Key Technologies for Hydraulic Bushings

Bushing Selection Factors

Hydraulic bushings and hydraulic pumps, hydraulic motors, etc. are all hydraulic parts. The use of bushings is large, there are more types, to choose the right bushing, it is necessary to consider the purpose of its use, different working conditions to choose different models of bushings. The main conditions to be considered in bushing selection are the pressure, speed, pressure-velocity product and load nature that the bushing needs to withstand. In addition, whether the bushing has lubrication, the state of lubrication also determines its use effect and life.

Key Technology for Bushings

1.tightening sleeve taper angle difference must be good national standard with △D1mp-△d3mp, different size section tolerance from +0.018-0.09 is the upper bias requirements tightening sleeve taper angle difference can only be large and not small, that is, the large end must be with contact, cone small end can be a little clearance, taper hole with bad, supporting the spherical roller bearing will form a single row of rollers under stress The operation is not stable, vibration, sound, easy to loosen, bearing life is short, high-precision tightening bush taper angle difference should also be ≤ 0.005, to ensure that the contact area with not less than 90%.

2. tightening bushing outer taper on the inner hole of the radial runout (usually called the wall thickness difference) to high precision, otherwise the rotation axis due to the fair amount of centripetal force, can not bumpy operation, vibration, sound, wall thickness difference is "0" is the ideal form. The national standard rules maximum bearing inner diameter 65 following size section is the bearing specification group clearance maximum 1/2 or so, and C level precision maximum clearance value is very, so the national standard qualified tightening sleeve products used in fine level big load bearing supporting is not.
3. fastening sleeve outer taper surface, inner hole appearance of the straightness to be good, is the shape tolerance to be good, cylindricity accuracy to be good, this national standard does not rule any single cross-sectional size in the tolerance field that is qualified, so that is the formation of outer taper surface appearance straightness control is not strict, especially grinding processing outer taper surface tangential grinding, the blank itself straightness is not good, grinding wheel correction is not good, the appearance of the straightness is very poor, ordinary enterprises and no Contour instrument inspection, so this project in China's fastening sleeve industry products on the problem is very big, seriously affect the accuracy of the matching and supporting the stability, as well as the formation of poor bearing function.

4.The thread locking function of the clamping sleeve supporting bearing is through the locking nut rotation axis to move squeeze the bearing inner sleeve end face makes the clamping sleeve and bearing bore taper tight, to reach the purpose of the bearing fixed on the rotation axis, so the bearing nut and clamping bushing thread fit must be good, to meet the requirements of the national standard of ordinary thread.

Bushing Practical Applications

Can be used in: packaging machinery, textile machinery, mining machinery, metallurgical machinery, printing machinery, tobacco machinery, forging machinery, all kinds of machine tools and interchangeable machinery drive coupling. For example: pulleys, sprockets, gears, propellers, large fans and other kinds of couplings; characteristics: high torque, high precision, easy to install and remove, simple operation, good positioning, reduce the scrap rate of the mating shaft and hub, reusable, do not damage the mating surface, is the most ideal, the most economical choice.

1. Installation: The bushings are lubricated at the factory and can be installed and used directly. When installing, first screw three bolts into the screw hole of the flange of the other piece along the circumference of the evenly distributed, the inner sleeve and outer sleeve will be topped off. Then put the expansion sleeve into the hub hole of the design position, use the force plate to tighten the bolts, tighten the method is each bolt each time only to 1/4 of the rated torque, tighten the order to open the seam as the boundary, left and right cross symmetrical tightening in turn, to ensure that the rated torque value.
2. Disassembly: When disassembling, loosen all the bolts for a few turns. Then screw the bolts into the top loosening sleeve in the disassembled screw holes.
3. Protection: Prevent contamination of the expansion sleeve during installation. In the open air or poor working environment of the machine, the exposed end of the expansion sleeve and the bolt should be regularly coated with rust-proof grease, should choose a better rust-proof expansion sleeve type. The expansion joint sleeve is a new advanced mechanical foundation parts in recent times. Is now widely used internationally to achieve machine parts and shaft coupling, by tightening the high-strength screws so that the pressure and friction between the inclusion surface to achieve load transfer of a new type of keyless coupling device.