Many people associate the word welding with sparks and bright light. Yes, this is true when welding. metal structures, but today we will look at a completely different welding - connection of plastic pipes using a welding machine.
I don’t know how it is for anyone, but when carrying out repairs on my own, with the advent of plastic water supply elements and this welding technology, a mountain just fell off my shoulders.
If anyone remembers how difficult it was to install water in the bathroom metal pipes or tie them, he will understand me. What was needed was not just a welder, but a very qualified welder who could weld very well and with high quality.
With the advent of this technology, everything has become much easier and can be done by anyone.
Let's consider connection of plastic pipes using the example of the most popular material - polyvinyl chloride, using a machine for welding plastic products. The main components of installation are pipes, fittings and the welding machine itself.
Of the necessary tools we will need
1. Welding machine for welding plastic parts (commonly called an iron).
It is a heating element with a handle and stand that allows you to cook in any position. It has an adjustment wheel that allows you to set the required heating temperature, a stand and holes in the heating element that allow you to attach nozzles of the desired diameter.
2. Paired nozzles coated with Teflon.
They are attached to the heating element and serve to simultaneously heat two parts to be welded. Depending on the diameter of the elements being welded, nozzles of the same diameter are installed.
These are special reinforced scissors, with the help of which the plastic is essentially cut through. The lower support jaw is stationary, the upper one is sharpened, descending to the lower one and producing a cut. Cutting scissors allow you to make cuts very accurately and quickly.
4. Tool for stripping (if aluminum-reinforced pipes are welded).
They are a head with well-sharpened knives, and when rotated, the top reinforcing layer is removed. The depth of stripping to the stop in the head determines the depth of welding.
When carried out frequently welding work It would be rational to purchase a complete welding kit, sold in a suitcase. Its average price in 2012 ranged from 2,000 to 3,500 rubles.
The kit includes the following items:
- A heating element;
- Four sizes (20, 25, 32, 40 mm) of Teflon-coated nozzles;
- Cutting scissors;
- Bolts for attaching nozzles to the heating element;
- Level;
- Stand for heating element;
- Hexagon for tightening bolts.
If welding work is carried out one-time, it would be more rational to rent welding equipment (in 2012 the price ranged from 250-350 rubles per day).
Let's consider the process of connecting plastic pipes or welding them
- We prepare the welding machine:
Set the temperature to 260˚;
We attach paired nozzles (if connections of different diameters will be used, install several pairs of nozzles);
We warm up the device to the desired temperature (when the operating temperature is reached, the indicator lights will light up).
2. Prepare the pipe and fitting:
We degrease the welding points (if the pipe is reinforced, remove the top layer of aluminum);
We measure the required length of the workpiece and cut it to the required size;
We mark the alignment on the elements to be welded with a marker for the correct location of the fitting relative to all other water supply structures.
We measure the depth of the nozzle into which the pipe will go and mark this dimension minus 2 mm.
Step 1. We take the pipe in one hand, the fitting in the other and simultaneously insert them into the nozzles.
Fit the fitting all the way, the pipe along the previously marked strip (not all the way, otherwise the end will heat up and when connecting, an influx will form on the inner diameter) and hold for a certain time (heating time column, sec). The specific holding time depends on the diameters of the products being joined and is indicated in the table below. When heating, rotation of parts on Teflon nozzles is unacceptable.
Outer diameter, mm. | Width of welded belt, mm. | Heating time, sec. | Connection time, sec. | Cooling time, min. |
Step 2. After warming up the parts, we connect them to each other, maintaining alignment and observing our marks for the correct orientation of the fitting relative to our welded structure. We insert the pipe into the fitting and make the connection very smoothly, without rotation. The connection time must not exceed the time indicated in the table for the selected diameter.
Step 3. We fix the welded assembly until the material has completely hardened for the time indicated in the table (Cooling time column, min.).
Plastic pipes are an excellent option that is suitable for replacing plumbing and heating systems. Their installation resembles a very exciting game rather than work, and the process of welding plastic pipes differs in many ways from traditional welding processes.
Peculiarities
Welding plastic pipes is heating the edges of the parts that are welded to a certain temperature. This process is performed using a special heater and connecting one part to another to a certain depth.
Besides, plastic pipes have some advantages:
- long service life;
- small mass;
- installation work is easy;
- low price;
- do not corrode.
Also, equipment for welding plastic pipes is cheaper than a welding machine for metal structures. In addition, even an inexperienced person can cope with such a process if there is an assistant.
The design parts are placed on pads specially made for this purpose. They heat up for some time to the desired temperature, after which the parts are removed from the pads and very quickly connected, while they need to be tightly compressed. The edges of the structure are soldered and form a single whole.
The process of welding plastic pipes also has its disadvantages. The main one is the possibility of formation of nodules inside the pipe. They appear if the temperature is too high, and this cannot be avoided when welding, so you need to carry out all work very carefully.
Too low a temperature will also not work - in this case, the parts simply will not be able to fully connect with each other. It turns out that it is very difficult to find the optimal temperature for soldering.
Tools
To perform welding work, you will need several tools.
- Welding equipment. This could be a special iron, a welding machine for plastic pipes, or a regular soldering iron. You can even carry out this process with a torch or a special gun.
- Soldering iron attachments. The most popular of them are models with a size of 20 mm.
- Special scissors battery type which are electrically driven. This tool has a fairly high cutting speed. With its help, cutting the pipe takes just a few seconds. If the amount of work is small, then you can use a regular saw or knife. Professionals also use special scissors.
- The seamer is a tool for cleaning the contour. It will be needed if the product is coated with a layer of aluminum.
- Bevel remover. Used when the contour quality is poor. It is used to prevent the plastic from lifting up. However, if special scissors were used, then it will not be needed, since with their help everything is done quite accurately.
- Cold welding will be needed in cases where a leak occurs somewhere and it is necessary to quickly weld it in place.
- Fittings or couplings. They are selected depending on what connection is used.
- Tape measure with pencil or marker. Required for marking places of cuts and connections.
All tools can be purchased in specialized stores. However, when choosing a welding machine, you should take into account its high price. If it will only be used once, it is better to rent it.
How to solder?
To properly weld plastic pipes with your own hands, you need instructions. First you need to determine where the pipeline will be installed. It is advisable to draw up a plan so that the components that need to be welded are not located in hard-to-reach places. The easiest way would be to assemble the entire structure directly on the table, so that you can then secure it in an already designated place.
After this, you need to prepare the welding machine. It must be installed on a special stand called a clamp. Then you should make sure that its contact surfaces are not dirty. If there is still dirt, you need to wipe it with a cloth soaked in industrial alcohol.
On the temperature sensor, you need to set the temperature to 260 C. After this, the welding machine is connected to the mains, and the power button is pressed. Then it is heated for 15-20 minutes. When using for the first time, you must wait another 5 minutes. The pipe must be cut using special scissors at the marked location. Then a fitting with the diameter of the required size is selected. The end of the plastic pipe and the fitting must be inserted into the welding nozzle at the same time - they must be in the same plane.
Taking into account the diameter of the pipe, the temperature is added and maintained for the required time. After heating the elements, they must be removed from the welding machine and immediately connected. Then you need to keep them motionless for the recommended time. An hour after this, the pipeline is used for its intended purpose.
When the soldering is ready, it is necessary to check the knot for patency. To do this, it is blown or water is passed through it. If the soldering is done hermetically, it can withstand high pressure.
If the temperature is below zero, the plastic will be quite brittle and the joint will not be airtight, which can lead to both leaks and rupture of the pipeline. To prevent this from happening, a portable stove or heat gun is installed in the tent at the welding site.
Welding of large diameter plastic pipes. To solder large-diameter products, the size of which is more than 63 mm, you need to do joint-to-joint soldering. In this case, soldering is performed by melting the end pipes, as well as connecting them with great force. You need to ensure that all ends of the workpieces are perfectly straight. Thus, the solder will be as strong as possible and able to withstand high pressure.
Socket or coupling solder. Plastic pipes with a diameter of up to 40 cm are soldered using special device manual type. It consists of a centering device, as well as attachments for fixing workpieces. The end of the cut piece of pipe is cleaned either with a file or sandpaper. The welding machine is heated and all the parts of the future pipeline are driven into it, then soldering is carried out. Everything must be done quickly, while the material is at the required temperature.
You also need to pay attention to the fact that with socket welding, the inner diameter of the unheated fitting must be less than the outer diameter of the pipe. After welding, some time is allowed for cooling, and the elements cannot be moved or turned over to avoid deformation.
Welding of reinforced pipes. Such pipes are used for heating systems. Before starting work, it is necessary to clean the aluminum layer using a seamstress. This is done so that during the process of operation, in contact with water, the aluminum foil cannot be destroyed and also does not leak.
Welding polypropylene pipes using an industrial hair dryer. This method is used only in some cases. For example, to connect two sections of pipe, produce shaped parts, install an elbow from individual elements. When connecting plastic, an industrial hair dryer is equipped with a reflector, that is, a nozzle with a special coating. This is done so that the molten metal does not stick to it.
When the hair dryer is installed on a table surface, it should be set to minimum air flow. The nozzle is heated to the desired temperature and then pressed against the ends of both plastic blanks. When the polypropylene has softened, the pipes must be connected. The parts are held in this position for approximately 30 seconds. After this, they will stick to each other and harden. This welding is very strong and durable.
Welding plastic pipes in inconvenient places. Of course, it is much easier to solder pipes on straight runs. As for hard-to-reach places, in order to avoid unpleasant moments in the process installation work you need to assemble the pipeline directly on the table surface. In cases where it is necessary to solder pipes in very inconvenient places, for example, under the ceiling or near a battery, you cannot do without the help of another person.
When all the parts plastic pipeline will be assembled, you can begin to connect the knot in weight. Here, too, an assistant is needed to hold the welding machine while the parts are connected. If the assistant also has at least a little experience with welding, you can do this alternately, which will make the work a little easier.
Everything needs to be done quickly and accurately, and if there is the slightest distortion, the damaged element must be replaced immediately. The most important point is compliance temperature regime, because when plastic pipes overheat, loss of shape may occur, which can cause problems during installation work.
When starting to weld water pipes with your own hands, you need to listen to the advice and recommendations of specialists. They will help turn mechanical movements during welding into a deliberate process.
If welding work is being carried out for the first time, then it is necessary to practice a little before starting the installation of plastic pipes. After cutting the pipes, there will be unnecessary pieces left that are quite suitable for training. Everything needs to be done as in a full-fledged process.
You need to train until your hand is full. If fittings are used, you can solder a couple of elements to them. You shouldn’t skimp on one or two fittings for training, because then you can ruin the whole pipe, which is many times more expensive.
It is necessary to purchase materials with a small reserve, as they can be damaged even before work begins. Even experienced specialists are not immune from any force majeure, let alone a beginner. Therefore, it is better to let some element remain after the work is completed.
When connecting structures with a small diameter, you need to ensure that sagging does not form in the middle due to overheating of the material. In this case, the passage may become clogged and water will break through the system. Therefore, before starting it is necessary to blow out water pipes air.
In addition, there are many more cases where non-compliance with the rules can lead to similar leaks or blockages in the system. For example, incorrect insertion of the pipe into the fitting, that is, not all the way. In this case, a gap will form between the walls of the pipes, and normal loads will be too great, which can lead to leakage.
You can also test the quality by pressing on the pipe or joint. The design must withstand such a test. If it doesn’t hold up, then it will not last long during operation. Therefore, purchase polypropylene pipes only from suppliers who have a good reputation - in this case, you don’t have to worry about the structure eventually bending or breaking under pressure.
Having assembled the entire system, you need to start using it no earlier than at least one hour has passed. This period of time will be enough to harden the seams. You should not remove melts while welding is in progress - this will lead to even greater deformation of the pipes, and such a process will be irreversible. After heating, polypropylene cools down quite quickly, so slowness in welding is unacceptable.
When it is necessary to replace old water supply or heating pipes, owners most often give preference to modern plastic pipes. Plastic pipes have many advantages, among which the ease of installation deserves special attention - you just need to follow the instructions and remember a few important nuances.
The installation of plumbing and heating using plastic pipes can be done with your own hands. However, before you start carrying out any activities, you need to learn how to weld plastic pipes yourself - you definitely won’t be able to do it without this skill.
Before starting work, read a few important recommendations and prepare the necessary equipment.
- If you have no experience welding plastic pipes with your own hands, first practice a little. Buy fittings and other wiring elements with a small margin. Once you gain experience, you will be able to complete the finishing work as quickly and efficiently as possible.
- Before starting work, the joining elements must be properly prepared - cleaned and degreased. Without pre-treatment, you cannot count on a high-quality welded joint.
- During the wiring process, you will use not only pipes, but also various additional devices - turn signals, tees, couplings, etc. Remember: pipes must be heated from the outside, and all additional elements from the inside. Do not ignore this rule, otherwise the finished connections will be fragile and short-lived.
- When welding plastic pipes with your own hands, especially if small parts are used during the work, make sure that the internal seams do not reduce the permeability of plastic products.
- Typically, this problem occurs when the pipes overheat - too much material builds up inside and the holes become clogged. Therefore, plastic pipes can only be welded at permissible temperatures (indicated in the instructions for the soldering iron). After completing the work, be sure to check the pipes for permeability. To do this, simply pass water through the product.
- The assembled system can be filled with water no earlier than 1-1.5 hours after welding the components.
Required Tools
Prepare the following equipment:
All necessary tools sold in construction stores. A soldering iron is quite expensive, so if the work of welding plastic pipes is one-time, it will be more profitable to find a company that provides such tools for rent.
Welding Guide
Welding plastic pipes is a simple task that you can do yourself. You just need to go through each step of the guide step by step.
The first stage is preparing parts for welding
Start by preparing the elements to be joined. Cut the pipes according to the requirements of the pre-prepared wiring diagrams. Arrange all the cut elements in the order in which they will be connected using a special soldering iron. This way you will avoid the risk of incorrect connection of elements of the pipeline system.
Remember: if unsuccessful threaded connections unscrewed and remade without any problems, then the seams will no longer be able to be taken apart. Products with defective connections will simply have to be thrown away. Therefore, be careful and careful.
The second stage is setting up the welding tool
The design of the soldering iron requires the presence of a temperature regulator. Set the regulator to the limit recommended by the manufacturer in accordance with the attached instructions. You can tell that the soldering iron has heated up to the set temperature when the temperature control light goes out.
The third stage is heating the elements
Before welding begins, all components of the future pipeline must be heated. Information on recommended conditions and optimal duration and preheating is given in the instructions for the soldering iron. Be sure to check it out.
To heat the parts, they must be inserted into the connectors of the welding device. You will also find information on how to do this correctly in the manufacturer's manual for your soldering iron.
The fourth stage - connecting the elements
Correctly heated parts are connected very quickly and smoothly. During the connection process, no distortions or rotations of the elements should be allowed. When connecting two sections of plastic pipe, strictly maintain the cut angle - only in this way will the seam you create be tight and reliable.
Fifth stage - stripping connections
Let the seam cool and carefully sand it down. You can use a file for cleaning.
Thus, there is nothing super complicated about welding plastic pipes yourself. Use high-quality tools, follow the recommendations received in everything, and very soon you will be able to use your own plumbing or heating system.
Good luck!
Video - Do-it-yourself welding of plastic pipes
Almost all modern communication systems are made from polymers. One of them is polypropylene pipes, which have become especially popular when creating home plumbing. The features of welding PVC pipes will be discussed in our article.
Pipes made from polyvinyl chloride have a smooth surface. Thanks to this, the water supply from such pipes will never become clogged.
The advantages of using PVC pipes include:
- resistance to the negative effects of chemical environments;
- resistance to corrosion and rotting;
- light weight;
- ease of installation work;
- long operational period (up to 50 years);
- reasonable cost.
Equipment for welding PVC pipes you will need:
- soldering iron with nozzles (selected depending on the diameter of the pipes);
- scissors for cutting pipes - pipe cutters (must be sharp enough so that when cutting pipes there are no burrs or other damage);
- chamfer.
Pipe welding methods
There are two main technologies for soldering water pipes:
- using a soldering iron (the most common method);
- using special glue (so-called cold welding).
Both types of PVC welding are suitable for communication systems that do not require high pressure when passing water.
If water will be used as a coolant for the heating system, then soldering of the pipeline can be carried out:
- sleeve welding (with welding of fittings, couplings or other connecting elements);
- electrofusion welding (as a result of melting the connecting parts, reliable welding with the pipes occurs);
- butt welding (when using too thick pipes that heat up to 220-260ºС and are connected to each other).
All these three technologies boil down to the fact that reliable adhesion of pipes occurs when they are exposed to high temperatures.
Preparatory stage
Regardless of the welding technology, you should properly prepare for this process. At the initial stage:
- a detailed plan is drawn up indicating the location of water pipes;
- the amount of material (pipes, fittings, other fastening elements) is calculated.
Thanks to a diverse range of fittings, the pipeline system can take on any configuration.
When purchasing directly, you should not pay attention to pipes that are too cheap (in most cases these are Chinese-made products). This is explained by the fact that during the first inspection it is difficult to detect a defect that may appear during the soldering process of the material.
Therefore, it is better to give preference to products famous manufacturers pipes, which include products:
- Banninger;
- Wefatherm;
- Aquatherm;
- FV-Plast;
- Ecoplastic.
The same applies to PVC welding equipment. Before purchasing, you should make sure that it will function effectively at an optimal temperature of 250-260ºC. It is clear that due to the high cost, it does not make sense to buy a soldering iron REMS MSG-63FM Set 256231. In terms of price and quality, the following devices are quite suitable:
- Gerat Weld 75-110 69110;
- BRIMA TG-171 0010291.
There is a conditional calculation of the suitable power of the machine for welding PVC pipes, which is compared with the diameter of the pipes used. The minimum power of the equipment should be equal to the diameter of the pipe multiplied by 10. That is, if pipes with a diameter of 50 mm are used, then the soldering iron should have a power of 500 W.
Welding work
Immediately before welding it is necessary:
- clean the pipes from dirt and dust at the soldering points and degrease them with alcohol;
- make marks on the pipes that will be connected by fittings (in places with turns and branches);
- chamfer the ends of the pipes.
The process of soldering PVC pipes itself consists of four main stages:
- cutting material;
- heating it to the optimal temperature;
- pipe connections;
- cooling the material.
The pipes are cut using a pipe cutter. It should be noted that the soldering of pipes with fittings should not occur too tightly. When they are connected, a reserve is created equal to twice the depth of the pipe entry into the fitting.
There is no need to use extra force when connecting pipes. They can cause rings to form between the inside of the fitting and the end of the pipe. Due to the appearance of such rings, the force of water flow will decrease.
When welding PVC with your own hands Special attention attention should be paid to heating the elements to the optimal temperature (250-260 ºС). If this is not done, the joints will end up with defects. During normal heating, internal tension in the pipes is created at the soldering points, which is necessary for the quality of the process. Welding must be done quickly enough. After which the connection cools down for 15-20 minutes.
PVC welding is carried out at temperatures above -3ºС. If the temperature is too low, the pipes will have to be heated for quite a long time. And the strength of the pipe connection will not be of sufficient quality.
The room where pipes are laid must be clean. The presence of dust or dirt in the solder joint will lead to a significant loss of welding quality.
Features of the use of cold welding
Cold welding of PVC involves the use of a special glue that contains chlorinated polyvinyl chloride. The working composition must have a uniform consistency and be fluid. Under the influence of glue components, 1/3 of the internal thickness of pipes and fittings is dissolved.
Work is carried out on warm days. If the weather is hot, the gluing process must be carried out in a short time. The glue should not dry until installation work is completed. During breaks in work, the container with glue is tightly closed with a lid. This is the only way the volatile components of the composition will not evaporate.
Cold welding of polyvinyl chloride pipes involves performing the following sequential actions:
- the pipe of the required length is cut;
- a chamfer is removed from the ends of the pipe at an angle of 15º (without the appearance of burrs);
- the pipe and fitting socket are cleaned of moisture, dust and dirt (a cleaner for PVC pipes is best);
- glue is applied to the surface of the fitting and pipe with a brush;
- the pipe is inserted into the socket;
- the fitting rotates 90º (for uniform distribution of glue);
- the connected parts are fixed and held in one position for 1-2 minutes;
- check the uniformity of glue application around the pipe;
- excess composition is removed with a soft cloth.
Video about welding PVC pipes:
When installing plastic pipes with a socket, as a rule, welding of PVC pipes using the gluing method is used. This joining method is also called “cold welding”. We will devote our article to its consideration.
Methods for connecting plastic pipes
There are several known methods:
- Chemical or adhesive.
- Physico-chemical:
- welding;
- fusion.
- Mechanical:
- threaded;
- using fittings.
Advantages of the chemical method over others:
- Increased efficiency and drainage.
- Reduces the risk of leaks that can occur when mechanically joining or butt welding pipes.
- Reducing the labor intensity of the process.
- Less energy consumption.
- Reducing material consumption.
- Low installation cost.
The adhesive method successfully connects pipes of various diameters: 6–400 mm.
Comparing adhesive pipe joints with welded and mechanical ones, you can notice some similarities and differences:
- In terms of speed, quality and low material consumption of the work carried out, the connection by gluing method is not inferior to traditional welding. However, unlike it, the gluing method does not use special equipment. The PVC pipe welding machine, which is used to construct a plastic pipe system, consumes a fairly large amount of electricity. Due to this, the cost of installing a pipe system using a welded method increases.
- A mechanical connection, like an adhesive one, is not as energy-intensive, but much more material-intensive. Using additional Supplies(various types of fittings) inevitably leads to an increase in the cost of installation work.
This is the difference in installation methods; based on it, you can estimate their complexity and choose the most suitable method.
Why and how to use “cold welding”
Features of “cold welding”
- The work uses an adhesive specifically designed for joining pipes and (fittings) made of chlorinated polyvinyl chloride (CPVC).
- The glue dissolves the surfaces of the parts to be joined by one third of the thickness, i.e. cold diffusion welding is carried out.
- A process such as soldering PVC pipes is influenced by various conditions:
- air humidity;
- temperature.
- Pipe gluing work can be carried out at a wide range of air temperatures: 5–35°C. The use of frost-resistant glue makes it possible to carry out work at temperatures down to –17°C. In hot weather, gluing should be done as quickly as possible to avoid the glue drying out before installation is completed.
- The properties of the adhesive should be:
- fluid;
- with a homogeneous consistency;
- without foreign inclusions.
The container with glue should be tightly closed with a lid during breaks between direct work to avoid evaporation of volatile components.
Adhesive pipe joining technology
Soldering PVC pipes into a socket is carried out in several stages:
- Exactly cut the required piece of pipe. For this the following can be used:
- a hacksaw for metal with fine teeth;
- pipe cutter;
- special scissors.
- Bevel the end of the pipe, maintaining an angle of 15 degrees, using a chamfer tool. Burrs should be avoided.
- Clean the fitting socket and pipe from dirt and dust, remove moisture.
A CPVC pipe cleaner can be used to effectively clean the parts being joined. It will prepare the surfaces well for gluing.
- Apply glue. The work is done with a brush carefully on the surface of the pipe and socket.
- Insert the pipe into the socket immediately after applying the adhesive layer.
- In order for the glue to be evenly distributed over the surfaces to be glued, rotate the fitting 90 degrees relative to the pipe.
- Fix the parts for 20–30 seconds. Do not re-rotate the connected parts after they have been fixed! The entire gluing process must be completed within 1 minute.
- Upon completion of gluing, check that there is a uniform layer (“roller”) of glue around the circumference.
- If necessary, remove excess adhesive using a soft cloth.
You can see the gluing technology more clearly in the video below.
Advantages of adhesive joints of PVC pipes
- Possibility of high-quality installation of plastic pipes even in places where access is difficult.
- There is no need to use expensive equipment that consumes a lot of electricity. The whole process can be done with your own hands.
- Directly in the process of gluing CPVC parts, a monolithic structure is formed, which guarantees the tightness of the joint.
- When carrying out adhesive “welding”, unlike conventional welding, no sagging is formed inside the pipe, which narrows the lumen of the pipes and contributes to the settling of solid particles on the surface.
- Compliance with simple rules and recommendations for carrying out work will eliminate the occurrence of sagging and leaks in the pipeline.
- The service life of a pipeline installed using the gluing method can reach 50 years.