About valves for industrial steam boilers

The valve is a common part in boiler equipment, and the boiler is inseparable from it, but it is also the most easily overlooked by people. But for special equipment such as steam boilers, a small problem may cause explosions or other dangers. Today we will talk about these valves in steam boilers.

When our boiler manufacturers choose valves for boilers, they are determined by the medium, temperature, pressure, and working conditions used to avoid accidents due to improper use of boilers.

For boilers with different working pressures, there should be separate steam pipes and water supply pipes. If a steam main pipe is used together, an automatic pressure relief device and a safety device to prevent overpressure on the low pressure side must be installed on the higher pressure steam pipe. When the water supply pressure difference does not exceed 20% of the maximum pressure, the boiler can be supplied with water from the main water supply system.

Valves should be installed in convenient locations. On the steam-water shut-off valve and regulating valve of the steam pipeline and water supply pipeline, there should be obvious marks to indicate the direction of gas and water flow and the opening and closing direction of the valve. The arrow indicating the flow direction of the medium on the valve body is consistent with the flow direction, which not only prevents misoperation, but also facilitates use and maintenance.

The feed water shut-off valve should be installed between the boiler (or economizer inlet header) and the feed water check valve, and connected to the feed water check valve.

The main steam valve should be installed near the outlet of the drum or superheater header. Two gate valves shall be installed on each steam pipe connecting the boiler and the steam main pipe, and traps and valves leading to the atmosphere shall be installed between the gate valves, with an inner diameter of >18mm.

Air valves should be installed where the drum, superheater and economizer will likely focus air. When the safety valve on the drum can replace the air valve, the air valve may not be installed.

When the trap is used, its working conditions are changing. Therefore, when selecting the displacement of the trap, according to the heating system, it should be several times larger than the normally calculated condensate displacement, and cannot be selected according to the size of the pipe diameter. For steam boilers with an evaporation capacity of less than 4 tons, an automatic feed water regulator shall be installed, and a device for manual control of feed water shall be installed at the stoker operation site.

The water supply pipe at the inlet of the inseparable economizer shall be equipped with a water supply stop valve and a water supply check valve. The inlet of the separable economizer and the water supply pipe leading to the drum should be equipped with a water supply stop valve and a water supply check valve respectively.