Type selection of diaphragm pressure gauge

The selection of diaphragm pressure gauges must meet the requirements of process production. For example, whether remote automatic recording or alarm; by nature side medium (such as the temperature of the measured medium height, viscosity, corrosive, flammable and explosive, dirt etc.) whether to put forward special requirements on the instrumentation, on-site environmental conditions (such as temperature, humidity, magnetic field strength and the vibration of the instrument) type etc.. Therefore, according to the requirements of the process, the correct selection of instrument type is an important prerequisite to ensure the normal operation of the instrument and safety in production.       

For example, the common diaphragm spring pressure gauge tube with copper alloy (the alloy steel, high pressure) and diaphragm pressure spring tube material with ammonia are made of carbon steel (or stainless steel), with copper alloy is not allowed. Since ammonia produces chemical reactions with copper, it will explode, so ordinary pressure gauges cannot be used for ammonia pressure measurements.

Diaphragm pressure gauge and ordinary pressure gauge in the structure and material can be exactly the same, but oxygen pressure gauge must be banned. Because the oil into the oxygen system, easy to cause explosion. When the oxygen pressure gauge is used, the oil can not be used as the working medium as the ordinary pressure gauge, and the oxygen pressure meter shall avoid the oil pollution in the storage. If you have to use the existing oil pressure gauge to measure the oxygen pressure, you must wash it with carbon tetrachloride before use, and check it carefully until the oil free.