Blowout Preventer Landing Assist Tool (BLAT)
The BLAT (Blowout Preventer Landing Assist Tool) is used to assist in landing a BOP (Blowout Preventer) onto a subsea wellhead. The BLAT is threaded onto 6 5/8" drill pipe (FH or XT-57 Threads), which can be modified per customer request. The BLAT is then lowered through the Telescopic Joint (TJ), until the BLAT's Anti-Torque Boss makes contact with the Pup Transition Joint (PTJ). The PTJ is bolted between the TJ and riser. Rotating the drill pipe clockwise (CW) or counterclockwise (CCW) results in the BLAT's load arms extending or retracting. When extended, the load arms make contact with the inner surface of the PTJ, which allows tension to be applied to the drill pipe. Applying more tension to the drill pipe lifts the TJ, PTJ, BLAT, Riser, and BOP. The BLAT has a Safe Working Load of 2,000 kips.
The PTJ consists of a pup joint which has had a 44.5 inch section removed. The upper and lower transition joint assembly, which is 44.5 inches long, is welded into the pup joint where the section was removed. The pup joint, therefore, retains its original length. This BLAT is designed for a riser which has an outer diameter of 21 inches, and an inner diameter of 19 inches. Modifications will have to be made for different riser sizes. .