PPGI/PPGL(prepainted galvanized steel /prepainted galvalume steel )is also known as pre-coated steel,color coated steel, coil coated steel, color coated steel,pre pianted steel sheet,The PPGI steel coil/sheet made of cold-rolled steel sheet and galvanized steel sheet, subjected to surface pretreatment (degreasing, cleaning, chemical conversion treatment), coated in a continuous manner, and baked and cooled to form a product. Coated steel has light weight, beautiful appearance and good anti-corrosion performance, and can be directly processed.
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Technical Discussion on Maintaining Wet Alarm Valve of Sprinkler System
Wet alarm valve is the central nervous system of automatic sprinkler system, its normal work or not directly affects the normal operation of the entire system, so the daily maintenance of wet alarm valve is very important. 1, should check the rotation of a half moon should be normal, check open the drain valve, the alarm valve flap due to water pressure automatically open, the water flow into the delay after 20-30 seconds, the alarm bell alarm. If the alarm does not sound, should check the entire alarm pipe, remove the scale, sediment and dirt, so that water flow, to prevent alarm failure. If the bell calibration cock is closed, the alarm still sound, you should check the calibration cock is closed, the alarm valve in the annular groove is the accumulation of obstacles, the alarm valve under the rubber is aging or wrinkles. These problems should be promptly ruled out. 2, six months to check the flow of water pressure, check open the drain valve, bell alarm sound, this time, the pressure gauge should not show a significant decrease in pressure, if the decline is more significant, check whether the valve is blocked or not open the largest ; If the pressure gauge shows the pressure drop is obvious, and the alarm does not alarm, should check the wet alarm check valve flap is normal. 3, check the sealing surface of the rubber gasket on the valve disc, remove the dirt and foreign matter attached to the rubber gasket; if worn or damaged, should be promptly replaced. 4, check the seal and valve seat annular groove every year, remove dirt or foreign matter; if damaged, should be replaced by spare parts. 5, according to the water quality of fire water, regularly open the outlet on the filter, clean up dirt. 6, daily attention Fire water level and water pressure and the corresponding valve is in compliance with norms of the state. 7, False alarm handling: Found false alarm, you can check the entire pipeline is leaking, check the delay device overflow hole is blocked or poor drainage. Open the bleed test valve to drain water from the system or check for blockage of the water supply network. Check the wet alarm valve disc assembly and valve seat between the lax seal, so that a large amount of water into the retarder. Check the pipe network in the nozzle for unexpected reasons cause the release mechanism to start. After finding out the reason of the false alarm, it should be promptly handled to ensure that the system is in a good standby state at any time.