How to test the NPT screw tooth?

NPT screw tooth thread is commonly used in industry, and how to test the NPT screw tooth? Below small make up to tell you! NPT thread is an American standard taper pipe threads 60 degrees, can be divided into general sealing of cylindrical pipe thread and general sealing tapered pipe thread, cooperate way by & other; Cone/cone & throughout; Cooperate, & other; Column/cone & throughout; To cooperate. Inspection outside the NPT screw teeth, ring gauge used to measure external thread, ring gauge should pay attention to whether the label is still effective when used, should be paid attention to when using, iron filings have adhesion, in order to avoid misjudgement, if the ring gauge when use the iron filings stuck phenomenon, should immediately stop using, and to remove iron. NPT cooperate way: cylindrical internal thread and cone of external thread & other Column/cone & throughout; Cooperate; Of taper thread and taper thread within & other Cone/cone & throughout; To cooperate. NPT threads used in the joint of pressure gauge and bimetallic thermometer, bimetallic thermometer is a kind of measurement in the field of low temperature test instrument. Bimetallic thermometer can be directly measured in the process of various production - 80 ℃ ~ + 500 ℃ within the scope of liquid, steam and gas medium temperature.