METHOD TO REMOVE GAS LEAKAGE THROUGH FLANGE JOINTS OF GAS PIPELINES VALVES WHILE GAS TRANSPORTATION BY THE PIPELINE

This invention relates to repair of gas pipelines valves, mostly of high pressure main gas pipelines. A method to remove gas leakage through the flange joints of the gas pipelines valves while gas transportation by a pipeline comprises filling the inter-flange space and pin cups of the valve with sealing agent able to self-vulcanization. First, one makes a technological opening in the flange of the valve, with fixation of an additional valve in it; through this one the technological opening is continued to the inter-flange space or pin cup. After that, a syringe is attached to the additional valve, this is filled with sealing agent able to self-vulcanization beforehand; the sealing agent is inserted to the inter-flange space and the pin cups under pressure larger than the gas pressure in the pipeline. After filling the inter-flange space and the pin cups with the able to self-vulcanization sealing agent, the syringe is disconnected. After curing of the sealing agent, additional valve is removed and technological opening is closed. To prevent leakage of sealing agent through the cavities of the flange, the pins and the nuts at pumping it in, the pins and the nuts are at the outer side of the valve additionally treated by a catalyst.