Contributed by: Jamin33
GENERAL KNOWLEDGE IN OIL AND GAS PRODUCTION FIELD:
WELLHEADS – GENERAL APPLICATION
The purpose of a wellhead is to:
• Support the weight of the downhole tubing
• Safely contain the maximum surface pressure to which the well will be exposed.
• Provide a way to control the flow of well fluids.
• Permit access into the well for servicing.
• Provide a way to ‘kill’ the well (close it down) when necessary
A wellhead is normally in two parts:
• The wellhead itself.
• A collection of valves called the Christmas tree
The Wellhead
This is the piece of equipment made up of components that support and seal the downhole tubing at the surface. Downhole tubing consists of the casing strings and the tubing strings.
The wellhead is built up as the well is drilled. First there is the surface casing, then the intermediate casing strings. Lastly, there is the production casing which does down through the oil producing formation. The production tubing strings are then run inside the production casing strings.
The production tubing strings are hung either in tension (stretched) or in compression. This is calculated from the expected well flowing conditions. When the tubing becomes hot it expands and becomes longer.
When the tubing becomes cold, during well stimulation operations, it contracts and becomes shorter. When there is pressure in the tubing it balloons and becomes shorter.
All this movement of the tubing strings has to be compensated for at the design stage of the completion...
***Download selengkapnya di :
www.caaip.net/download/FSO_FPSO_Mooring_System.pdf
***Gambar Mooring System di :
www.caaip.net/download/Mooring_System
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