This document provides the outline of the minimum requirements for a rig to be accepted for operations on a well location. A rig can be a drilling or work-over rig, snubbing unit, coil-tubing unit, wire-line rig or pulling rig.
GENERAL
1. A detailed rig acceptance procedure shall be included in any Call for Tender and in the rig contract.
2. Prior to the signing of a Well Operations contract or agreement, the Contractor and the Company must have agreed the acceptance criteria.
VITAL RIG EQUIPMENT
1. A rig must be subjected to a comprehensive inspection covering as a minimum its vital equipment which must be found to be in good working condition.
2. Rig Vital Equipment is considered as:
- Rig Power: engines, generators and all associated equipment
- Drawwork: Lifting function, main brake and secondary electric brake or equivalent
- Travelling and crown blocks
- BOP stack including Control System, BOP installation carrier
- Diverter and Diverter Control System when applicable
- Top Drive: all functions
- Mud Pumps – Including supercharging pumps, dampeners and associated safety devices
- Mud mixing system
- Bulk System - including air dryers
- Shale shakers and associated mud treatment equipment
- Conductor tensioning system when applicable
- Cranes
- Jacking system (including jetting system) – Cantilever skidding system or anchor winches depending on the type of unit, when applicable.
CERTIFICATES
1. In addition, the rig owner must provide proof of class (Rig Certificates) maintenance according to inspections by relevant inspecting authorities, proof of insurance and all current certifications and clearances required by local regulations to carry out rig operations.
2. Should the rig contractor’s drill-pipe be utilised for operations, inspection certificates will be inspected for validity together with all BHA subs, cross-overs and pups. Likewise for HWDP. Premium is the lowest acceptable condition.
RIG INSPECTION
1. The rig inspection survey must be carried out by a recognised competent third-party in conjunction with the Well Operations and HSE functions.
2. The findings of the inspection must be prioritised and ranked. Items identified as having significant impact on mechanical integrity or safety of the rig will be classified as ‘critical’. Rig acceptance with outstanding ‘critical’ items will not be allowed unless written dispensation has been given.
3. The Rig Superintendent and Well Operations Manager shall be satisfied that the rig and site areas are as safe as reasonably possible prior to commencing well operations. This shall be recorded on the IADC/API Daily Drilling Report Form.
EQUIPMENT
1. The following minimum equipment shall be present and fully functional:
- Full-opening safety valve and associated required Xovers
- Surface installed inside BOP.
- Gas sensors with alarm on rig floor and BOP area
2. A rig shall be equipped with a trip tank with a level indicator that can easily be read from the driller’s cabin which shall be accurate to a maximum of 0.5 barrels.
3. The minimum mud logging sensors required for drilling operations are:
a. Active pit volume – (all pits in critical wells)
b. Mud weight in/out
c. Total gas (%) at header box
d. Weight on bit
e. Hook-load
f. Rotary speed
g. Standpipe pressure
h. Rate of penetration
i. Pump strokes per minute (SPM)
j. Flow in and out on critical wells
k. Temperature in and out on critical wells.
4. On drilling rigs equipped with a top-drive, one of the Kelly valves shall be remotely operable from the driller’s cabin.
5. A Crown-o-matic or equivalent safety brake shall be installed on the drawwork and be operational at all times whilst drilling and tripping drill-pipe and bottom hole assembly components shall be inspected and graded in accordance with API RP7G specifications. Equipment must be delivered with inspection certificates and checked by the Site Supervisor. Non-destructive testing (NDT) inspection shall also be carried out to an agreed schedule and prior to the commencement of a new contract.
6. All pressure vessels shall be directly fitted with an overpressure relief device.
7. A suitably rated, independently powered fire-fighting pump capable of supporting two fire hoses or one foam branch, shall be provided at the rig-site. An adequate water supply or water reservoir shall also be available.
8. Safety (drench) showers or eyewash stations shall be provided at the rig at: Mud mixing hoppers, Mud pump area, Rig floor, Cement unit and any hazardous chemical mixing or pumping area.
9. The rig shall be fitted with an emergency battery started generator capable of making the well safe and providing the necessary services for well control.
10. If a mud-logging unit is installed it shall have a kick detection system. Note: For drilling the use of a mud-logging unit is mandatory for all operations unless dispensation is obtained
11. Well control equipment shall be as detailed in WOR 16 – Well Control.
12. All rig pressure gauges shall be covered with valid calibration certificates.
13. Hazardous area signals to local regulations or a minimum of API RP 500B shall be available.
14. All electrical equipment shall be certified for any location (hazardous or not) in which it operates.