Trulok

The inserts are specifically designed components used in a given block in order to align as close as possible the fastener’s shank and head to the center of the set block. They ensure that a certain clearance (.0005 to .0015 inch) exists between the fastener shank diameter and the insert inside diameter. The use of the insert with the set block ensures a better centering and normality of the fastener’s head in the set block at the time of the measurement.

The inserts outer dimensions are different for each block part number in order to avoid accidental usage in other blocks.

The following table (table 1) shows the standard inserts and their dimensions for their respective set blocks. These inserts are used to measure the finished fasteners (including coating). Special insert sizes have been developed for each block in order to measure the head protrusion of the fasteners in different manufacturing stages – see table 2.