Which gauge is used to check the length of the lockbolt pin and diameter of the locking collar?

The swage gauge is specifically designed for checking the length of lockbolt pins and the diameter of locking collars. This gauge is essential in aerospace assembly as it ensures that the fasteners used are within the specified dimensions for proper functionality and structural integrity. The correct measurement of these components is critical; using an inappropriate gauge may lead to improper fitting and potential failure of the assembly.

Other gauges might serve different purposes. For instance, pneumatic gauges are typically used in applications where air pressure measurements are necessary, while digital gauges offer high precision for a variety of measurements. Caliper gauges, while versatile for measuring lengths and diameters, may not be specifically calibrated for the unique requirements of aerospace fasteners like lockbolt pins and collars. Therefore, the swage gauge is the most suitable tool for this particular measurement task.