METHOD OF INSTALLING HEAT-SHRINKING COLLAR ON SIPHON JOINTS Russian patent published in 2025 - IPC F16L1/28 F16L13/02 F16L58/04 

FIELD: protection of underground pipelines.

SUBSTANCE: invention relates to protection of underground pipelines against damage, as well as soil and atmospheric corrosion during their construction and repair. Disclosed is a method of installing a heat-shrinking collar on the joints of the siphon, which includes applying a heat-shrinking collar to the weld seam of the siphon and heat treatment of the obtained connection. At that, prior to application of heat-shrinking collar on the welded seam of the siphon, preliminary preparation of the welded siphon sections is carried out by application of insulation with thickness of not less than 7 mm with subsequent cylindrical boring of ends of insulation, at which at distance of 100-170 mm from end of welded section of siphon insulation is removed completely to metal. Further, layer of insulation is removed up to 305 mm from the end of the welded section of the siphon. Thickness of the remaining insulation layer is 2.2-3.5 mm depending on the outer diameter of the siphon section being welded. Thickness of the removed layer is not less than 3.1 mm. Heat-shrinking collar is installed in a blind manner.

EFFECT: increasing the service life of the pipeline by eliminating the occurrence of “stripping” loads both on the edge of the collar and on its body.

6 cl, 3 dwg