1.0.1 These regulations apply to the isolation and purging design of measurement and control instruments in chemical plants, including application scope, usage requirements, material selection, piping methods, etc. 1.0.2 Isolation or purging is a method to prevent corrosive, high viscosity, precipitation, vaporization, and condensation process media from entering the instrument or measurement pipeline, protect the instrument, and achieve various measurements. 1.0.3 Isolation and purging are interrelated. Sometimes one measurement method can be replaced by another method. When necessary, the two methods can also be used together. Careful analysis is therefore necessary before selecting a measurement method. 1.0.4 For the measurement of process media with high viscosity that is easy to precipitate, vaporize, and condense, the instrument should be installed nearby. 1.0.5 When implementing these regulations, it should still comply with the relevant national standards.
HG/T 20515-2000 history
2014HG/T 20515-2014 Design code for instrument seal and purge
2000HG/T 20515-2000 Design code for instrument seal and purge