دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: the conbul valves, pressure gauges, and chokes assembled at the top of a well to control the flow of oil and gas after the well has been drilled and completed. It is used when reservoir pressure is sufficient to cause reservoir fluids to flow to the surface.

n: The set of valves, spools and fittings connected to the top of a well to direct and control the flow of formation fluids from the well.


the control sections that sits above the basic wellhead. It may contain hangers, master valves, annular valves, wing valves, and gauges or pressure, flow rate or monitoring measurement equipment.

a four-way connection. In a wellhead, a flow cross connects the master valve and the swab valve with two, normally horizontal, connections to the wing valves.

a three-way connection. In a wellhead, a flow cross connects the master valve and the swab valve with the wing valve.

n: a specially fabricated length of casing or tubing usually placed temporarily above a valve on top of the casing- head or tubing head. It is used to run swabbing or perforating tools into a producing well and provides a method for sealing off pressure and thus should be rated for highest anticipated pressure.

n: A long, high-pressure pipe fitted to the top of a wellhead or Christmas tree so that tools may be put into a high-pressure well. The top of the lubricator assembly includes a high-pressure grease-injection section and sealing elements. The lubricator is i

a pressurized shell, mounted above the BOP or master valve, which houses the tool string when entering a live well.

n: see master valve.

n: 1. a large valve located on the Christmas tree and used to control the flow of oil and gas from a well. Also called master gate. 2. the blind or blank rams of a blowout preventer (obsolete).

n: A valve located on the Christmas tree that controls all flow from the wellbore. A correctly functioning master valve is so important that two master valves are fitted to most Christmas trees. The upper master valve is used on a routine basis, with the low

the main shut-in valve on the well.

the spool or hanger receiver in the wellhead, above which the master valve is the primary control.

upper master valve.

a subsea tree with the master valve above the tubing hanger.