The maintenance method of the air heater is as follows:
(1) in unit overhaul or repair, to clean the water side and air side visual inspection. Generally in operation, if the water side is blocked by the water side, the air temperature is 5 centigrade higher than that of the normal temperature.
(2) cleaning and checking at the time of the gun repair
(1) disassemble the circular water inlet, the outlet valve flange screw, and remove the connecting pipe of the inlet and outlet valves.
Remove the front and rear water chamber combined with the face screw, take the front and back water chamber.
Clean the steel tube. Protect the pipe mouth when cleaning.
Rust and dirt cleaning the indoor water, rinse with water.
Use the scraper to scrape the surface of the water chamber and the cooling water and the residue of the flange gasket for the exit.
Check the air side of the tube and the heat sink is damaged.
Check the water chamber there is no crack, no damage of glass partition.
The mount with gasket. The gasket is 3-5mm like rubber pad.
With kerosene brushing bolts, dry coated graphite powder oil.
10 the water chamber inside, import pipe plate is coated with anti rust paint.
11 check the air cooler tube and close windtight walls and seams.
(3) water pressure test
(1) the water pressure test should be done when the air cooler is overhauled or has leakage.
(2) when the circulating water is at or near 0.30MPa of the zero meter pressure of the steam turbine, the water pressure test face can be circulated into the water side of the air cooler, and the water outlet will be closed after filling. At this time, the inlet side pressure of the circulating water should be kept and the air side should be detected. This test can be carried out at the same time.
(3) when the circulating water is low in the zero meter level of the steam turbine, the water pressure test face can use the circulating water to enter the water outlet, then close the outlet valve, then press the manual pressure pump to 0.30MPa to check whether there is air leakage in the air side. The test face is only carried out in a single bundle of tubes.
(4) water pressure test requires that the air side check copper pipe or copper tube expansion mouth not leak water, no water seepage, and the water side of the side should be tight. If the leakage of water can be filled with water, the leakage of the copper pipe should be replaced. Water pressure test should be redone to fill or replace the copper tube.
The number of a group of loop plugging pipes is more than 5% of the total number of the loop, and the tube bundle should be replaced.