The BOP equipment installation shall conform to the following ...
- Wellhead equipment should withstand anticipated pressures and allow for future remedial operations.
- Ram type preventers should be installed the correct way up.
- All connections, valves, fittings, piping, etc., subject to well pressure, must be flanged, clamped or welded and have a minimum working pressure equal to the rated working pressure of the preventers.
- Valves must be of the flush through-bore type when in the open position. Screwed valves and fittings are only acceptable on installations up to 13,800 kPa (2000 psi) WP.
- Always install new and clean ring gaskets. Check for any damage before use. Ring gaskets are not re-usable.
- All correct size bolts/nuts and fittings shall be in place and tight. All connections shall be pressure-tested before drilling is resumed. The use of a torque device for making up bolted connections is recommended.
- The ID of the bell nipple to be installed shall be large enough for slip and seal assemblies to pass through. Slip and seal assemblies shall preferably be landed through the BOPs before lifting the BOP stack.
- When non fluted boll-weevil hangers are used to land the casing string before cementing, wellhead side outlets shall have a bore, large enough to avoid excessive annular pressures whilst cementing. A hydraulically operated valve should be installed in both side outlets to allow closing in the well in an emergency. Note : Fluted hangers are recommended in order to avoid bypassing the wellhead/BOP stack during cementing operations.
- All manually operated valves shall be equipped with hand wheels, and be ready for immediate use, including the valves on the wellhead.
- Ram type preventers on surface BOP stacks shall be installed with extensions and hand wheels connected, and be ready for use.
- BOP equipment shall be function tested and pressure tested, when installed, and at the appropriate times during operations to determine that the system will function properly.
- The Company drilling representative shall inspect and approve every BOP installation after flanging up and testing. He shall witness any BOP pressure test.
- Wellhead side outlets shall not be used for killing purposes, except in case of emergencies.
- Kill lines shall not be used for routine fill-up operations.
- When critical operations are being carried out on high pressure wells, a second kill line should be employed and tied into the kill line near the BOP stack. A high pressure pump should be lined up to this kill line.
- All pipelines shall be securely anchored and fitted with snub lines across the connections.
- Choke lines shall be as straight as practicable and firmly anchored to prevent excessive whip or vibration. Turns, if required, should be targeted. Flexible kill- and choke hoses, longer than 4 m (12 ft), shall be supported and anchored in accordance with manufacturer's recommendations. The distance between anchoring points shall be 4 m (12 ft) or less.
- Ensure the manufacturer's BOP operating manual is followed and no alterations are made to the BOP equipment without written consent from the manufacturer. Re-certification may be required after making equipment alterations.
- Circulating access to the well bore (or annulus) should always be possible, hence one kill/choke line must be connected to the side outlet below the lower most preventer on subsea BOP stacks.
- The kill- and choke lines of a three-ram-cavity BOP stack shall be connected between the lower pipe-and blind/shear rams. The kill and choke lines of a two-ram-cavity BOP stack shall be connected below the bottom ram preventer.
In an emergency situation, the kill line may be connected to the side outlet of the casing spool when circulating access to the well bore is required. The casing spool outlet should have the proper connection to allow changing over the kill line.