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would be closed first, just below a drill pipe tool joint. In this way. the well can be

circulated through the choke-and-kill lines before the blind shear rams are

reopened. The cut section of the drill pipe is in the sealed area between the blind

shear ram and the pipe ram. The sheared end of the drill pipe is open enough to

allow mud from the kill line to enter the drill pipe and be circulated to the surface

through the choke line below the closed pipe ram.

Since the BOPs are the primary means of controlling the well in the event of

a kick, the importance of their proper operation and maintenance cannot be

overemphasized. All rig personnel should be familiarized with BOP operation —

their lives could depend on it.

Thorough testing and maintenance of the BOPs must be conducted on the

surface to ensure a long and dependable operational life subsea. For surface

testing, a test stump carrying the male profile of the wellhead provides a landing
area for the BOP stack. When the hydraulic connector at the bottom of the stack is

latched onto the stump, all seals may be checked for leaks. The following should
be observed when surface-testing the BOP:

Any special diagnostic procedures recommended by the manufacturer for
each component should be conducted.

The control system should be pressure tested before testing the BOP.

All components should be tested at rated working pressure.

Pipe rams and annular preventers should be closed around drill pipe to avoid

damaging the seals.

All hydraulic connections and connectors must be inspected carefully for

leaks in pressure testing the BOP stack with a drill pipe test tool installed in the test

stump, it is advisable to leave the bore of the test tool open to the atmosphere so

leaks may be detected quickly. The open bore also prevents the test tool from

becoming a projectile in the event of thread failure because the test pressure acts

across the effective area of the drill pipe cross section and considerable upward

force is generated.

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