Maintenance method of air heater

Hydrostatic test

①Hydraulic test should be done when the air cooler is overhauled or leaked.

②When the circulating water pressure at the zero meter layer of the steam turbine reaches or approaches 0.30 MPa, the hydraulic test face can be fed with circulating water to the water side of the air cooler, and the outlet valve is closed after filling. At this time, the water side maintains the circulating water inlet pressure. Test on the air side. This kind of test can be carried out simultaneously for each group of tube bundles.

③When the circulating water pressure is low at the zero-meter layer of the steam turbine, the hydraulic pressure test face can use the circulating water to enter the water, close the water outlet valve, and then increase the pressure to 0.30MPa with a hand pump to check whether there is air leakage on the air side. This face test is only performed in a single set of tubes.

④Hydraulic test requirements, check that the copper pipe or the copper pipe expansion does not leak or seep on the air side; the joint surfaces on the water side should be tight. If the expansion mouth leaks, water can be filled to make up the expansion; the copper pipe should be replaced if it leaks. Make up the expansion or replace the copper pipe to repeat the water pressure test.

⑤If the number of blocked pipes in a group of loops exceeds 5% of the total number of pipes in the loop, this group of tubes should be replaced.