Reactivation of Gas Well With Lower Master Valve Problem Using Hottapping Method
Abstract
Lower master valve is the most crucial part of a Christmas tree in a producing well. This valve is directly connected to the well, which means it has direct contact with pressured fluid from reservoir. Therefore, excellent condition for lower master valve is a must.
M-03 is a gas well in M structure Pertamina that had failure in its lower master valve. This well was forced to stop producing due to problem in lower master valve. The disk in the lower master valve was stuck in closed position so that the well couldn’t produce. The problem escalated once the valve’s condition deteriorated. It started leaking gas that made a hazard to the surroundings. For safety reason, an action needed to be taken, however there was no path to kill the well. An alternative solution was needed to solve the problem.
In order to stop gas leak and recover production, hottapping method to make a hole in the lower master valve’s disk was performed. First scaffolding is needed for safety during operation. For this, hoist rotary table was used. Another master valve was added to be the new lower master valve, ignoring the broken original lower master valve. Hottapping assembly was installed above this valve, the rest of the christmas tree was taken down. The drill inside hottapping assembly was moved by air compressor. Once the operation finished, a path for production in the stuck disk was made, christmas tree was reinstalled with one added master valve, flow line was modified, and well was producing again safely (no more gas leak). This solution regained production from well M-03 of 1.5 MMSCFD gas as well as stopping HSSE hazard (gas leak) from the well.
Having this method as a solution provide safety nets if the same problem ever happened at other wells in Pertamina. HSSE problem is something that could not be taken lightly in oil and gas industry. This project served that purpose as well as put the well back into production, which ultimately affected company’s sales revenue.
