The closing time of annular BOP preventers The main disadvantage of the annular preventer in a drilling rig is the time required to close it. The annular preventer takes three to ten times the fluid volum.
[pdf] Check hydraulic oil on sight level gauge on hydraulic tank, pumps would be making noise if oil level is low. Make sure all hoses are connected properly and not damaged. Check couplings and make sure they are plugged in properly.
[pdf] If the capacity of the air compressor is really too low, check the following: Check differential pressure over oil separator. Replace separator when necessary. Check and replace compressed air filters (if installed). Compressor does not unload. Check if pressure switch is correctly set and working.
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