Well Control Emergency Drills: Their Importance and Effectiveness in Risk Reduction
Introduction
Well control is a critical aspect of safe and efficient drilling operations. The ability to manage unexpected events, such as kicks or blowouts, is paramount to safeguarding both personnel and equipment.
Emergency drills play a crucial role in well control by preparing the drilling crews to effectively respond to such situations. Norsok, a recognized standard for the oil and gas industry, emphasizes the importance of regular and realistic well control and emergency drills as a key tool for reducing risk and ensuring a successful response during an actual emergency.
The Importance of Well Control and Emergency Drills
Well control drills are vital in reducing the likelihood of accidents by enhancing the competency of the crew and ensuring the functionality of the equipment. By practicing procedures that are typically non-routine, crews can familiarize themselves with emergency response protocols, improving their ability to handle real-life situations. Regular drills help to ensure that the crew’s skills remain sharp, reducing the chance of human error during critical moments.
Norsok outlines several objectives for well control drills:
- Competence Development: Well control drills ensure rig personnel reach their expected level of competence to perform assigned tasks effectively.
- Skill Maintenance: They allow crews to maintain the required competency levels and be ready to react to emergency situations.
- Demonstration of Competency: Drills allow crews to demonstrate that they possess the necessary skills and knowledge.
- Equipment Verification: They help confirm that rig equipment is in good working order and suitable for well control operations.
- Documentation: Drills serve to document that crews possess the required competencies and that the equipment is fit for purpose.
Types of Emergency Drills
A variety of emergency drills are essential to cover different aspects of well control. Some of the key drills include:
- Pit Drills: These drills train crews to respond to unanticipated changes in pit volume, either a pit gain (influx of formation fluids) or pit loss (overbalance). Regular practice ensures that the crew can quickly respond to prevent further problems, such as wellbore pressure imbalance or kick escalation.
- Trip Pipe Drills: These are designed to prepare crews for reacting to warning signs when the bit is off bottom. They help ensure that crews understand how to handle the situation and avoid the risks associated with tripping pipe.
- Strip Drills: These drills allow crews to practice complicated stripping-into-the-hole procedures, a critical operation when managing wellbore pressure during various stages of drilling.
- Choke Drills: Choke drills provide valuable practice in manipulating the choke during well control operations. Crews that perform choke drills regularly are more skilled at circulating out kicks and controlling influxes efficiently.
- Diverter Drills: Diverter drills are essential in training crews to react when a diverter is required, especially in situations where manual-sequencing diverters are used. These drills ensure that crews understand the correct procedures when dealing with well kicks or pressure issues when a BOP (Blowout Preventer) stack is not yet installed. Regular diverter drills should be performed daily when drilling in conditions where a diverter may be needed.
- BOP Drills: These drills focus on the operation of Blowout Preventers, essential equipment for sealing off the well in case of a kick or blowout.
- On Bottom Drills: On bottom drills prepare crews for well control scenarios that occur when the bit is actively engaged in the formation.
- BHA Drills: BHA (Bottom Hole Assembly) drills focus on the safe handling of BHA components during well control scenarios.
- Out-of-Hole Drills: These drills prepare crews for scenarios when the drill string is removed from the well, testing their readiness to maintain control and respond quickly to emergencies.
- Hang-Off Drills (Subsea): For subsea operations, hang-off drills ensure that crews can handle the well safely while the rig is suspended or “hanging off” the well during critical operations.
Frequency of Emergency Drills
For emergency drills to be truly effective, they must be repeated regularly to ensure crews develop the required competency and can respond effectively to real-life emergencies. According to Norsok, these drills should be repeated often enough to allow crews to demonstrate acceptable levels of competence.
Some key recommendations include:
- Drills should be repeated until crews demonstrate the required competency. This ensures that personnel are ready and able to manage an emergency situation with confidence and expertise.
- Supervisors should alternate the types of drills. This variety helps prevent complacency and ensures that different potential emergency scenarios are addressed.
- BOP drills/function tests should be conducted at least weekly during drilling and tripping operations. This is particularly important because the BOP is one of the most critical pieces of equipment for maintaining control over the well during a kick or blowout.
- Regularly alternating drills helps to maintain competency across a wide range of well control scenarios, improving the overall preparedness of the crew for emergencies.
Conclusion
Well control emergency drills are a cornerstone of safe drilling operations, allowing crews to develop and maintain the necessary skills and knowledge to manage potential well control incidents. By practicing regularly and ensuring that both personnel and equipment are always ready, the risk of an uncontrolled event, such as a blowout, can be significantly reduced. Norsok’s guidelines for the frequency and variety of well control drills help ensure that drilling teams are fully prepared to handle any emergency scenario that may arise. Regular, realistic emergency drills are crucial to maintaining safety and minimizing risk throughout the drilling process.
For more information on Emergency Drills and other Well Control subjects, read my Well Control Manual at: Well Control Manual V2.6 by Edwin Ritchie