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On-line Inspection and Maintenance Succeeded on the Valve 7 of the Christmas Tree P302-3

Source: Date:Apr 22,2017 Clicks:857

Brief report from Puguang maintenance team:

The Puguang maintenance team of Western Union Petro successfully completed the on-line inspection and maintenance for the valve #7 of the Christmas Tree P302-3, with safe, high efficient and smooth operation. This is the first time in Puguang gas field to carry out on-line maintenance for the valves of S2S Christmas tree, which marked the new breakthrough in the on-line inspection and maintenance technology for the valves of high sulfur gas well. The historical problem of on-line maintenance for the valves in “Three-high gas fields” was solved, which win the consistent praise from the clients. And the clients gave the affirmation and praise for Western Union Petro’s technology.

The gate valve #7 could not work due to the corrosion on its elevation nut and it was treated many times by injecting grease and detergent but no effective result came, which affected not only the gas well’s production test and coiled tubing flushing operation, but also the integrity of the wellhead equipment.

Since the valve #7 in well P302-3 could not work and it was in closure condition, installing back-pressure valve to plug the tubing is not feasible, and then it had much more risks to replace the valves #1, #4 and #7 entirely. Meanwhile, for entire replacement of the valves, killing well was needed, which would take long time and big cost, easily contaminate the formation and affect the normal production of the gas well. Through comprehensive consideration, on-line maintenance and repairing the valve element might be taken to solve the problem on the valve #7.

Through on-line dismantling the valve parts and successful maintenance, the valve was agile and qualified in hydraulic pressure test, nitrogen gas seal and sour gas seal.

The on-line inspection and maintenance for the valves of Christmas tree can shorten the maintenance time largely, save cost for clients, change the possibility to remove the valves of Christmas tree and send them back to the factory, which obtained the clients’ praise.

leaders from the gas recovery plant visited the site to supervise the work

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Preliminary preparation work

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Dismantling valve #7 on Christmas tree

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Cleaning valve and screw rod

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On-line installing valve

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Recovering production and cleaning the site