Knurling is used to enable unrestricted pivoting of the polyurethane bush around the crush tube or any other mating steel surfaces. The knurling has inherent design advantages – reducing the surface area of polyurethane in contact with the crush tube, which results in less frictional force being developed. The design of the Speedy Parts knurl bore combined with the integral grease retention lips, keeps the lubricating grease intact for the life of the bushing, and eliminates the necessity for periodic re-greasing.
Bullet Grooves and Voiding
Bullet grooves are incorporated in the design of Speedy Parts bushes to allow for variances in control arm or spring eyes. The voiding and bullet grooves also allow for the transgression of displaced polyurethane into the volume of the grooves as the loads of normal vehicle operation are applied. Even though polyurethane is in a solid form when it is manufactured into bushes, its unique properties enable it flow in a manner similar to a liquid when loaded. The action of the bush flowing into its voids prevents the generation of noise, vibration and harshness within the bush and its mount.
Tangential Grease Grooves in Head
The tangential grease grooves in the heads of shackle bushes reduce the friction between the head of the bush and the shackle plates. The grooves store grease, which is smeared around the mating surfaces when the spring shackles rotate, forming a lubrication boundary layer. This has the effect of minimising head friction and reducing noise.
|Dimensions||22 × 14 × 12 cm|