DUST DU Bushing 85*30 90*85*30

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Functions of Guide Bushing (Bushing)

1. Precise linear guidance
Restrict shafts, piston rods or guide pins to reciprocate or rotate along a straight line, control clearance to prevent deflection, skew and jamming, and guarantee motion accuracy of equipment.

2. Load support & lateral force absorption
Bear radial eccentric loads of shafts, avoid direct friction between shafts and housings, disperse impact force and prevent unilateral wear.

3. Wear reduction & self-lubrication
Guide bushings are commonly made of bronze, graphite copper, SF-1 composite bearings, PTFE/POM plastics with low friction coefficient. Oil grooves or porous oil storage structures form an oil film to reduce heat generation and scoring, extending service life of shafts and main components.

4. Isolate hard metal-to-metal contact
The soft wear-resistant bushing acts as an intermediate medium, preventing expensive main parts from abrasion caused by direct steel-on-steel friction.

5. Vibration & noise damping
Buffer motion impact, lower mechanical vibration and running noise, and eliminate crawling or stalling at low speed.

Application-specific functions

1. Hydraulic cylinder guide bushing (for piston rods)

Installed inside the cylinder head to support the piston rod and ensure its linear extension & retraction.
Share lateral loads and avoid uneven wear of oil seals caused by tilted piston rods.
Excessive clearance from worn bushings leads to one-sided stress on oil seals and rapid oil leakage.
Work with dust seals and oil seals to assist dust prevention, lubrication retention and buffer hydraulic shock.

2. Mold guide bushing

Matched with guide pins to control alignment precision of moving and fixed mold halves during closing.
Ensure consistent mold closing position for every cycle, eliminating flash and dimensional deviation of molded products.
High-hardness wear-resistant material withstands frequent opening/closing impact to prolong mold service life.

3. Small motor sliding bushings (powder metallurgy iron-copper bushings)

Support rotating motor shafts; porous material absorbs lubricating oil for long-term maintenance-free operation.
Low-cost compact alternative to ball bearings for small silent motors.

Distinction: Guide Bushing vs Guide Ring

• Guide Bushing (Bushing): Full circular sleeve fully wrapping the shaft, high load capacity & rigid support; used for cylinder heads and mold guide pins.

• Guide Ring: Segmented thin ring for partial support only, low load capacity; mounted on outer circumference of pistons.

Summary

Guide bushing (bushing) is essentially a wear-resistant sliding bearing with four core functions: position motion track, bear loads, reduce friction & wear, and protect main mechanical components. It is an essential wear-resistant support part for all linear and rotary motion mechanisms.