Installation and maintenance of a water supply system requires a number of specific procedures, one of which is the soldering of HDPE pipes. For its implementation, specialized tools are used. There are also rules for conducting such procedures that must be followed to achieve the best result.
Choosing a method for soldering HDPE pipes
There are several basic methods for soldering HDPE pipes. Different methods are preferred for different working conditions. All of them have pros and cons, which often complicates the choice. However, information about specific conditions will help determine the type of soldering.
In many cases, when installing a pipeline, it is very important to maintain the flexibility of the entire section. Any rigid non-bending elements can complicate operation. In this case, butt welding is the best choice. It is quite simple to implement and does not require expensive components.
Carrying out work in hard-to-reach places involves coupling soldering. It will help connect sections of the pipeline, even if they are absolutely motionless relative to each other.
The electrofusion method will come to the rescue when a connection is planned in a very cramped space. Also, this method is considered one of the fastest, which can be a fundamental factor when choosing.
Important! If the parts need to be connected for the duration of any work and a permanent connection is not expected, then it is more logical to use not soldering, but a conventional detachable connection.
Butt welding of polyethylene pipes
The most common way to connect HDPE is butt welding. It is really very economical and easy to use. In addition, it provides a sufficient connection resource. To implement the method, specialized welding equipment is required. The method is suitable for those places where the pipes move freely enough and where it is desirable to leave this flexibility.
The method can be used for open laying of pipelines, as well as in trenches.
Butt welding procedure:
- The two parts are installed in the holder of the welding machine, which guides the products against each other without displacement.
- Further, the aggregates are fixed in the holder with clamps.
- Using an alcohol solution, the edges must be cleaned of various contaminants. It is advisable to use materials that do not leave a lint behind.
- With the help of trimming, the edges are also processed mechanically. They are given the appropriate form. Processing is carried out until a chip with a thickness of less than 0.5 mm appears.
- Then the master needs to manually check the ends for parallelism. If there are gaps, then the trimming procedure is repeated.
- The heating element simultaneously heats the ends of the products to be joined.
- As soon as the edges have melted a little, the heating stops, and the products themselves are tightly connected to each other. The parts are pressed until the connection has sufficient strength. In most cases, 5-10 minutes is enough.
- After carrying out the work, it is necessary to carefully examine the weld, and also make sure that the connection is strong.
The final quality of the soldering depends very much on the quality of the preliminary work. Well-cleaned and prepared edges are much better soldered together. Thus, it will be possible to achieve a very good result.
Important! Butt welding is necessarily carried out using one seam. Otherwise, the strength and durability of the connection will be minimal.
Socket welding of HDPE pipes
Socket welding has a different procedure and a different set of materials. To carry out the work, you will definitely need a soldering iron for HDPE pipes, as well as a set of nozzles. Often such connections use additional hardware, such as angles and eccentrics. The connection of the ends of the products is carried out after the fittings are attached to them.
The work uses a soldering iron for polypropylene pipes, which contains several metal parts. These parts heat the plastic aggregates. One of them is a mandrel — a special element that is inserted into the inside of the fitting. The other, the sleeve, serves to heat the site itself.
Socket welding requires special training. It is necessary to carry out a number of actions to help improve the quality of the connection:
- The blanks must be trimmed and set exactly opposite each other.
- The edges must be cleaned of dirt and plastic residues.
- Those pipes that are not currently in use must be plugged with plugs to avoid clogging.
- It is necessary to inspect the soldering iron for contamination or plastic residues from past work. Clean if necessary.
After carrying out all the preparatory work, you can safely take up the implementation of this welding method. Implementation order:
- The parts to be joined are heated by a soldering iron to a certain temperature. Usually, this temperature is monitored by the device itself, which at the right time will give a signal to stop heating.
- The pipe is forcefully inserted into the sleeve, and the fitting is pushed onto the mandrel. Often, these operations require quite a lot of effort. It is necessary to insert the parts until it stops.
- The excess plastic will be squeezed out and create a ring-shaped roller.
- Then both parts must be removed from the tool and tightly connected to each other.
- After complete cooling, you can continue to work on connecting the pipeline.
Important! During cooling, it is necessary to ensure complete rest of the connection. Any impact at this stage can break the tightness of the connection.
The duration of soldering can be found in the standards, in which this time is indicated depending on the diameter of the parts.
It must also be remembered that it is necessary to apply force when connecting the pipe and fitting only until the parts have rested. If you continue the impact, you can violate the integrity of the connection, which will cause negative consequences in the future.
A special type of socket welding, which consists in the use of special equipment. Such a connection helps to achieve high strength and durability of the finished structure. The method is implemented using electric couplings, in which heating elements are already located inside.
Fittings with heating elements in the inner part can be used. Spirals heat up the material, making it plastic. Then the two parts are joined together and a reliable monolithic connection is provided.
Tools for such welding are much more expensive, but functionally much better. The use of electric couplings ensures that there are no ring beads in the interior and ensures good water flow. Another advantage is that this method does not require the direct use of welding equipment. This helps to work in tight spaces.
The procedure for electrofusion welding:
- The connected parts are cut in the right places.
- The ends of the products, as well as the electrical coupling, are cleaned of contaminants.
- Appropriate marks are left on the surface, which should help determine the depth of insertion of the coupling.
- With the help of wires, the electric coupling is connected to the welding equipment.
- On the device, the master presses the button to start welding, which will start heating the elements.
- Once the process is complete. The device will automatically turn off the heat.
- After about an hour, the connection will have completely cooled down and can be put into operation.
Before welding, it is best to cover the ends of unused pipes with special plugs to avoid cooling.
While welding, it is important to keep the parts in a rigid position. This can be done using special holders or stands. The final weld should not be thicker than 0.5 of the wall thickness.
Necessary equipment and tools
Soldering pipes made of HDPE is impossible without the use of a number of special devices. The most important thing in this case is the welding machine. It is a special device in which the heating element is located. Holders for various nozzles depart from this element. It is these nozzles that are used to melt the material.
Butt welding of polyethylene pipes also requires special measuring and alignment components. They are necessary for a clear fixation of products opposite each other.
Typically, cooking appliances are not used at home. They are used in industry, as well as by professional plumbers. This is due to the increased complexity of such work and the risk of leaks. But sometimes such work can be done by hand. After all, if you follow simple rules, then all risks will be minimized.
Together with a soldering iron, for the work you may need:
- professional pipe cutter;
- means for degreasing and cleaning surfaces;
- marker for marking.
Scissors or a pipe cutter often come with a soldering iron, so you probably won’t have to purchase one separately.
When socket welding, you will also need a separate set of fittings of different sizes. These can be straight or angled couplings, taps, distributors or tees.
Other pipe soldering tools are sometimes used to help the craftsman get the job done as efficiently as possible.
How to solder polypropylene pipes in hard-to-reach places
Hard-to-reach places for welding usually include the space under the ceiling, points in the corners and limited spaces in which it is impossible to install the soldering iron on a stand.
The problem can be solved by using a hook that can support the weight of the soldering iron. A tool is hung on it, and work is carried out in this position. Also, in conditions of constraint, electrofusion joints have found wide application. They do not require the installation of a welding machine in the immediate vicinity of the parts to be welded. Only fittings for soldering HDPE pipes are used, which are connected to the device with wires.
If the pipes to be welded are very close to each other, then the method of alternately heating the ends is used. First, one end is heated to a higher temperature than necessary. Then the second part is heated up, as quickly as possible.
Important! Sometimes it is necessary to solder two pipes without changing their length. Then swivel fittings will help, which will help solder the pipes in different planes, and then connect them.
Soldering in the corners is carried out with increased attention to all measurements. It is very important to maintain a right angle here so that the flow of the fluid is not disturbed. Couplings with a turn angle of 90 degrees are used. In general, the welding methods are identical to the conventional straight section. It is recommended to purchase couplings and pipes from the same manufacturer. This makes it possible to achieve a better match of the soldered materials.