27 Jan Features of mounting compression fittings on HDPE pipes
Installation of pipelines using inexpensive and reliable compression fittings does not require the use of specialized equipment and is a progressive alternative to butt and thermistor welding. Compliance with simple rules when assembling compression fittings guarantees a long service life and trouble-free operation of the created pipeline.
1 – a clip nut, 2 – ring for a clamp, 3 – ring for the stop, 4 – compression ring, 5 – fitting case.
Fittings for compression type pipes are made from an ethylene copolymer according to the casting method and are resistant to temperature extremes and the effects of a wide range of chemical agents. Polymer accessories for pipes are used to create drinking water and automatic watering systems, technical water supply and hermetic channels for laying communications.
Structurally, a compression type fitting is a design of separate modular elements—a plastic case, sealing laying, sleeve, a squeezing ring and a lid nut. For all products from a group of compression fittings (couplings, adapters, tees, etc.) The standard design is characteristic, depending on the brand, only the quality and durability of the accessory related to the type of raw materials are distinguished.
In addition to fully collapsible models, partially collapsible polymer fittings are presented on the market (clamping and compression rings are combined into one). At the moment, there is no data that clearly provides the advantage of a particular structure. The main advantage of fittings with partial disassembly is the increased speed of their installation and dismantling during repair.
Compression fittings are suitable for PND pipes of brands PE 80 and PE100 and are made with a diameter of 16 to 63 mm., working pressure can be from 10 to 16 bar.
The pluses of compression fittings
Inexpensive and quick installation. To install fittings, preliminary preparation of the pipe or special skills is not required;
Simplicity of repair. In case of breakdown, only one of the internal elements of the fitting is replaced;
Reusable use. In Mobile Casino, the difference from welded structures, PND fittings are easily dismantled and installed again using a compression key (they are able to withstand up to 10 assembly cycles);
Insensitivity to corrosion. Do not contain parts made of metal and are not subject to corrosion processes;
Health safety. Produced from environmentally friendly materials that do not emit harmful substances and are suitable for use in drinking water transport systems;
Universality. They have a standard design and thread type, therefore they are suitable for mounting pipelines made of different materials (steel, aluminum, PVC, copper).
Installation of compression fittings
Assembly of compression fittings requires much less time than welding, but has its own nuances. If the rules for installing fittings are violated, the resulting connection is unstable and quickly fails.
Scissors or knife;
The main stages of installation
The pipe is cut with a knife or a hacksaw and processed with a beveler (for products with a diameter of more than 50 mm. knife is used). The ends of the cut pipe should be as even as possible – this configuration allows the edge of the pipe to tightly connect with the protrusion inside the fitting and form a sealed joint;
With the help of the FACCOSITER, the end of the pipe is embedded in the form of a cone and smoothed out to remove ZAZUBRES and other defects. The cone-shaped smooth end provides the ease of introducing the pipe into the inner ring of the fitting;
A white marker on the pipe is placed risks noting the necessary depth of introduction into fitting. Marking guarantees that when assembling the end of the pipe will reach the required point in the fitting case;
After applying the crook, the pipe must be covered with lubricant for light introduction into a sealing ring (relevant for pipes with a diameter of more than 50 mm.);
Before installation, the fitting is understood on the basic elements. In order to avoid deformation or loss of small elements, it is better to prepare a separate surface for them;
The installation of fitting elements is carried out in the same order as dismantling – first a nut (first removed element) is installed, then tsang, etc. P. After all the elements of the fitting are connected in one piece, it is necessary to tighten the accessory and fix the nut;
To install partially collapsed fitting, it is enough to slightly unclench the clamping nut. After the pipe is entered into the fitting to the desired mark, it is necessary to fix the nut using two compression keys.
If it is necessary to create a branch from the central pipe, it is recommended to use not a standard tee, but a compression clamp (a saddle clamp). Creating three separate compounds, the tee significantly increases the risk of leaks. The saddle clamp is installed in a hole cut into a pipe using a drill, and is tightly fixed by a sealing ring that provides a reliable sealed connection.