Pressure gauge fittings are generally external thread pressure gauge fittings, but can also be internal thread pressure gauge fittings. Pressure gauge fittings are connectors used to connect equipment or pipelines measuring the medium to pressure gauges.
Type of pressure gauge fittings
There are welded tube pressure gauge fittings, expansion tube pressure gauge fittings, T-shaped intermediate pressure gauge fittings, bend intermediate pressure gauge fittings, straight intermediate pressure gauge fittings, conical tube pressure gauge fittings, pressure gauge straight-through fittings, sleeve tube pressure gauge fittings, etc.
Standard sizes of pressure gauge fittings
There are standard sizes for pressure gauge fittings in each country. The international standard pressure gauge fitting and the European and American standard pressure gauge fittings generally use the metric thread pressure gauge fittings. The British and American countries generally use the G thread pressure gauge fittings and the NPT thread pressure gauge fittings respectively.
The metric thread notation for pressure gauge fittings: M20X1.5, M14X1.5, M10X1;
The British thread notation for pressure gauge fittings: G and ZG commonly used standard configurations G1/2, G1/4, G3/8, G3/4;
The American thread notation for pressure gauge fittings: NPT commonly used standard configurations 1/2 NPT, 1/4 NPT;
Explanation of pressure gauge fitting threads
Metric: M20X1.5, flat sealing thread, 20 indicates the diameter of the thread at the connecting part is 20mm; 1.5 indicates the distance between the tooth peaks of the thread is 1.5mm; M indicates a 60° flat sealing thread with a sharp tooth angle.
British: G1/2inch flat sealing thread; ZG1/2inch (R1/2inch) self-sealing conical tube thread; G indicates a 55° flat sealing thread with a sharp tooth angle; ZG indicates a 55° self-sealing conical tube thread; 1/2 indicates the diameter of the connecting pipeline, usually with: G1/2 inch.
American: 1/2inch NPT self-sealing conical tube thread, "NPT" indicates a 60° self-sealing conical tube thread.
Instructions for using pressure gauge fitting threads
The M20X1.5, G1/2, ZG1/2 (R1/2inch), and 1/2inch NPT threads are generally used for the Y-100/Y-150 pressure gauges; and the M14X1.5, M10X1, G1/8 inch, G3/4 inch, G3/8 inch, and 1/4 NPT threads are used for the Y-60/50/40 pressure gauges.
Commonly used pressure gauge fitting threads
Pressure gauge fittings metric thread: M14X1.5, M20X1.5;
Pressure gauge fittings British thread: ZG1/4inch, ZG3/8inch, ZG1/2inch, G1/4inch, G3/8inch, G1/2inch;
Pressure gauge fittings American thread: 1/4 NPT, 1/2 NPT, 3/8 NPT.
Pressure gauge fitting materials
Copper or carbon steel pressure gauge fittings: used for normal medium pressure measurement systems or for pressure measurement with ammonia;
Stainless steel pressure gauge fittings: materials such as 304SS, 316SS, 316L, titanium, tantalum, Monel are used for pressure measurement with corrosive media.