World's First Successful Installation Of 7" Single-Trip Multi-Zone Sand Control Technology on High Angle 5 Zones Well in Offshore Malaysia
Authors: Wardi M Sukry Azizi , Ghazali M Haziq M , Mahdzan Abdil Adzeem B Ahmad , Razali Ezuan Hanafi , Bela Sunanda Magna , Bakar M Farris B , Salleh Nurfarah Izwana , Mat Syarifah Suliza W , Daud Mohd Ehsanul Hafizi , Jayadi Agus 
Published: February 2025

Abstract
PETRONAS completed well BA-42 on Field BS in offshore Malaysia by pushing to the limit and deviating from the "norm" in delivering cased hole gravel pack with 7″ Single Trip Multi Zone (STMZ) system. This 7″ STMZ installation represents the first ever successful installation of the technology in high angle 5 zones well with maximum inclination of 85 degrees with gravel pack treatment up to Extension Pack pumping technique.
The STMZ system has been successfully installed in a high angle 5 zones well, offshore Malaysia, eliminating the need for multiple perforation, well bore clean up, and conventional stack pack trips, reducing operation time and risk exposure. However, the BA-42 well brings an additional challenge and risk due to the requirement to complete and treat 5 zones across the maximum inclination of 85 degrees. Intensive discussions and simulations have been made to ensure the operation runs smoothly, and major changes have been made to the design of the positioning tool to incorporate lessons learned from previous jobs.
The installation of 7″ STMZ across 5 zones with a maximum inclination of 85 degrees was successful. All tangibles and service tools were run in the hole and landed in the sump packer. The top packer and isolation packers were set, and a good annular pressure test against the top packer was obtained. The FCS / SSD was opened using the Proprietary Z2-Open Only Shifter in the service tool string, and the opened sleeve was tested to 500 psi through the annulus to check the leak-off and ensure the sleeve was in the open position. The service tool was then moved to open the MCS using Proprietary Z2-Open Only Shifter. The operation continued as per the pumping program, which included reverse friction test, circulation test, injectivity and breakdown test, matrix acidizing, re-injectivity test, circulation test, step rate test, and screen out drill. The job type for each zone varied between gravel pack up to extension pack, where the pumping treatments performed using viscoelastic surfactant (VES) as gravel carrier fluid. The upper completion string was then run in the hole as per the tally and landed successfully. All sleeves were opened via electric wireline and tractor for unloading and production, and since then, no sand has been produced.
STMZ system has always been synonymous with being complex. However, the success of 1st in the world, 7″ STMZ in 85-degree inclination with 5 zones has proven that with excellent planning, proper risk assessment and flawless communication, anything is possible. This success has also highlighted the capability of STMZ technology to significantly reduce the time required for multiple zone sand control installation and HSE exposure, which in turn makes marginal wells profitable and economical.