Pressure resistance test machines that utilize liquid pressure; Leak testers or leak test apparatus that utilize air pressure; leak testers or leak test apparatus that utilize hydrogen gas; leak testers early test apparatus to utilize helium gas; leak testers early test apparatus that utilize information on flow rate of compressed air; other leak testers were leak test apparatus; pressure gauges; richer sensors; differential pressure sensors; flow gauges; flow sensors; pressure regulators; pressure controller; flow regulators; indicators that indicate pressure, flow, and leakage; and calibrators connected to air leak testers for generating dummy leakage; nozzle diameter measuring instruments that utilize compressed air; and measuring machines and instruments
Electrical and Scientific Apparatus