Design of sleeve type sliding bolt extractor

This paper designs a sleeve type sliding bolt extractor, which is suitable for working conditions with narrow torsion space or deep depression. It can easily take out 3~10mm sliding bolts, which has simple structure, reliable performance, low cost and good versatility. Features.

Bolt slip is a common problem in mechanical maintenance, including nut slip and thread slip. The main reasons are thread wear, nut corrosion, wrench wear, wrench selection and incorrect force direction. It is difficult to take out the bolt after slipping, which causes great inconvenience to the maintenance work. The commonly used removal methods mainly include “burning”, “rushing”, “welding”, using pipe wrenches or hydraulic clamps. “Burning” increases the matching clearance of the thread pair, which reduces the friction, but may cause local deformation and damage of the machine; “rushing” replaces the slip nut with a V-shaped groove, which is time-consuming and laborious; “welding” replaces slip with iron Nut, but the joint is easy to break; using pipe wrench and hydraulic clamp can be screwed out strongly, but the working space is limited. Up to now, there is no simple and quick way to deal with bolt slippage, especially in the case of narrow screwing space or deep depression. To this end, a slip bolt extractor suitable for use in narrow working conditions or deep recessed conditions is designed, which is of great significance for improving equipment maintenance efficiency.

Structural design

The structure of the slip bolt extractor designed in this paper is mainly shown in the drawing, mainly by the base body 1, the torsion bar 2, the torsion sleeve 3, the pressing handle 4, the friction reducing washer 5, the pressing sleeve 6, the taper sleeve 7 and the sleeve head 8 and the like. Composition. The utility model is characterized in that a through hole is formed in the top of the base body, and the torsion bar is sleeved by a spring, a marble and a torsion bar; the outer part of the base body is designed with a trapezoidal transmission external thread, and the thread pair is connected with the trapezoidal transmission internal thread on the torsion sleeve; at the bottom of the base body The outer side is open, and the inner side of the sleeve is sleeved through the fixing pin; the through hole is opened in the twisting sleeve, and the glove is connected by the spring, the marble and the pressing; the sleeve passes through the outer cone surface and the cone surface is tightly closed. Fitted, and has a hexagonal counterbore (or a four-corner counterbore) at the bottom, and the symmetrical three corners of the hexagonal counterbore have a notch of 0.2 to 0.5 mm according to the size of the nut of the sliding bolt; the friction reducing washer and the pressure The sleeve is mounted in parallel between the torsion sleeve and the sleeve.

2. Working principle

Before twisting the sliding bolt, select the appropriate ferrule and taper sleeve according to the shape and size of the sliding bolt and nut, and twist the pressing handle to ensure that the pressing handle is perpendicular to the base when twisting, so that the twisting sleeve passes the friction reducing washer along the direction of the driving thread. Push the sleeve and the sleeve sleeve to move, so that the hexagonal slotted counterbore at the bottom of the sleeve is compressed by a small amount of compression, giving the sliding bolt a clamping force. Under the action of the clamping force, a 3 to 10 mm sliding bolt is taken out by the torsion and drawing effect.

In order to ensure the normal operation of the device, the ferrule material adopts spring steel with better elasticity and higher hardness; the friction reducing washer adopts copper-tin alloy with low friction coefficient and high hardness; other parts are not easy to be deformed and have high hardness. 45 # steel.

3. Conclusion

The slip bolt extractor designed in this paper adopts the compression method combining the transmission thread pair and the cone friction pair. The nut is clamped before the torsion bolt is twisted, and the pipe wrench and hydraulic pressure can be replaced under the condition that the torsion space is narrow or the recess is deep. The pliers can easily take out the sliding bolts of 3~10mm, and the structure is simple, the performance is reliable, the cost is low, the versatility is good, and the utility model has a large promotion and application value.