amateurdriller Member
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|  | subsea component from wellhead to rigfloor « Thread Started on Aug 26, 2010, 1:58am » | |
Could any body tell me all the subsea component from wellhead to rig floor and their function? If the water depth is know, how can we space out component's length?
Thanks in advance for ur support!
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laurie Full Member
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|  | Re: subsea component from wellhead to rigfloor « Reply #1 on Aug 26, 2010, 9:13am » | |
[amateurdriller wrote Could any body tell me all the subsea component from wellhead to rig floor and their function? If the water depth is know, how can we space out component's length?]
API RP 16Q gives guidelines and space out method
Also you have to know the exact dimensional data for equipment per below. You also need to know the vessel characteristics for distance from rotary to water line at drilling depth and the stroke of the tensioners usually 50 ft as well as the position of the riser tensioner load ring on the telescopic joint From seabed up 1) Wellhead stickup usually about 10ft for 30" or 27" wellhead 2) 18.875" x 15,000 psi BOP stack & LMRP including riser adapter & lower flex joint Depends on number of BOPs and stack configuration 54 to 60 ft 3) 21" o/d riser joints usually 75ft each number to suit MSL 4) approx 1,000ft below MSL is the riser fill up valve about 20 ft 5) Riser pup joints 5ft to 40 ft use any combination to make up in 5ft incriments to 70 ft 6) Telescopic joint min 60 ft stroke can be 75 ft stroke 7) Flexible joint approx 12 ft 8) Riser to diverter adapter approx 6ft
Note 1) All deepwater subsea risers need buoyancy to counter the riser weight and reduce the drawwork and derrick load. such buoyancy is attached to the riser in depth rated bands every 2000 ft or 2500 ft Note 2) A 10,000 ft x 21 riser has a dry weight of approx 2,130 ton and buoyancy to provide uplift will have 53" or 54" diameter Note 3) Overbalance of mud weight inside the riser against seawater pressure outside also to be considered, as 14.5ppg mud weighs a further 480 ton and correct buoyancy reduces the top tension to be applied to the riser whilst drilling
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amateurdriller Member
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Joined: Apr 2010 Gender: Male  Posts: 8
|  | Re: subsea component from wellhead to rigfloor « Reply #2 on Aug 26, 2010, 9:41am » | |
To Laurie
Thank for ur very clear answer about my question. Just a small thing i am not clear.
18.875" x 15,000 psi BOP stack & LMRP including riser adapter & lower flex joint Depends on number of BOPs and stack configuration 54 to 60 ft .
Did u mean that we can have more than 1 BOP in the same time. Could u tell me in detail?
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laurie Full Member
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|  | Re: subsea component from wellhead to rigfloor « Reply #3 on Aug 26, 2010, 3:15pm » | |
Aug 26, 2010, 9:41am, amateurdriller wrote:To Laurie
Thank for ur very clear answer about my question. Just a small thing i am not clear.
18.875" x 15,000 psi BOP stack & LMRP including riser adapter & lower flex joint Depends on number of BOPs and stack configuration 54 to 60 ft .
Did u mean that we can have more than 1 BOP in the same time. Could u tell me in detail? |
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The Complete BOP stack comprises Two main parts a) The lower Stack b) the Low Marine Riser Package (LMRP)
The lower stack comprises from the bottom up 1) Wellhead connector 30 or 27 inch 2) At least three Pipe rams some times Four or more (fixed or variable bore) 3) One casing shear ram (This will cut larger pipe sizes but dose not completly close the wellbore when activated) 4) A drilling spool (this provides seperation between the upper rams so a tooljoints will allways be free from one of the shear BOP's 5) One Shear Blind ram (This will cut drillpipe and close off the wellbore) 6) One Annular BOP 7) One Male connector 21 inch
The LMRP comprised 1) Female connector 21 inch (funnel down) 2) One Upper Annular BOP 3) One Lower flex joint 4) One riser adapter
Note 1) Sometimes the LMRP comprises two annular BOP's Note 2) All the ram BOP's are rated 15,000 psi and the Annular BOP's are rated 10,000 psi Note 3) The individual BOP height is dependant on BOP type single or double and connection flange type flanged or studded. So once again stack manufactures drawing is required for overall height to build into the riser stack up calculations.
hope all is clear now
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