Is there a problem with the inlet valve opening and the return valve closing when heating? How about turning down the reflux valve?

Open the inlet valve and close the return valve during heating period to protect the normal operation of heating equipment.

As an accident valve and an overhaul valve, the water inlet valve usually has only two working states: fully open and fully closed, and cannot be used to adjust the flow. The main valve is not allowed to open under the running water condition, and its function is:

As a backup protection for overspeed of the unit, when the load rejection of the unit coincides with the fault of the governor, the main valve can be quickly closed and the water flow can be cut off under the condition of tap water to prevent the runaway speed of the unit from exceeding the allowable value and avoid the accident from expanding.

Extended data:

As the inlet valve is an important safety equipment of the unit and hydropower station, there should be certain technical requirements for the structure and performance of the inlet valve:

(1) The inlet valve shall be reliable and easy to operate.

(2) The inlet valve should be simple in structure, small in size and light in weight.

(3) The water inlet valve should have superior performance, and a tight water sealing device should be provided to reduce water leakage, so as to facilitate the maintenance of the rear part of the valve.

(4) The structure and strength of the inlet valve and its operating mechanism should meet the operation requirements, and can withstand the water pressure and vibration under various working conditions without excessive deformation. When an accident happens to the unit, it can be stopped quickly under hydrodynamic pressure, and the shutdown time should meet the requirements of the allowable duration of generator escape and the allowable surge pressure value of pressure diversion pipe, generally not exceeding two minutes.

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