High annulus pressure in old producing wells in offshore Malaysia has become a serious issue when it reaches a limit that breaches a well’s integrity pressure envelope. According to the outlined criteria in the Operator Well Risk Management 3.0 (WRM), the operator will perform lubrication work using heavy brine. This action will temporarily reduce the annulus pressure but soon the annulus pressure will start to build up to the original threshold limit hence rendering lubrication using brine a failure, requiring operator to raise Management of Change (MOC) to keep well flowing with numerous action items needed to be in place while looking for the proper solution.

Currently the usage of epoxy resin technology for leak repairs has become a regular practice in the industry. The idea of squeezing resin to seal off the micro-annulus leaks in well casing cemented annuli has become widely accepted in leak repairs. This integrity barrier entails placing and squeezing special epoxy resin into the annuli, filling up the void inside the sealed annuli and squeezing adequate volume of resin gels into the cement micro annuli. Placement of the resin gels can be difficult to execute due to the micro size path; therefore, high pressure is needed to be applied and maintained during pumping.

Since 2016, the operator has had experiences in treating annulus leaks using lubrication methods and also the current deployment of epoxy resin in filling up voids and micro annulus which has enabled the operator to standardize the method to ensure high success. Surveillance logging data was utilised to determine the source of pressure and to estimate the maximum squeeze pressure to be applied during the treatment. Six wells were pilot tested and treated with this special epoxy resin squeeze, with four wells showing a complete seal while the other two wells have shown gradual pressure build up.

This paper outlines the laboratory verification works on the resin mixtures to adapt to the field application in sealing the leaking annuli and describes all the six pilot tested wells that were carried out in one of offshore fields in Malaysia. The various considerations during the design of the rectification treatments as well as the experiences and lesson learnt during the execution phase are also highlighted.

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