The reliability of the production is essential in offshore operations. Producing a well at its maximum rate is important everywhere. This is often compromised by having sand and fines production which not only plugs the wells and reduce production rate but also erode the equipment and settle in surface vessels. This paper describes a case history where an operator was faced with a well that was rate limited because of fines and sand production. An advanced sand control chemistry system was proposed and a treatment was designed. In April 2013, the treatment was performed by bullheading down the production tubing using rate diversion. Extensive engineering was involved in the candidate selection and planning the operational aspects of the treatment. The execution of the treatment was divided into stages – sand clean out, performing step rate test, pre-job modeling and pumping the treatment as per the design. After the treatment, the well was flowed and tested at almost three times the original maximum sand-free rate (MSFR) at an increased choke without sand production. The well has now been flowing for more than a year, at significantly higher rate than the previous MSFR sand free. This paper describes the chemistry of the sand conglomeration, design consideration, execution and the effect on well performance.

While drilling an offshore well in the Gulf of Suez (GoS), Egypt, an operator experienced severe losses of approximately 14,500 bbl of costly oil-based mud (OBM) during the drilling of a 12 1/4-in. hole section through depleted zones. It became obvious that zonal isolation objectives would not be achieved unless equivalent circulating density (ECD) was significantly reduced during cementing to help minimize and control downhole losses. Therefore, a special design of ultralightweight cement slurry combined with epoxy resin was prepared. The goal was to help reduce downhole losses during cementing while enhancing mechanical properties and achieving higher compressive strength of the set cement sheath as per well integrity requirements. This would help prevent formation stress and be helpful during future well construction operations. Epoxy resins are primarily used as secondary barriers to the primary cement sheath, curing tight casing leaks, squeezes, and during well abandonment. Generally literature on resin discusses its resilient mechanical properties, highlighting that the Poisson's ratio of epoxy resin can be closer to that of rubber, while cement is closer to that of glass. It was observed that mixing resin with cement enhances other mechanical properties of cement in addition to enhancing compressive strength. A 9-lbm/gal resin-cement slurry mixture was designed for the discussed treatment, combining 90% cement and 10% epoxy resin. The combined mixture provided all of the necessary properties of the desired cement slurry. The cement treatment was performed as designed and met all zonal isolation objectives. This cement-resin mixture can become a new solution within the industry, replacing conventional cement in many crucial primary cementing applications, particularly replacing ultralightweight high-compressive-strength slurries. This paper highlights the necessary laboratory testing, field execution procedures, and treatment evaluation methods so that this technology can be a key resource for such operations in the future.

Well A, encountered multiple depleted reservoir layers (initial reservoir pressure >10840 psi) with up to 5,000 psi differential pressure across layers due to irregular depletion in thin bedded shale and sand layers. Well was drilled with over 16 ppg mud to limit under balance in any higher pressure layer and overbalance in depleted layers. After drilling 4 lopes of sand body and during the start of drilling the last sand lope, complete loss of circulation was encountered, followed by kick and differential sticking. The original well integrity assurance plan considered the deployment of borehole compensated sonic tool in order to acquire a discriminated cement bond log based on attenuation measurement. Also in the plan, a Cased Hole Dynamic Tester tool was to be run and the selection of pressure points to be based on the results of the cbl-vdl. So to assure the full integrity of the cement and be able to conduct the Cased Hole Dynamic Tester as required and proper decision to be evaluated regarding the Type of GP job, the use of the Ultrasonic Imaging Tool was evaluated to be run under tough and challenging conditions (high mud weight and thick wall thickness). The Ultrasonic tool for cement to casing bond evaluation is typically limited by the attenuation of the ultrasonic echo caused by the wellbore mud weight and composition. With the cooperation between BP PhPc and Schlumberger, and making use of worldwide expertise, the decision was taken to include the Ultrasonic Tool in the cement evaluation suite despite the well conditions. The analysis of the log managed to prove the zonal isolation requirements and be a source of development of best practices that can improve cement evaluation even with the presence of heavy SOBM.