Reinforced Composite Mat, a Proven Solution for Lost Circulation Control in Sumatra Field

摘要

DESCRIPTION: One of Indonesia historic oil producing field in the Sumatera Island is constantly developed in order to maintain production at a sustainable level. The number of wells drilled is between 250 and 400 per year due to the highly depleted nature of the field.One of the main issues that jeopardize the drilling efficiency in this field is the challenge of drilling and cementing under losses; this can result in a poor cement job quality and/or not being able to bring cement up to surface. A bad zonal isolation can cause loss of steam efficientcy, excessive water production and loss of well integrity requiring costly remedial jobs yielding delayed production since the heavy oil reservoir in this area is produced using the enhanced production technique of steam flooding APPLICATION: A solution implemented to cure the losses during the drilling and cementing consists of a newly developed reinforced composite mat fiber and granule based loss circulation solution coupled with a diagnostic computer aided software. The Software validates the efficiency of the pill design in curing the losses while drilling and/or cementing. A total of 50 wells were treated, this technology was used in 48 wells while cementing and 2 wells while drilling with a high success rate. RESULTS OBSERVATIONS AND CONCLUSIONS: This paper will first detail the standard tech- niques that were used historically in order to combat losses while drilling, then will describe the new approach using the reinforced composite mat technology, and shows quantitative results achieved mitigating lost circulation challenges and ensuring competent zonal isolation which led to eliminating remedial work in more than 60% of the wells. SIGNIFICANCE OF SUBJECT MATTER: This innovative approach has increased success rate in bringging cement back to surface during well construction on the first attempt from 2% with conventional techniques to more than 60% using Composite Mat Fiber Technology.