For internal communications, pipes made of cold-rolled galvanized steel, copper and various polymeric materials are used: polybutylene, cross-linked polyethylene, polypropylene and PVC. Each type of product has its own performance requirements.
In the case of plastic pipes, pay attention to the following. Risers should be extremely flat without any distortions. Only a slight deviation from the vertical is allowed, which is 2 mm per 1 m of length. At the intersection of interfloor and wall ceilings, pipes are enclosed in fire-retardant sleeves made of roofing steel.
With vertical parallel laying between plastic communications and steel pipes for heating and hot water supply, the distance is left at least 100 mm wide. If the wiring is done using a copper pipe, the distance can be reduced to 50 mm. Structures made of polymeric materials are located below the pipes for hot water supply and heating. When crossing plastic and metal engineering systems, the minimum clearance between them can be 50 mm.
Long sections of communications are fixed using special fasteners-clips. The distance between the supporting elements is determined based on the type of pipe, the operating pressure in the network and the temperature of the pumped water. So, for horizontal pipes with a diameter of 16 mm, the distance between the fasteners is 110 cm, for a diameter of 25 mm – 140 cm, and for 50 mm – 155 cm. For vertically installed sections of the engineering network, the distance between the supports should be increased by 30%.
Copper pipes are fixed exclusively with brackets (in the vertical plane) and hangers (for horizontal installation). To reduce the noise level, all metal fastening elements at the points of contact with copper communications are equipped with rubber gaskets, which do not contain chlorine compounds.
When laying engineering networks inside building structures, pipes are placed in a special protective casing in the form of a corrugated pipe made of polyethylene or other materials without chlorine compounds. Naturally, PVC corrugations are unacceptable.
Such pipes are easy to cut and bend. So, products with a diameter of up to 22 mm with a wall thickness of 1 mm can be bent by hand without preheating. To exclude the presence of defects during molding, a spring of the appropriate diameter is placed inside the pipe. For products with an outer diameter of 12 mm, the minimum bending radius will be 42 mm, for elements with a diameter of 22 mm – 88 mm. Thicker pipes are given the desired shape by preheating them. The minimum curvature of the bend is equal to five pipe diameters.
After the installation is completed, the assembled communications are thoroughly washed, cleaning from various mechanical debris that could get into the pipes during installation. Before commissioning, be sure to test the pumping equipment and engineering networks of the cold and hot water supply system for possible malfunctions.
Tests are carried out before the installation of water-folding equipment (faucets). In this case, you should wait 24 hours from the moment of the last gluing and welding of pipeline parts. The pump is turned on in turn in idle mode and water pumping mode.
For four hours, while it is running, they check the balance of the wheels and rotors, the degree of heating of the electric motor, the presence of leaks at the joints of the pipes. The air temperature in the room and water in communications should not be lower than +5 degrees.
The level of test pressure in the network is 0.1-0.65 MPa during a hydropathic test and 0.011-0.3 MPa during a manometric test. If within half an hour there is no pressure loss over 0.02 MPa, and there are no drops at the joints, so the installation is done correctly.