Petroleum Zones

Petroleum Zones' Designs

WellHead-XmasTree and Their Components
(Specification: API)

PZ Wellhead&XmasTree

Wellhead & Christmas Tree Assemblies (complete view)

This is the entire class of equipment used to connect tubing and casing to a pipeline or to surface oil-water-gas separation equipment. The wellhead technically is a flanged device that attaches to the casing as the casing stick out above the ground. There are several pieces of equipment that make up a wellhead assembly. These equipment further allow tubing to be placed in the well and the flow of oil & gas to be controlled via chokes at the surface.

The Christmas tree is the term used to describe the entire assembly as it looks vaguely like a Christmas tree in shape. On land, the wellhead equipment look simple. Offshore and underwater, the equipment is very sophisticated and expensive.

A tree cap is sometimes installed on top of each tree above the crown valve to provide quick access to the tubing bore for bottomhole testing, installing a backpressure valve, swabbing, or paraffin scraping. Most tree caps are tapped for a pressure gauge and have internal lift threads to facilitate the installment of the tree.

All valves, connections, tees, and other equipment in the vertical run of the tree must be greater than or equal to the nominal ID of the tubing; however, valves in the wing section are sometimes a smaller size.

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