IOF

Well HeadA wellhead is the component at the surface of an oil or gas

well that provides the structural and pressure-containing interface for the drilling and production equipment

Wellhead is referred to casing head and tubing head.Provide a means of casing suspensionX-mas tree is installed on top of the wellhead.Tubing head in located above the casing headProvides a means of attaching a blowout preventer during

drilling.

Christmas tree

an assembly of valves, spools, and fittings used for an oil well, gas well, water injection well, water disposal well, gas injection well, condensate well and other types of wells

The primary function of a tree is to control the flow, usually oil or gas, out of the well.

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When the well and facilities are ready to produce and receive oil or gas, tree valves are opened and the formation fluids are allowed to go through a flow line

A tree often provides numerous additional functions including chemical injection points,

well intervention means, pressure relief means, monitoring points (such as pressure, temperature, corrosion, erosion, sand detection, flow rate, flow composition

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Note that a tree and wellhead are separate pieces of equipment not to be mistaken as the same piece

The Christmas tree is installed on top of the wellhead

A wellhead is used without a Christmas tree during drilling operations,

ValvesThe two lower valves are called the master valves (upper

and lower respectively). Master valves are normally in the fully open position and are never opened or closed when the well is flowing (except in an emergency) to prevent erosion of the valve sealing surfaces.

The lower master valve will normally be manually operated, while the upper master valve is often hydraulically actuated

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• The right hand valve is often called the flow wing valve or the production wing valve, because it is in the flowpath the hydrocarbons take to production facilities

• The left hand valve is often called the kill wing valve (KWV). It is primarily used for injection of fluids such as corrosion inhibitors or methanol to prevent hydrate formation.

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The valve at the top is called the swab valve and lies in the path used for well interventions like wireline and coiled tubing