I would like to ask how often the pressure gauges in your respective companies are calibrated? How to verify?

It is inspected once a year by an **authorized metrology verification department.

Depending on the actual circumstances, important and critical equipment, pressure vessels, etc. are inspected every six months, while the rest are inspected annually, with inspections carried out by the local metrology bureau

Calibration of on-site pressure gauges: On-site pressure gauges are divided into two main categories – those used in power stations/thermal power plants for boilers, and those used for purposes other than boilers. For pressure gauges used in boilers, a calibration cycle of half a year is **mandatory**； Pressure gauges not intended for use in boilers are further divided into those for special equipment and critical equipment, as well as those for general use. The calibration period for pressure gauges used in special equipment and critical equipment is set at one year, while that for the others is set at two years. The entities responsible for the calibration of pressure gauges are qualified calibration institutions and their certified staff. Our company’s metrology calibration station has completed the necessary setup procedures, and its personnel possess the authority to carry out calibrations; this constitutes self-calibration. During non-stop calibration, we usually replace the gauge to be calibrated with a spare gauge of the same specification, perform the calibration offline, and then reinstall it. During the shutdown for maintenance, all pressure gauges to be inspected are removed (labeled), inspected offline, and then reinstalled.

It is checked once a year by the local metrology bureau, and there is a fee for this service.

The calibration cycle specified in the current regulations for pressure gauge calibration is half a year