Труборезки наружные гидравлические

Overview

These quick, smooth operating tools allow for fast recovery of tubing or drill pipe. A hydraulically fed piston forces the knives of this cutter into the pipe to give the operator sensitive cutting control.

Construction

The tool consists of a top sub, segmented piston assembly, knives, knife pins, guide screw, body, and guide. The segmented piston assembly’s feed ring has four interlocking conical piston segments. A heavy-duty rubber ring stretched around the top of the segments firmly holds them in place. A fluid jet hole in each piston segment restricts fluid to provide suffi-cient pump down force against the piston to feed the knives while allowing enough fluid to cool and lubricate the knives during the cut. Each piston assembly is designed for one particular pipe size.

Operation

Begin by assembling the cutter with the proper size piston assembly for the size of the pipe that will be cut. Run the cutter to the desired cutting depth and engage the mud pumps with all lines open. Slowly close the standpipe valve until sufficient pressure forces down the drill string and shears the shear pins. The amount of pressure required depends on the size of cutter and piston assembly being used. Open the standpipe valve to relieve the pressure going downhole. Begin rotating the drill string at 15 to 25 rpm. Gradually close the standpipe valve until sufficient pressure is exerted downhole to feed the piston assembly into the knives to begin making the cut. Avoid pump surges during the cut. Contraction and expansion of the string during the cut will cause the cutter to move up and down the string. This motion will damage the knives. Completion of the cut is signaled by initial rough chattering followed by smooth rotation.

When ordering, please specify:

(1) Name and number of assembly or part (2) Size and type of top connection (3) Name and number of any desired options