XINLI BOILER

Water pressure test procedure for chain grate boiler

30 Dec, 2021

　　(1) The water pressure test should be carried out when the surrounding air temperature is higher than 5℃, and antifreeze measures must be taken when the temperature is lower than 5℃. The water used in the water pressure test procedure for chain grate boiler should be kept at a temperature higher than the surrounding dew point. , To prevent condensation on the surface of the boiler, but it should not be too high to prevent vaporization and excessive temperature stress, generally 20℃-70℃.

　　(2) During the hydraulic test, the inlet water temperature should be kept at about 20°C. If the temperature is too low, dew will be condensed on the outer wall of the boiler, which will be confused with inaccurate conditions such as water seepage, which will increase the difficulty of inspection, and the temperature will be too high. Causes uneven expansion and contraction, and the surface temperature is too high to evaporate the water droplets, making leakage difficult to find.

　　(3) After the water is full, when the pressure is gradually increased to 0.4 MPa, a tightness check shall be carried out. If necessary, the bolts of the flange, manhole door and hand hole cover may be tightened once.

　　(4) During the water pressure test, the water pressure should rise and fall slowly. When the water pressure rises to the working pressure, the pressure rise should be suspended to check for leaks or abnormal phenomena, and then the pressure should be raised to the test pressure and kept for 20 minutes. If the pressure does not drop, it is reduced to the working pressure for inspection.

　　(5) Any leakage should be recorded so that it can be repaired when the pressure drops to atmospheric pressure.

　　The hydraulic test is deemed qualified if it meets the following conditions.

　　(1) There is no water droplets and water mist on the metal walls and welds of the pressure components;

　　(2) After the hydraulic test, there is no visible residual deformation;

　　(3) There is no water leakage in the economizer tube and interface.