Gauging nozzles 1 are connected to the measuring chamber from which compressed air is delivered to measuring head 2. The clearance between the gauging nozzles and work 3 depends upon the size of work 3. The variation in air flow depending on this clearance is used to check the size of the work. Simultaneously, the hole in work 3 is checked on the basis of the clearance between measuring plug 4 and the hole.
$3735$SHP,M$