Detailed Description of Instrument Valve Installation Indicative Specification

valve

(1) Low-pressure valves should be tested under water pressure of 1.25 times nominal pressure to qualify for sealing without leakage.

(2) Valve packing should be inspected one by one and replaced when the packing does not meet the requirements.

(3) Valve type and specification should be checked before installation.

(4) The flow direction of valve medium should be consistent with that of pipeline medium.

(5) Gaskets used in valves connected with flanges shall meet the requirements of pipeline temperature and pressure grades.

(6) The fastening bolt connecting the valve to the flange shall meet the requirements of temperature and pressure grade of the pipeline.

(7) The valve stem of horizontal pipeline should be installed vertically upward, or 45 degrees inclined to the circuit line, or horizontally. The valve stem of riser should be installed in the direction of the circuit line, and the patrol passage should not be affected.

(8) Safety valves shall be rigorously tested one by one and installed vertically. Sufficient cross-section exhaust pipes shall be installed. Pipelines shall be unblocked until safe locations. Drainage pipes shall be installed at the bottom of exhaust pipes.

(9) The safety valve shall be checked by the calibration department before installation.

(10) Under the setting pressure, the safety valve shall be free from leakage and shock.

Meter

(1) Instrument valves and control devices should be inspected and checked before installation, and should reach the accuracy level.

(2) When the medium temperature measured by the local pressure gauge is higher than 60 C, water-holding elbow should be installed before the three-way cock. The inner diameter of the steel water-storing elbow should not be less than l Omm and that of the copper one should not be less than 6mm.

(3) The measurement range and accuracy of pressure gauge must be compatible with the pressure of boiler, and the best measurement range is 2 times the working pressure.

(4) The diameter of the dial is not less than 100 mmo.

(5) When the pressure gauge is put into use, it should wait for the condensate to accumulate and rotate the handle slowly to the normal working position of the pressure gauge to prevent the pressure gauge from being suddenly impacted by the pressure.