Труборезки наружные

Overview

The automatic spring-fed knives feature of this tool prevents excessive strain from being applied from the rig floor that could cause the knives to burn or break before the cut is completed.

Construction

The tool consists of a top sub, body, guide, knives, spring dog assembly, thrust washer, thrust bearing, preload sleeve, feed ring, main spring, and shear pins.

Spring Dog Assembly

The Spring Dog Assembly is standard equipment on all External Cutters. The Spring Dog Assembly catches square shouldered col-lars or couplings and retains the cut off section after the cut is made. A variety of pipe sizes can be caught by each assembly for each different size of cutter.

Ratchet Pawl Assembly

The Ratchet Pawl Assembly is designed to catch tapered upset integral tool joints. They are also capable of catching square shouldered collars or couplings. Ratchet Pawl Assemblies fit only one particular size of pipe and will be provided upon request. Special Note: Single Pawl Spacer is required when using a Ratchet Pawl Assembly. 

Slip Assembly

This optional assembly is designed to cut and retain pipe with external tool joints. The slips will grip the pipe at any point and retain the cut-off section after making the cut. Slip assemblies will be provided upon request.

Operation

Run the cutter to the desired depth. Apply enough pull load on the work string to pull the spring dog assembly (or ratchet pawl assembly if used) up against a coupling or upset of a tool joint. This will apply load to the thrust bearings, preload ring, and main spring that will shear the pins on the feed ring. This allows the main spring to apply sufficient load on the knives so the cut can be made.