 Spirol's roll
formed hardened bushing are designed to meet one or more of the
following objectives:
- Align mating
components,
- Eliminate
drilling of a separate bolt hole,
- Protect
bolts from shear loading, and/or
- Maintain
joint integrity
Although
these hollow, lightweight bushings are not precision ground
and do not
require precision holes, thus saving in component and hole preparation
costs, they are capable of precision alignment if the design
guidelines
are followed. Further savings can be achieved by using the inside
of the dowel bushing for the bolt and thus eliminating the
cost
of a separate bolt hole. The design concept also protects the
bolt from shear loads perpendicular to the bolt and isolates
the
forces on the bolt to tension loading. Shear forces acting on
a bolted joint cause the joint members to slip back and forth,
which causes the bolts and nuts to rotate, reducing the pre-load
tension. This is particularly the case with short bolts with
a
reduced clamping distance. |
RoHS compliant 
