SHUT-IN PROCEDURES – DRILLING OR TRIPPING PHASES
Operators and Contractors differ in their operating practices regarding the open and closed position of valves on the choke manifold during the drilling and/or tripping phase. The choke to be used during well control (normally a remotely operated adjustable choke) should be kept in a closed position during normal operations. The valve immediately upstream of this choke should be open during during normal oper-ations and closed following a shut-in. The outer remotely operated choke line valve adjacent to the BOPs (or all fail-safe choke line valves on sub-sea BOPs) are to be kept in a closed position.
SECONDARY WELL CONTROL
IMMEDIATE ACTIONS IN CASE OF A KICK WHILE DRILLING With a surface BOP stack
• Stop drilling (stop rotation when kelly is used)
• Raise the string to shut-in position (lower kelly cock or Top-drive internal BOP above rotary)
• Stop the pump(s)
• Close the annular preventer and open the remotely operated choke line valve(s)
• Inform Supervisor, Toolpusher and crew members
• Check space out and close the pipe rams; bleed off any pressure between the pipe rams and the annular preventer (if so required) and open the annular preventer
• Record the casing and drill pipe pressures and the pit gain In high pressure wells:
• Close the lower kelly cock or top drive internal BOP, install and test the kill assem-bly, pressure up to the closed-in drill pipe pressure and open the lower kelly cock or top drive internal BOP.
With a sub-sea BOP stack
• Stop drilling (stop rotation when kelly is used)
• Raise the string to the hang-off position (lower kelly cock or Top-drive internal BOP above rotary)
• Stop the pump(s)
• Close the annular preventer and open the upper fail-safe choke line valves
• Inform Supervisor, Toolpusher and crew members
• Check the space out, close the (middle) pipe rams to be used for hanging off and close the ram locks (if so required).
• Hang off the drill string and adjust the heave compensator at mid-stroke
• Bleed off any pressure between the pipe rams and the annular preventer (if so required) and open the annular preventer. Check that the pipe rams are not leaking.
• Record the casing and drill pipe pressures and the pit gain In high pressure wells :
• Close the lower kelly cock or top drive internal BOP, install and test the kill assem-bly, pressure up to the closed-in drill pipe pressure and open the lower kelly cock or top drive internal BOP
Notes
1. Raising the string is only done if time permits; in extreme or critical circumstances this operation should be carried out in as short a period as practically possible.
2. Closing the ram locks is optional on surface stacks. Certain ram locks on sub-sea stacks activate in any position along the piston stroke and are an integral part of the operating system.
3. Ensure that the valve upstream of the choke is closed when monitoring the casing pressure.
4. The drill pipe pressure might be zero if a float valve is present in the string.
SECONDARY WELL CONTROL
IMMEDIATE ACTIONS IN CASE OF A KICK WHILE TRIPPING With a surface BOP stack
• Set slips below a drill pipe tool joint (run in stand if pulling out)
• Install a Full Opening Safety Valve and close it
• Close the annular preventer and open the remotely operated choke line valve(s)
• Inform Supervisor, Toolpusher and crew members
• Check the space out and close the pipe rams; bleed off any pressure between the pipe rams and the annular preventer (if so required) and open the annular preventer
• Make up the kelly or top drive and open the Full Opening Safety Valve
• Record the casing and drill pipe pressures and the trip gain In high pressure wells:
• Close the lower kelly cock or top drive internal BOP, install and test the kill assem-bly, pressure up to the closed-in drill pipe pressure and open the lower kelly cock or top drive internal BOP
With a sub-sea BOP stack
• Set the slips below a drill pipe tool joint (run in stand if pulling out)
• Install the Full Opening Safety Valve and close it
• Close the annular preventer and open the upper fail-safe choke line valves
• Inform Supervisor, Toolpusher and crew members
• Check the space out, close the (middle) pipe rams to be used for hanging off and close the ram locks (if so required)
• Hang off the drill string and adjust the heave compensator at mid-stroke
• Bleed off any pressure between the pipe rams and the annular preventer (if so required) and open the annular preventer. Check that the pipe rams are not leaking.
• Record the casing and drill pipe pressures and the pit gain In high pressure wells:
• Close the lower kelly cock or top drive internal BOP, install and test the kill assem-bly, pressure up to the closed-in drill pipe pressure and open the lower kelly cock or top drive internal BOP
Notes
1. If unable to install the Full Opening Safety Valve due to strong flow:
- with no top drive: consider dropping the string or closing the shear rams (provided there is no tool joint opposite the shear rams)
- with top drive: lower, stab and make up the top drive
2. Closing the ram locks is optional on surface stacks. Certain ram locks on sub-sea stacks activate in any position along the piston stroke and are an integral part of the operating system
3. Ensure that the valve upstream of choke is closed when monitoring the casing pres-sure
4. The drill pipe pressure might be zero if a float valve is present in the string