Use of smooth plug gauge
Smooth plug gauge is used to measure the precision of the workpiece hole size. Smooth plug gauge can be made into maximum limit size and minimum limit size. The end of its minimum limit size is called the through end, and the end of its maximum limit size is called the stop end. The common form of the plug gauge is shown in the figure. There is a cylinder at each end of the plug gauge. When checking the workpiece, the qualified workpiece should be able to pass through the through end but not through the stop end.