27th July 2018
In the event of the wire becoming stuck, the thought of having to drop a cutter can be a stressful one. Closing the wireline valve on the wire, obtaining an effective seal, assembling and deploying the cutter, the cutter reaching depth or activating prematurely is not a routine operation and the feeling of trepidation is something many can relate to. Although the stages of making-the-well-safe are not within its remit, LiMAR® as previous end users, understand the process and therefore have carefully considered each step in the operation of deploying a cutter to address these specific concerns.
The LiMAR Rollerised Rotary Cutter is based on the tried and tested rotating knife concept but with several unique enhancements. The integral and optimised Roller design removes the need for fixing additional roller subs to ensure target depth is reached in highly deviated wells, whilst also ensuring the rope socket on the toolstring to be fished is not passed. This, in conjunction with the premature activation feature, is designed to allow shocks during deployment, which provides the best chance of successfully severing the wire / cable at the rope socket.
The lockable extension tube is a one-piece threadless design for improved strength. By limiting the number of connections, assembly time onto the wire is lessened, limiting exposure under the lubricator and over the wireline valve. Additionally, there are no requirements for fixings such as roll pins or grub screws with the wire-cut retention components and the one-piece extension tube, reducing the number of hand tools required over the well. Compared to the traditional, scalloped design that allows for lateral movement, the new linearly supported rotary cutting mechanism optimises and channels the cutting force, rather than misaligning the cutting action of the rotating knife.