The basis of the connection of water communications from plastic materials is the correctly chosen soldering temperature of polypropylene pipes. Modern technologies for creating wiring pipelines for water mains and heating from a similar material require precise temperature and time values in the process of welding. Deviations from the recommended data lead to breaks in the joints or deterioration of the water flow.
Soldering iron allows you to easily connect the ends of polypropylene pipes of any size.
The effect of temperature on the process of coupling docking pipes and fittings
The technology of soldering pipes made of polypropylene consists in the fact that before connecting them they are subjected to heating to a certain temperature, due to which softening of the plastics of joined parts is achieved. After their connection, diffusion of polypropylene molecules occurs, that is, a transition occurs at the molecular level between the two mating parts, as a result of which, after the material cools down, strong bonds are achieved within the hardened masses of plastic in the joint area.
Soldering technology of polypropylene pipes.
The value of the temperature regime has a direct impact on the strength of the welded surfaces of pipes. Insufficient heating, as a rule, leads to the fact that during the connection a sufficient diffusion process does not occur, the pipe body and fitting molecules cannot penetrate into adjacent areas, as a result, the soldering of parts does not withstand the loads and the pair breaks or the joint is not tight.
Overheating of the pipe and fitting leads to the fact that as a result of the joining, a critical deformation of the body of the parts can occur, which leads to the loss of their geometry or the influx of an excessive roller in the internal section. This causes a reduction in the diameter of the internal opening of the pipeline at the soldering point.
Polypropylene pipes for their joining should be heated to 255-265 ° C. This takes into account their diameter, ambient temperature and heating time. There is a pattern indicating the direct dependence of the diameter of parts and the time of their heating.
Technical parameters of soldering polypropylene pipes.
The value of the ambient temperature is important due to the fact that during installation there is always a pause between the moment of extraction of parts from the heating welding device and the moment of their coupling docking. To compensate for cooling at low temperatures, it is recommended to warm up polypropylene pipes a little longer. The additional time can be 2-3 seconds and is chosen empirically.
It is important to take into account that heating polypropylene pipes by setting the temperature on the heating device above 270 ° C at a reduced time will lead to rapid and excessive heating of the upper layers of the material and insufficient heating of its main body, which in the process of joining will cause too thin welding film.Back to table of contents
Basic heating instructions and time of exposure
Heating of the pipe and fitting is carried out in accordance with their diameters, and for each value it is necessary to adjust the heating time at a constant temperature on the heating element. The main criteria for the strength of the coupling:
- heating time;
- time of holding (fixing) the joint;
- cooling time before continuing work with the material.
Conditional periods of exposure time of parts of the pipeline on the heating element of the welding device:
|Diameter of pipe, mm||Heating time, s||Commit time, sec||Cooling time, min|
The instruction of a welded joint of polypropylene pipes provides for the creation of a welding belt (socket joint) of the required length. Usually its size coincides with the depth of the cylindrical nozzles on the heating element of the welding device, the shutter speed of the joint is achieved by complete installation of the pipe and fitting on the element body.
The temperature of the connected sections of pipes before the start of heating should not have negative values, since this will have to make very significant adjustments during heating.
Tools for soldering polypropylene pipes.
If you have to perform work at minus marks of the thermometer, then it is recommended to work with a warm material that was previously in a warm room.
A device for welding pipes is heated to 280-300 ° C, depending on the ambient temperature. This will avoid significant heat loss when they are transferred from the soldering unit until the moment of articulation. The amount of heat and its time is chosen empirically, making adjustments for 1-2 seconds.Back to table of contents
Some features of thermal exposure
Making calculation of schemes of pipelines, surely take into account step-by-step further installation. The increased distance between the soldering apparatus and the dislocation of the joint should be avoided. Sometimes there are miscalculations, which lead to the fact that you can not get to the welding site and you have to warm up at a considerable distance from it, as a result of which there are inevitable heat losses during the transfer of parts and their exact positioning at the joint. Such unrecorded moments lead to a weakening of the seam.
Type of wire when soldering, welding, twisting.
Errors in the sequence of soldering during installation often lead to the fact that the last joint cannot be produced due to the fact that the heating device cannot be placed between the parts. In this case, it is undesirable to deform the pipeline sections to increase the gap into which the apparatus can be inserted in the place of the future joint. This will affect the aesthetic state of communications and, possibly, will lead to static voltage in certain parts of the system.
The gross error that leads to loss of control over temperature is the sequential heating of parts before the joint, that is, the fitting and the pipe are heated separately. Such a technological approach completely eliminates the temperature condition and will cause either the first part to excessively cool due to the loss of time for heating the second part, or a significant overheating of the first part, intentionally produced to compensate for heat loss. This method of connection does not give complete control over the stage of softening of the material and is unacceptable.
The main criteria for precise temperature control are: high-quality apparatus for welding polypropylene pipes, allowing to maintain the specified values with a small error, the distance between the heating apparatus and the junction is not more than 1.5 meters, work in a relatively warm room, the same degree of heat of the two parts to be joined before their installation in the welding apparatus.