PROCEDURE FOR CONNECTING STEEL AND POLYETHYLENE PIPES Russian patent published in 2010 - IPC F16L13/07 

FIELD: machine building.

SUBSTANCE: invention refers to pipeline transporting natural gas to consumers; it also refers to pipe accessories of pipes out of various materials. A socket is formed on a connecting part of polyethylene pipe; the socket maintains flow section of the pipeline at pipe connection and facilitates more reliable connection. The socket on a working part of a polyethylene pipe is shaped by heating its end and by pressing on a mandrel. Further the working part is pinched owing to which whole surface of the polyethylene socket adjoins surface of the steel pipe with a thread on the working part and a stop flange. A polyethylene coupling is pressed on the connection; then one of its ends is expanded after the stop flange of the steel pipe; simultaneously it is pinched according to the relief of the working section of the connection. Procedures for connecting the steel pipe with polyethylene pipe, for coupling pressing and their pinching are carried out with heated components of connection. To form the socket and coupling the polyethylene pipe is heated in a tank with a motor or transformer oil preventing polyethylene over-drying and cracking.

EFFECT: increased reliability of connection.

3 cl, 1 dwg