Bolt-tensioning-pretightened device and assembly formed by bolt-tensioning-pretightened device

Abstract

The invention discloses a bolt-tensioning-pretightened device and an assembly formed by the bolt-tensioning-pretightened device. The bolt-tensioning-pretightened device comprises a supporting seat and a top plate, wherein hydraulic cylinders are arranged between the supporting seat and the top plate, the bottoms of the hydraulic cylinders are fixedly arranged on the supporting seat, the end parts of ejection ends of the hydraulic cylinders are fixedly arranged on the top plate, and the hydraulic cylinders drive the top plate to be far away from or close to the supporting seat; a tension rod which is vertical to the surface of the supporting seat is arranged on the supporting seat, a through hole is formed in the top plate so as to enable the tension rod to pass through, a groove is formed in one end, far away from the supporting seat, of the tension rod, the groove and the tension rod are coaxial, and internal threads which are matched with external threads of a bolt to be tensioned are formed in the sidewall of the groove; a first rotation driving device which is used for driving the tension rod to rotate forwardly or reversely is arranged on the supporting seat, and a second rotation driving device which is used for driving a nut to rotate is arranged at a groove opening of the groove. According to the bolt-tensioning-pretightened device and the assembly formed by the bolt-tensioning-pretightened device, disclosed by the invention, the work efficiency is high, and the condition that the nut is damaged due to excessive wear during nut tightening can be prevented; the pretightening force for a ring flange is relatively balanced, so that the condition that a local pretightening force is too excessive or too inadequate can be avoided.

Description

technical field [0001] The invention relates to the technical field of bolt fastening and disassembly, in particular to a bolt tensioning pretensioning device and components composed of the device. Background technique [0002] The traditional bolt fastening scheme is mainly tightened by manual wrench or electric wrench. The pretightening force of this operation scheme mainly depends on the thread pretightening when the nut and the bolt rotate in the circumferential direction. The nut rotates circumferentially under the action of the wrench. The internal thread drives the external thread of the bolt, and then forces the bolt to be stretched in the axial direction (the bolt is stretched in the axial direction or has a tendency to be stretched), and the stretched bolt shrinks in the circumferential direction to achieve fastening the goal of. During the tightening process, the thread needs to bear a large friction force, which in turn causes excessive thread wear, especially f...

AI Technical Summary

Problems solved by technology

Disclosed as Chinese patent document CN101898299A is a kind of spindle expansion ring connecting bolt synchronous tightening device, although it can stretch 14 bolts at the same time, but it can only tighten the nuts one by one with a wrench when the bolts are tightened, and the working efficiency is relatively high. Low, and using a wrench to tighten one by one, it will inevitably lead to inconsistent tightening degree of each nut. After the bolt is released, the pre-tightening force of each bolt will be directly different. For the flange, due to the pre-tightening force of each bolt in the axial direction If the force is inconsistent, it is easy to cause unbalanced force on the docking plate surface, and then damage bolts, nuts or sealing rings, etc.

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