temperatures than metal. They are afraid of an open flame, so special electric soldering irons called welding machines are used for welding.
Welding technology for products made of polypropylene (PP) is fundamentally different from working with copper. The connection of metal sections is the insertion of one segment into another, and then the sealing of the seam with the help of a weld from a softer metal. In the case of polypropylene, both segments melt, mix, completely penetrate one into the other, and when solidified, an inseparable homogeneous connection occurs. Such welding is called diffuse from the Latin word diffuse, meaning mixing. Soldering propylene pipes means doing three things:
- melt the ends of the segments to a soft state;
- connect one to the other without unnecessary turns;
- wait for cooling - as a result, a homogeneous inseparable area is formed.
Soldering pipes for heating and plumbing at home
Due to the simplicity of the do-it-yourself procedure, it is carried out at home. To do this, you need to purchase:
- electric welding machine for welding polypropylene;
- attachments for the device (included with the device);
- trimmer;
- fitting;
- accessories: marker, knife, tape measure.
Soldering propylene pipes do-it-yourself consists in sequentially performing the following operations:
- Cut pipes to predetermined dimensions, prepare fittings if necessary.
- Trim the ends - remove 1–1.5 mm of the protective layer from above. This can be done with a trimmer or by sanding with sandpaper.
- Prepare the welding machine - equip it with nozzles according to the diameter of the pipes and plug it into the network. Polypropylene melts at 250°C. The device has a temperature relay and a heating indicator. When the desired temperature is reached, the device gives a sound or light signal that it is ready for the welding process.
- Insert the pipe and fitting into the appropriate nozzles and hold the time strictly according to the instructions, avoiding either overheating or underheating.
- Remove the heated parts from the nozzles, then solder by inserting one element into another. At this stage, the actions must be confident and clear - it is forbidden to move the elements back and forth or rotate along the axis.
- Let the polypropylene cool down - leave the structure for a while without mechanical influences.
- Check the connection visually for defects: if the technology is followed, the seam will turn out to be uniform and durable.
Proper soldering of large HDPE pipes at normal temperature
They are of two types:
- low-strength - made under high pressure and acquire a low density;
- high-strength (HDPE) - are made under low pressure, but acquire a high density.
Another name for high strength polyethylene pipes HDPE stands for low pressure polyethylene. The words "low pressure" in the name mean the conditions under which the products were manufactured and are not related to the scope. Low pressure polyethylene (HDPE) is used in conditions high pressure and temperatures - in the main gas or water pipelines. Correctly soldering polypropylene pipes is not an easy task.
Since HDPE products are produced in a wide variety of diameters (20 mm to 1 m 20 cm) and wall thicknesses, there is more than one method of their connection and many types of equipment for soldering polyethylene pipes. Welding of polyethylene pipes is carried out by one of the following methods:
- butt (or butt);
- socket;
- electrofusion.
PE pipe butt welding industrial environment is produced by an expensive and bulky unit with a mechanical or hydraulic drive. The set of the device includes guides for centering, a trimmer for even trimming of joined edges, a heating element, drives and timers. The butt technology itself is simple, but the equipment used is not cheap: the price of a welding machine for HDPE pipes averages 250 thousand rubles, and a separate heating element costs about 50 thousand.
The scheme of soldering polyethylene pipes with a soldering iron in hard-to-reach places
Soldering of polyethylene pipes occurs according to the following scheme:
- the products to be joined are inserted into the machine for welding HDPE pipes, centered;
- an automatic trimmer is inserted between them, which evenly cuts the HDPE, removing chips;
- opposite ends are joined, visual control of the alignment and tightness of the edges is carried out;
- the ends to be welded are degreased, a heating element is installed between them;
- there is heating and melting of the ends at a given temperature for a certain time;
- the heating element is removed and the connection cools down for the period set by the timer;
- a strong connection is obtained that does not affect the flexibility of the pipeline.
At home, it happens according to the same principle, but simpler devices are used - a soldering iron for polyethylene pipes. It costs from 30 thousand rubles, it is a Teflon-coated welding mirror and can withstand high temperatures - up to 300 ° C.
Butt welding parameters for polyethylene pipes: temperature, heating and cooling time - depend on the diameter and wall thickness, they are set by welders according to a special table. To eliminate errors in many devices, the settings are automatically configured.
Electrofusion welding of HDPE pipes belongs to the industrial category and consists in melting the section of the pipeline under the coupling, to which electric current is supplied, and the temperature rises. Electric couplings for polyethylene pipes consume a large amount of electricity during operation and are considered more expensive, but they help out in cases where it is impossible to use a device with large dimensions. They can be used at home.
Soldering reinforced PVC pipes
You can solder using the same apparatus that is used for welding polypropylene counterparts. The walls of PVC products are thicker and more rigid, so fittings are required to connect them. Their melting point is lower, so this type is not used for hot water supply - the walls of the pipeline are deformed under the action of high temperatures. Soldering is carried out by an electric welding machine with nozzles on which the ends of the products to be joined are melted. To properly solder pvc pipes, you need to perform several actions:
- clean the edges;
- reinforcement, if any, removed;
- set the melting point to no more than 200°C.
Tools, fixtures, sequence of actions are the same as when working with polypropylene samples.
WATCH VIDEO
Polypropylene, polyethylene or PVC pipes in everyday life are often referred to as one common word plastic, and the principles of their connection have much in common. Not everyone knows how to solder pipes correctly, but everyone can learn.
Today, products made of polymeric materials are used in many spheres of our life and industries. But HDPE is especially popular - low-pressure polyethylene. This material differs in durability, durability, thanks to small specific weight it is easily mounted. Pipelines for various purposes are often made from polyethylene pipes. To connect individual workpieces, HDPE products are welded. In our article we will talk about the varieties and features of welding HDPE pipes.
Connection types
To connect polyethylene pipes, you can use the following methods:
- Detachable. To perform such a docking of HDPE blanks, you will need steel flanges. The main feature of this docking principle is that the pipeline can be disassembled during operation.
- One-piece. In this case, disassembly of communications will not work. To make such a connection, the workpieces must be welded. This can be done using one of the following methods:
- butt welding of polyethylene blanks;
- welding of products from HDPE by means of couplings.
For the assembly of pipelines from elements of large diameter, thermoresistive fittings or butt welding are used. When using both methods, a reliable monolithic connection is obtained.
Butt welding of HDPE products
Butt welding of HDPE pipes requires the use of welding equipment. Due to the fact that no additional parts are used during welding, the installation process is greatly simplified. In this way, only HDPE blanks can be welded.
Attention: high-quality butt welding of HDPE products will be obtained only on the condition that it is performed with a single seam. Due to this, the strength of the joining of the parts to be joined will be maximum.
Butt welding of polyethylene pipes is the most efficient and versatile technology, since it maintains the flexibility of the material throughout the entire pipeline. This method can be applied regardless of the type of pipeline installation used (trench, trenchless or open).
Butt-soldering of polyethylene pipes is performed in the following sequence:
- To begin with, the ends of the workpieces to be joined must be installed in the centralizer of the welding equipment.
- After the parts are aligned and fixed, with the help of a cotton napkin and alcohol, it is necessary to clean the ends of dust, dirt and grease.
- Then the ends to be welded are processed using a facing device. Trimming is stopped when uniform chips with a thickness of not more than 0.5 mm begin to form. Now the workpiece can be removed and the parallelism of the ends can be checked by hand.
- If an unacceptable gap is found between the surfaces to be welded, the trimming operation must be repeated.
- After that, the pipes are soldered. To do this, using a heating element with a non-stick coating, the ends of the workpieces are heated to the required temperature.
- When the ends are sufficiently melted, we separate the products to be welded, and also remove the heating element from the welding zone.
- After that, the ends to be welded can be closed and the clamping pressure can be increased until it reaches the required value.
- The weld must be kept under pressure for the specified period of time.
- After that, the quality of welding is checked. For this, they evaluate appearance grate, width and height.
Socket welding of HDPE blanks
Welding of HDPE pipes by the coupling method is carried out using a special welding unit called a soldering iron, as well as a set of special nozzles that may differ in diameter. The size of the nozzle is selected based on the diameter of the polyethylene pipes to be welded.
Coupling soldering of HDPE pipelines is carried out using fittings. The configuration of these products may vary. They come in the form of corners, tees or couplings. With this method of soldering, the ends of the workpieces and fittings are welded.
Important: the main advantage of socket welding is that it can be carried out in hard-to-reach places where axial displacement of workpieces is difficult.
Heating of polyethylene parts is carried out by contacting the workpiece with a heated metal part of the welding unit. It consists of two twisted parts:
- mandrel heats the inner surface of the fitting;
- the heating pipe is inserted into the sleeve.
To install this nozzle in the hole of the soldering unit, the sleeve and mandrel must be twisted together.
Soldering polyethylene pipes by the coupling method involves the following preparatory measures:
- The blanks must be cut with special scissors to the desired size. In this case, it is necessary to ensure that the cut is strictly perpendicular to the longitudinal axis of the product.
- Before soldering, the ends of the workpieces to be joined must be cleaned.
- To prevent unwanted cooling during welding, the ends of the pipes that are not currently being joined are closed with plugs.
- After that, it is necessary to clean the surface of the nozzle for welding from particles of material that could remain after the previous work.
Now you can proceed to the welding process itself, which is performed in the following sequence:
- First, the nozzle must be heated to welding temperature. When the value reaches the required level, the indicator on the body of the soldering iron will give a signal.
- After that, the HDPE pipe must be inserted into the sleeve until it stops. In turn, the fitting is put on the mandrel as far as it will go. Since the diameters are slightly different, some effort will have to be applied to complete the procedure.
- We select the time for welding pipes according to special tables, where this indicator is indicated for products of different diameters.
- In the process of inserting the tubular element and putting on the fitting, the excess material from the surface of the blanks is melted and squeezed out. As a result, an annular bead is formed along the edge of the welded elements - a hart.
- Pressing when inserting parts should be stopped at the moment when the workpiece and fitting reach the stop. It is very important to observe this condition, because otherwise the connection will not be strong enough. Since it is difficult to accurately determine the depth of immersion of the workpiece, it is necessary to first measure this value and put a mark on the pipe.
- Then remove the pieces to be welded from the nozzle. After that, install the pipe into the fitting in such a way that it rests firmly against the annular bead. Let the connected elements cool down. At the same time, they should not be twisted and subjected to various mechanical influences.
Electrofusion welding
To make such a connection, a special electrical coupling is needed, into which embedded heating elements are mounted. If we compare this welding with butt welding, then it will cost more due to the need to purchase expensive electric couplings.
However, this technique has its advantages:
- Since no burr is formed on the inner surface of the pipes, the permeability of the pipeline does not decrease.
- This method of welding is convenient to use in a limited space, where it will not be possible to install an overall welded unit.
To connect two blanks into a straight section of the pipeline, conventional electric couplings are used. However, in some cases electrofusion tees and saddles may be required. To perform the work, you will need an electrofusion unit for welding.
The welding procedure is performed using a polyethylene welding fitting. This is a special product that has built-in spirals that act as heating elements. At the same time, a part of the fitting material, which is melted due to the heated spiral, is connected to the polymer material of the workpiece, forming a continuous monolithic pipeline. By the way, the spiral remains in the resulting seam forever.
Important: electrofusion technology allows you to get a connection of high strength. However, due to the high cost of this method, it is used in the installation of pressure lines for the transportation of gas and oil products.
Electrofusion welding is performed in the following sequence:
- With the help of special cutting equipment, the pipes are cut into segments of the desired size.
- Next, the blanks must be cleaned of dirt and degreased at the welding site. The electrical coupling must be subjected to the same treatment.
- Then, marks are made on the tubular elements, which will allow you to control the depth of insertion of the pipe into the coupling.
- To prevent unwanted cooling of the elements during welding, the free ends of the pipes are plugged.
- With the help of special wires, the welding unit is connected to the electric coupling, the start button is pressed.
- After a certain period of time, the unit will turn itself off, which will mean the end of welding.
- The connections obtained in this way can only be operated after one hour.
Attention: the main condition for obtaining a high-quality seam is the immobility of the parts during the welding and cooling process.
The following requirements are imposed on the obtained welded joints:
- The annular weld bead should overlap the mark made on the workpiece before welding.
- The allowable displacement of pipe segments relative to each other is no more than 10% of the wall thickness of the HDPE element.
- If the wall thickness of the workpiece to be welded is no more than 5 mm, then the height of the bead at a high-quality weld should be approximately 2.5 mm. In the case of welding pipes with a wall thickness in the range of 6-20 mm, the height of the bead should be more than 5 mm.
When choosing a method for welding blanks from HDPE, it is worth considering the operating conditions of the installed utilities. Only with this factor in mind, it is possible to make a reliable and high-quality pipeline that will work effectively for the entire period allotted to it.
Welding HDPE pipes is a very simple process. It is carried out using specialized devices, they have different kind– depending on its type. The connection of HDPE pipes can be done in two ways:
- butt-to-butt heating element with non-stick coating;
- with an electrofusion coupler.
Each method has both its advantages and disadvantages.
Soldering HDPE in both ways can easily be done by hand. Connect in both cases should be butt to butt. This will achieve the appearance of the highest quality seam that can easily withstand the pressure declared by the manufacturer.
Heating element connection
The device that performs HDPE welding, using end melting, is rather cumbersome. The reason for this is not only the equipment itself, but also the centering element. After all, one of the most important do-it-yourself welding processes is the alignment of the ends. Since the quality of HDPE welding itself directly depends on this. The process itself is carried out in the following sequence:
- special centering equipment securely fixes the ends for welding;
- it follows with your hands, as carefully as possible, to remove a certain amount of material from the ends of the HDPE pipe;
- after chamfering with a special device, it is removed;
- checked by hand mutual arrangement ends, they should be directly opposite each other.
When all preparatory work completed, you can proceed directly to pipe welding. It is necessary to use the welding machine as carefully as possible, because they can easily get burned. Heating muffs also require careful handling. When the ends of the pipes have melted and become liquid, you can combine them. After that, the soldering should cool down for some time, after which it is checked.
Electrofusion welding
Soldering with a special coupling with embedded heating elements is a simpler and more convenient process. Its main advantage is that the welding machine is very compact. It is easy enough to use even in places where the amount of free space is extremely limited. In this case, special fittings are often used to fix a new seam, if large-diameter engineering communications are being laid.
Soldering HDPE pipes with your own hands is quite simple. It includes several stages:
- pipe end surface preparation ( clean off dirt and grease);
- the coupling, with the help of auxiliary tools, is put on the ends (special reinforcement allows you to fix them as rigidly as possible);
- after a certain amount of time, the clutch is removed.
When the seam has become strong enough, the fixing reinforcement is simply removed.
The main nuances of welding
When carrying out the installation process of polyethylene, many questions arise. In order to connect HDPE pipes correctly, it is very important to always remember some of the nuances:
- when soldering is carried out on its own (auxiliary fittings are not used), it is important to correctly center the connected ends- for this you can use a hard and even surface (concrete, asphalt);
- if special reinforcement is used, it is necessary to be as careful as possible, since pulling the material can damage it;
- using connectors, it is important to keep track of time and temperature, since overheating of the material can prevent the production of a high-quality seam;
- the connection of HDPE pipes must be carried out in compliance with safety regulations - the welding machine can severely burn your hands;
- before using the welding machine, it is advisable to clean it in a cold state with a special cloth;
- when soldering on your own, you must remember that you need to plug the holes at the ends with rags or special plugs, since the welding equipment can cool down under the influence of a strong draft (heating couplings are especially susceptible to this);
- before each new use, the equipment must be checked, a test should be taken - this will avoid damage to the material.
Many are interested in how to connect HDPE pipes in such a way as to achieve the highest quality seam. It is very simple to do this, you just need to use high-quality equipment and take into account all the possible nuances that arise in the process of work. It is also important to remember about the technology for implementing the process in question. The resulting connection must meet all the necessary standards.
Times change, technology changes too
For many years, the most common material used for organizing water supply and heating systems was steel products. However, such negative qualities as low corrosion resistance, ability to overgrowth, high cost and complexity of installation, led to the need to find alternative materials for the manufacture of pipes. The creation of polymers opened a new era in pipe production. In addition, welding polypropylene pipes do-it-yourself is possible without special professional skills and bulky equipment. However, you should follow certain rules for PVC pipes, but more on that later.
Self-welding of polypropylene products
However, before going to a building supermarket or to the market, it is worthwhile to figure out what options a wide range of plastic pipes offers us today? To begin with, it is worth saying that all pipes made of polymers are called “plastic”, and they are divided as follows: products made of polyvinyl chloride (PVC), polypropylene, polyethylene, including cross-linked, metal-plastic.
Scopes of polypropylene materials, methods of their connection
Universal Solutions
One of the most popular and widespread are polypropylene pipes. They can be used for: cold and hot water supply, organization heating system, including "warm floor", sewerage, sewage disposal.
For cold water supply
For filing cold water you can use fairly cheap products labeled PN 16, which characterizes the value of the working pressure - 1.6 MPa. For hot water supply and heating - PN 20 with a nominal pressure of 2 MPa.
If you want to purchase products of a more modern range, then you can opt for structures reinforced with aluminum foil (do not confuse with metal-plastic ones!). A feature of working with such products is the need for their end cleaning before soldering. This procedure can be carried out either using special nozzles for a perforator, or using a manual shaver designed for four main sizes - 20, 25, 32, 40 mm.
Polypropylene materials, variety of choice
Multilayer and reinforced
AT recent times Among the reinforced pipes, the most popular are multilayer pipes with a fiberglass layer in the middle of the wall section. If you purchase just such material, then trimming the ends is not required.
Do-it-yourself welding of polypropylene pipes is carried out using diffuser soldering, for which you will have to purchase or rent a special apparatus. His choice will be discussed later. The welding process takes place at a temperature of 260 degrees, resulting in a very strong, completely homogeneous seam. The connection of blanks is carried out using tees, angles, couplings.
With metal parts - steel assemblies, taps, filters, mixers, counters - polypropylene pipes are connected using fittings with brass inserts pressed into them. AT threaded connections sealing materials must not form a thick layer. It is optimal to use a fum tape or linen with paste. The torque when tightening such connections should be moderate to avoid the metal element falling out of the fitting.
Do-it-yourself polypropylene welding: equipment selection
Tool shape
Soldering irons for welding polypropylene products are divided according to the shape of the working body into rod and sword-shaped (flat). Based on my own experience, I can say that it is more convenient to work with a soldering iron in cramped hard-to-reach places.
Soldering iron power
The power of the tool can be approximately selected based on a simple calculation. To do this, multiply the diameter of the pipe in mm that you are going to solder by 10. For example, to weld a product with a diameter of 50 mm, a power of 500 W is sufficient.
Quality and functionality
High-quality soldering irons of the professional range have electronic adjustment, which allows you to achieve good accuracy in setting the heating temperature. The sound signaling gives the chance of control of process in all three modes: heating, connection, fixing.
Nozzles for soldering irons
There are two types of soldering iron tips: Teflon and metallized Teflon. The latter has higher strength characteristics. However, if the Teflon nozzle is handled carefully - carefully put the tool in a case, wipe pipes and fittings with alcohol or other degreaser before welding - its service life will be quite long.
Manufacturers of equipment for welding plastic materials
Do-it-yourself welding of plastic pipes, of course, will be greatly facilitated when using high-quality ones. The most desirable, but also the most expensive option are Czech-made soldering irons. Turkish and Russian models are much cheaper, somewhat lower in performance than Czech ones, but for home use they are quite an acceptable option. Often negative reviews were received by models that, when carefully checked, turned out to be Chinese fakes. One thing can be said about Chinese soldering irons - the cheapest ones are suitable only for short-term, rare use.
Advantages of using polyethylene pipes
Do-it-yourself welding of polyethylene pipes differs from similar work with polypropylene materials.
Polyethylene materials have a number of significant advantages:
- first of all, it is flexibility, which makes it possible to lay nodes along a curved line without joints between straight segments;
- light weight, the ability to fold during transportation;
- the material is completely inert, does not interact with any substances in the ground;
- does not emit toxic elements;
- does not break in the cold.
PND polyethylene pipes can be used for water supply and sewer systems. Such parts do not wear out, do not corrode, do not overgrow, are not afraid of contact with aggressive substances and, most importantly, can change their length by 7% without losing performance characteristics. Bandwidth this type of water supply is 30% higher than that of a metal counterpart with the same cross section, due to the ideal smoothness of the walls.
Electrofusion machines for welding HDPE pipes
Do-it-yourself welding of HDPE pipes is possible using an electrofusion joint. In such welding, special fittings are used, in which heating elements are mounted during manufacture. These can be elbows, saddles, tees and plugs. To connect products with embedded heaters, special electrofusion devices of the most varied degree of complexity and equipment are required.
If you want to use polyethylene pipes and not bother yourself with finding suitable equipment, then you can purchase PE pipes. They are intended for internal and external water supply, sewerage, drainage. Small diameters of such pipes (up to 63 mm) can be assembled using brass or polypropylene fittings with rubber rings for sealing.
If you decide to replace or mount on your own new system water supply or heating, using plastic products, then this will be quite within your reach. But for the successful completion of the task, it is necessary to familiarize yourself with the basic principles of connecting the selected pipes and be sure to consult with professionals.
How to solder pipes? In the article, we will analyze the technology for connecting pipes and fittings made of copper, polypropylene, polyethylene and PVC. We are interested in both the technology of soldering connections and the necessary tools for this.
Copper
The exceptional reliability and durability of copper is well known. It is not subject to corrosion, does not overgrow with deposits and is not afraid of heating to high temperatures. Actually, suffice it to say that the oldest copper plumbing has been in use for more than a century.
However: copper is a relatively soft metal.
Accidental mechanical damage to the water supply is quite possible.
In countless videos posted on the Internet, soldering copper pipes is shown and described in sufficient detail. Let's pay attention to those moments that are often left behind the scenes.
Tools
To connect pipes by soldering, we need:
- pipe cutter. A simple tool will help cut the copper tube strictly at right angles to its axis, thereby ensuring maximum connection reliability.
- Chamfer. With it, burrs are removed from the inner and outer edges of the pipe.
- Pipe Expander. It helps form the solder sleeve. Of course, this tool is needed only where they are not used.
Attention: the formation of a sleeve is only possible on annealed copper.
Without annealing, the metal is not ductile enough.
- Burner. It can use propane or acetylene. In domestic conditions, burners designed for use with small disposable cylinders are most convenient.
In addition, flux and solder are needed. At home, the use of so-called tin-based soft solders is optimal.
Technology
- The surfaces to be soldered are cleaned of dust and, if necessary, degreased with acetone.
- A sleeve is formed using a pipe expander. The gap diameter between the inner surface of the sleeve and the outer surface of the next pipe should be minimal - no more than 0.125 mm. The length of the sleeve is not less than the diameter of the tube.
- A small amount of liquid flux is applied to the surface with a brush.
- The sections of the water pipe combined with each other are evenly heated by the burner. When in contact with copper, the solder should melt.
- With continuous heating of the joint, the solder bar is melted at the neck of the sleeve. The melt fills the cavity due to the capillary effect.
Polypropylene
How to solder propylene pipes? Of course, in this case, it is not difficult to find the corresponding video on the network - soldering propylene pipes is not too difficult and therefore is in great demand. Let's focus on the subtleties and nuances of this work.
Tools
- The apparatus for soldering pipes is a low-temperature soldering iron with interchangeable nozzles for different diameters.
Healthy: most of cheap soldering irons are devoid of a temperature controller and heat the nozzles up to about 260 degrees.
It is at this temperature that PP pipes are soldered.
The regulator is necessary when it is necessary to set a lower value for working with polyethylene.
- The presence of a pipe cutter is also desirable here. Outwardly, a pipe cutter for plastic pipes most of all resembles a garden pruner.
- In addition, soldering PP pipes with aluminum reinforcement requires a shaver (stripping) or trimmer. The choice of one or another tool depends on the location of the reinforcing layer.
Technology
How the actual soldering of propylene pipes is performed - the video in the training courses shows more than clearly.
- An appropriate nozzle is installed on the heating element of the soldering iron. corresponding to the pipe diameter.
- The soldering iron heats up to operating temperature.
- Then two operations are performed simultaneously: the pipe is inserted into the socket of the nozzle and at the same time the fitting is put on its narrow part.
- After 6-10 seconds (the exact time depends on the diameter), the parts are aligned with each other and held motionless for 10-15 seconds.
As always, the devil is in the details.
- Pipes with an outer layer of reinforcing aluminum foil are cleaned with several turns of a shaver - nozzles with knives inside. Shavers are produced both for manual cleaning and for a drill chuck.
- If the reinforcement layer is located between two layers of polypropylene, the preparation of the pipe is performed by a trimmer. The knives in it select a part of the pipe material from its end.
Explanation: stripping is needed so that all layers of the pipe are securely welded to the fitting, and aluminum does not come into contact with water.
Its electrochemical decomposition can lead to delamination of the water pipe section.
- combined in a reciprocating motion. Rotation is unacceptable: the resulting wave will weaken the connection.
- It is desirable to remove the outer chamfer on the cut pipe before soldering.
Polyethylene
Soldering of polyethylene pipes is carried out in two ways:
- Using electrofusion fittings. Inside each fitting is a high resistance conductor. Applying 12 volts to the contact terminals leads to its heating and reliable connection of the fitting with the pipe inserted into it.
- End-to-end, with preliminary melting of the ends of the parts to be combined.
The first connection method does not hold any surprises: soldering HDPE pipes (made of low-pressure polyethylene) is reduced only to assembling the water supply and short-term connections of the transformer to the terminals. Let's focus on butt soldering.
Tools
It is worth mentioning one subtlety. Normally, the butt-soldering technology for HDPE pipes is used for large (from 50 millimeters) diameters and uses fairly sophisticated equipment for centering and clamping. However, the method can also be used for welding pipes in country water supply systems, irrigation systems and other pressure systems with moderate pressure.
Actually, the toolkit differs little from what is needed to connect polypropylene pipes.
- Soldering iron. It is better to use devices with temperature control: soldering polyethylene pipes requires heating not up to 260, but only up to 220 C.
- Pipe cutter. The ends must be strictly perpendicular to the axis of the pipe.
Technology
Actually, the soldering of HDPE pipes is even simpler than in the case of polypropylene.
- The ends are pressed tightly against both sides of the heating element of the soldering iron and held until a burr appears - a roller from the plastic melt.
- Then they are combined and held for a minute in a static position.
Attention: it is better to use a soldering iron with a Teflon-coated heating element.
Otherwise, part of the plastic will remain on its surface and, believe me, the air will not ozonize.
PVC
What does soldering PVC pipes look like?
Stately - no way. Generally. Both pressure and non-pressure water pipes and elements of sewer systems are connected only by sockets, using glue or rubber seals.
On the picture - pressure pipes from polyvinyl chloride. The tightness of the connections is ensured by rubber seals.
However, in some cases, soldering PVC pipes in free-flow sewers is still practiced. Typical situations are a breakdown of the siphon elbow in the late evening or the need to make a fitting of a non-standard configuration.
Like any thermoplastic, PVC can be melted and bonded relatively securely by molecular diffusion. It is clear that buying a special soldering iron will be some overkill.
How to manage improvised means?
- The blanks are cut to size with a hacksaw or, which is much more convenient, with a grinder with any cutting wheel.
- The edges of the joining parts are slightly melted over the stove or in the flame of a gas burner and pressed against each other.
- Then the seam is melted in a circle with a table knife or any other metal object heated to a dull glow.