How to test bimetallic thermometer sheath?

Bimetallic thermometer protecting casing is set outside temperature measuring element, can also be pre-installed in the inconvenience of disassembly device with pressure, resist the measurement medium pressure and corrosion effect, make the bimetallic thermometer and so on instrument can work normally. Bimetallic thermometer case is instrument protection device, instrument and measured dielectric isolation, improve the service life of the instrument, and can run the device case, convenient for instrument for repair and replacement, don't need to stop the machine to replace, the safety of installation workers have very good protection effect. Bimetallic thermometer sheath by threaded connection: at the end of the pipe is in accordance with the provisions of the screw thread standard is processed into external thread, and pipe fittings tight together with internal thread. How to test the bimetallic thermometer sheath? Internal thread specification, external thread specification, material, length, the size shall conform to the requirements of the drawings, appearance ( Visual) No burr, no crack, visible parts have no obvious blemishes. Inspection internal thread specification, external thread specification to use thread gauge, thread gauge is divided into the thread ring gauges and plug gauges. Using plug gauge inspection sheathed internal thread ring gauge or check test sheathed outside thread gauge