Wellheads and Christmas trees: Is there a difference?

Both are vital to oil production, but they're not the same, and the 45-second valve close rule is there for a reason.

Bela Liptak
CG1508 ATE

Q: I work as an instrumentation design engineer on an offshore platform and have some questions. According to API RP14C, the response time for closing all the valves in the Christmas tree should not exceed 45 sec. What is the basis of this requirement? Why should all valves close within 45 sec? What would happen if they did not? We have a noise level limit of 85 dBA for these valves. Is that limit for the noise level up- or downstream of the valves? What is the straight-run requirement for these valves, and does that relate to the noise limit? M.Ulaganathanulaganathan.inst@gmail.com A: In oil and natural gas extraction, a Christmas tree, or "tree," is an assembly of…

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Voices: Ask The Experts

Wellheads and Christmas trees: Is there a difference?

Both are vital to oil production, but they're not the same, and the 45-second valve close rule is there for a reason.

By Bela Liptak

Q: I work as an instrumentation design engineer on an offshore platform and have some questions. According to API RP14C, the response time for closing all the valves in the Christmas tree should not exceed 45 sec. What is the basis of this requirement? Why should all valves close within 45 sec?…

Full Story

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    By Bela Liptak

    Q: I work as an instrumentation design engineer on an offshore platform and have some questions. According to API RP14C, the response time for closing all the valves in the Christmas tree should not exceed 45 sec. What is the basis of this requirement? Why should all valves close within 45 sec?…

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