This paper covers the strategies implemented when completing the Shwe gas field in Myanmar. The field, operated by Posco-Daewoo, has been in production since 2013. We present our study and evaluation of the reservoir, integrated completion design, operational challenges, and production performance of the wells.
The project began when Myanmar was subjected to economic sanctions and Myanmar is considered a remote location with quite limited infrastructure, so there were many challenges on the logistics front. The goal of our completion design was to complete the unconsolidated reservoir with either openhole gravel pack (OHGP) or cased hole gravel pack (CHGP), depending on the tendency for water production. The upper completion was designed to optimize gas production. Permanent downhole gauges (PDHG) were installed to monitor the reservoir pressure and temperature.
As part of the development program, eight gas wells and one condensate disposal well were drilled and completed from 2013 to 2015.
Logistics and preparation, key contributors to the success of these installations, were supported from Singapore with a limited transit time to the platform, which meant that turnaround time was closely monitored to meet delivery each time.
The lower completion project in the 9 5/8-in casing consisted of four OHGP wells and four CHGP wells. Screen type and size, and gravel type and size were determined using particle size distribution studies with core samples and software simulation. Findings were then further verified with extensive lab testing.
To achieve minimal skin and damage for the gravel pack (GP) carrier fluid, a nonpolymer fluid was used for CHGP and OHGP. Although a breaker was incorporated into the carrier fluid for OHGP, a filtercake breaker was pumped afterward for maximum cleanup. As for CHGP, the wells were acidized prior to gravel packing. Breakers for the carrier fluid were displaced pre- and post-GP.
For the upper completion, five wells with 7-in production string and three wells with 5.5-in production string were completed. After landing the completion string, a formation isolation valve (FIV) was cycled open, followed by well testing. The subsequent pressure matching we performed confirmed that minimal skin and damage were achieved.
We achieved and exceeded all the objectives set for the campaign in terms of HSE performance, operational efficiency, production rate, and sand-free production.