TL;DR
A BOP ram seal leak is a well control equipment integrity failure. Pressure test per the regulatory schedule, identify the leaking seal set, and plan a rebuild.
What you might see
- hydraulic fluid loss on BOP closing unit
- wellbore fluid observed at ram preventer bonnet
- BOP failing the pressure integrity test
- closing pressure required rising to maintain position
Likely causes
Ram seal elastomer wear from repeated open and close cycles
H2S or high CO2 exposure degrading the elastomer material
Ram packer damage from an oversized or undersize tubular
Hydraulic operating pressure below the minimum for seal retention
Required tools
- Calibrated BOP test unit
- Hydraulic pressure gauges rated to test pressure
- BOP test plug and test lines
- PPE: H2S respirator, fire-rated coveralls
Safety first
- BOP testing and repair is a well control operation. All BOP work must follow API RP 53 or the applicable regulatory framework and must be performed by well control competent personnel.
- High pressure test fluids used during BOP testing are a high-energy fluid hazard. Maintain exclusion zones during pressure tests.
- H2S and hydrocarbon gas may be present during BOP inspection. Confirm gas levels with a detector before approaching any BOP vent or drain.
Procedure
- 1
Perform a low and high pressure test per the applicable regulatory testing schedule and API RP 53 general guidance.[1]
- 2
Monitor the BOP closing unit fluid level before and after the test. Fluid loss during a pressure hold confirms a leak path.[1]
- 3
Identify which ram function (blind, pipe, shear) is failing the test by testing each function independently.
Warning: BOP testing with wellbore pressure present is a well control operation. Only qualified well control personnel may test or rebuild a BOP on an active well. - 4
Check the hydraulic closing pressure at the function that failed. Low closing pressure reduces the sealing force on the ram packers.
- 5
If ram seal replacement is required, this requires a BOP pull on a drilling rig or a qualified BOP service crew on a production BOP. Do not attempt BOP internal seal replacement without a written procedure and qualified personnel.
- 6
Log all test results in the BOP test record. Regulatory agencies (BSEE or equivalent) require BOP test records.
Sources
Cameron (SLB) Cameron Type U / TL Blowout Preventer (BOP) general technical documentation, Cameron (SLB)
Cameron Type U / TL BOP general ram seal testing and maintenance procedures (general, API RP 53 framework)
More guides for Cameron (SLB) Cameron Type U / TL
How to diagnose annular preventer seal wear on a Cameron Type U / TL BOP
Annular preventer seal wear reduces the BOP closing margin. Track the closing pressure trend and test element condition at each BOP pressure test interval.
How to diagnose hydraulic system contamination on a Cameron Type U / TL BOP closing unit
Contaminated BOP hydraulic fluid causes slow function response and valve sticking. Take a fluid sample, change the filters, and flush the circuit before returning the BOP to service.
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