Pivot points with low-speed motion, high loading, and, especially, high impact, are often an issue for operators, service technicians, and the design engineer. Unprotected, hydraulic cylinder ends — and the machine or attachment bores they are fixed to — will succumb to wear and can ultimately become out-of-round bores. Specifying a tension bushing into the assembly, however, can alleviate this issue.

Tension bushings are replaceable pivot bearings designed to prevent cylinder ends and associated bores from becoming oval. And unlike soft steel bushings, they can be replaced easily.

Tension bushings, offered by Vogelsang Fastener Solutions Inc., Lakewood, N.J., are split cylindrical bushings made of AISI 1074 or 6150 steel that is through-hardened to RC 45 to 50. The material is noted for its high elasticity and wear resistance. The split can be wavy or straight, depending on the preference of the user. Standard sizes range from 3⁄4 to 3 1⁄2-in. OD, with a 1⁄2 to 3 1⁄2-in. axial length.

The bushings have a relaxed OD that is larger than the cavity into which it will be inserted. They also have chamfered ends to facilitate insertion and removal. The interference fit reduces the width of the split as the bushing is pressed into the cavity

The bushings are self-retaining, and the inherent elasticity of the material provides constant radial tension for a tight fit — even if the bore becomes enlarged. Although they can accommodate high load at low speed, they can also be a cost-effective replacement for bronze bearings, which typically support lighter loads.

For more information, call Vogelsang Fastener Solutions Inc. at (732) 364-0444 or click here.