What is the difference between gauge diaphragm seal and other pressure gauges?

When the measured medium is very corrosive (such as hydrochloric acid, wet chlorine, ferric chloride), has a high viscosity (such as latex), easy to crystallize (such as salt water), easy to solidify (such as hot asphalt), there is a solid floating matter (such as sewage), SUS316 stainless steel pipe will also be corroded by hydrochloric acid. The floating matter in asphalt and sewage will quickly block the pressure guide hole of the pressure gauge, and make the meter lose its function. Diaphragm type pressure gauge can solve these problems. People can choose different corrosion-resistant diaphragm materials according to different strong corrosive media to play a role in corrosion protection.