Back-up tong binding clip chucking mechanism for open type power-driven clamp

Abstract

The present invention relates to an open mouth type power tongs of back tongs binding clip fastening mechanism for mounting and dismounting pipe thread. It is mainly composed of main components of back tongs main body, back tongs head cover plate, butterfly jaw plate, outward-curved toothed plate, hub spline, epicyclic gear, core shaft, gear ring, stopper pin and handhold shaft. Said invention also provides their assembly structure and connection relationship, and its fastening performance is good and its working efficiency is high.

Description

technical field [0001] The invention relates to a power tong for loading and unloading pipe threads, in particular to a clamping mechanism for an open-type power tong back tong. Background technique [0002] The clamping mechanism of the existing open-type power tongs and back clamps is that the inner surface roller climbs and clamps. Its main structure is as follows: there are four inner curved slope plates in the cavity contained by the main body of the back tong and the cover plate of the back tong head, the rollers are installed on the jaw plate, and the jaw plate is installed in the square hole of the jaw plate frame. When the jaw plate frame rotates at a certain angle relative to the main body of the back tong, the rollers roll and climb along the inner surface of the slope plate, forming a radial translation of the jaw plate, so that the tooth plate contacts the pipe string, realizes fixing the pipe string, and ensures the normal screw thread of the main tong Operati...

AI Technical Summary

Problems solved by technology

This mechanism still has the following deficiencies: First, the upper and lower inner teeth of the main body of the back tong are set to mesh with the planetary gears, especially the lower inner teeth. Once iron filings or other hard debris enter the meshing pair, the meshing pair will be broken If it is stuck, the pliers head must be disassembled to remove debris; secondly, the upper and lower connecting plates of the planet carrier must rotate at a certain angle relative to the main body of the backup pliers, because the deformation of the relevant stressed parts is not consistent and mechanical impurities enter the relative rotation gap , the relative rotation will be hindered, and the clamping action will fail; the third is that the planetary gear bears the torque transmission of the clamp head. In order to meet the strength requirements, the planetary gear must have sufficient axial size, which not only makes the structure complicated, but also occupies the height space of the tooth plate. , in order to meet the height requirements of the tooth plate, the axial dimension of the back tong head must be increased. This clamping mechanism will not be applicable under the condition that the distance between the clamping joint of the drilling tong, the main tong and the back tong is strictly limited. The height of the tooth plate will make the strength of the tooth plate worse, and the damage to the surface of the pipe string will be increased, which will also make the mechanism unsuitable

[0003] The purpose of the present invention is to overcome the inadequacy of the prior art that the inner curved surface roller climbing and clamping mechanism clamps different pipe diameters and must replace parts, and will also overcome the above-mentioned defects of the invention patent technology with application number: 01101342. A new clamping mechanism for the clamping head of the back-up tong. The mechanism does not have a planetary frame to rotate relative to the main body of the back-up tong. There is no planetary gear in the inner cavity of the back-up tong body to mesh with the internal teeth, and only a gear ring is set on the upper part of the back-up tong body to mesh with the planetary gear. , to drive the butterfly jaw plate to rotate without transmitting the torque of the tong head, so that the back tongs of the power tong can continuously clamp any pipe string size in a wide range of positive and negative directions without replacing any parts. Its structure is simpler and its clamping performance is more reliable.

Images