Sealing spigot and socket pipe joints in situ. - partic. for low humidity high pressure gas pipelines

摘要

Sealing of a male-female pipe joint in situ comprises (a) applying a sealing cpd. around the joint having a flowable consisting and capable of adhering thereto, then hardening, solidifying or vulcanising, (b) applying a pressure exceeding the pressure inside the pipe, to the sealing cpd. to force the cpd., while flowable, into cracks or cervices of the joint, and maintaining this pressure during hardening, solidifying or vulcanising, (c) releasing the excess pressure on the cpd. after it has hardened or set, to leave it around the joint, incorporating the improvements whereby a two part rigid mould is clamped around the joint delimiting an annular cavity for the reception of the sealing cpd., and extending at least over a part of the female and the an exposed part of the male end of the joint, (d) the mould is provided with means for applying a pressure to the sealing cpd. until this has hardened or set, and is thereafter removed to leave the joint completely encapsulated in the thick annular ring of the rigid sealing agent.