Creative Solution for Cutting of Blast Joint at High lnclination Wells +/-75 Degrees in Horizontal Wells

Abstract

Recovery of dual completion strings within horizontal wells is almost always a challenging and risky operation. This is generally due to presence of high concentration H2S along with a typically corrosive environment. Also, hard scale within the internal diameter of the completion string accumulated inside the tubing could prevent access to the desired location of a severance operation – which eases the transition of the overall recovery and subsequent work over.

Typically, dual completion horizontal wells contain approximately 200ft or more sections of blast joint above the single packer – essentially across upper perforation. This sort of arrangement and design of completion prevents washing over and leads to excessively long and occasionally complicate fishing operation. This typically involves hard jarring with maximum over pull to retrieve single packer – which can create complications and possible issues with the overall fishing operation. In most cases, the usual option to create the necessary cut to sever the production tubing is via electric line conveyed chemical cutters or radial torch cutters. The deployment of these types of tools offer a more cost effective and faster rig up and rig down – allowing for the required work over to take place is a rapid way. However, due to the typical orientation of these wells, being deviated (+/- 75 degrees) as such – this would prove to be difficult. Also, there often is a significant accumulation of scale inside the diameter of the production tubing which will not allow access to such tools to reach the required cut point.

The general methods, procedures and processes involved in this case were quite novel. The case was studied and came up with creative solution to cut the blast joint at approximately 20ft above single packer at high inclination of approximately 75 degree with a hydraulically actuated through tubing cutter with coil tubing conveyance. The overall project objectives were to minimize the risk of fishing operation, avoid dropped object and avoid the risk of washing over single packer with 4 to 6 joints of wash pipe at high inclination wells which consider weak point with high dog leg severity by conventional fishing tools. The hydraulically actuated through tubing cutter with coil tubing conveyance to cut long string close to the single packer revealed a lot of benefits – primarily in terms of cost and time savings.