In regulating processes with reinforcement distinction: automatic and manual control, remote and local, continuous and periodic, infinitely variable and position.
The most perfect is the remote automatic continuous stepless control. The least perfect – manual regulation of the local periodical.
By way of joining pipe PEX fittings divided into flanged, threaded, tsapkovuyu, choke and with pipe weld (weld).
Flanged valves have the connections, fitted with flanges, socket – coupling with internal thread. PEX fittings for sewer networks can be threaded connections without internal thread, conical cavity which when combined with the pipeline are sealed with a rubber ring and filled with sealing material. Plumbing fixture has the connections with gasket seal and the outer thread, choke – with male thread without cushioning seal.
Reinforcement welding has the connections provided and prepared for welding to the pipeline.
Not all designs valves can be mounted in any position on the pipeline. In this connection, valves can be divided into construction, allowing for installation in any position, allowing for installation in a vertical position to a horizontal pipe and allow to install only on a vertical pipe.
The magnitude of the diameter nominal bore valves distinguish small passages (D y = 40 mm), medium hikes (D y = 50-250 mm) and large passages (D y> 250 mm).
The magnitude of the conditioned pressure valve can be divided into three main groups:
low-pressure P y <10 kg / cm 2 (1 MPa);
average pressure of 16 <P y <64 kg / cm 2 (1,6.6,4 MPa);
High pressure at 100 <P y <1000 kg / cm 2 (10.100 MPa).
Working conditions are determined by PEX fitting a large number of factors: the operating pressure of the medium, working temperature, physical and chemical properties of the working environment, fluctuations in pressure and temperature intervals execution cycles of operation, or switching, tape drive, the location of valves in pipelines located in the open or indoors , climatic conditions, etc.