Circulating water pumps for heating are generally single-stage single-suction or single-stage double-suction centrifugal pumps. The water pumps are fully assembled by the pump factory. That is, the water pump, motor and base plate form an integral device, so the installation is relatively simple. Depending on the installation occasion, follow the instructions for the water pump. According to the installation requirements, install it in place.
Debugging
Starting the pump
Trial operation for circulation pump
Before debugging, garbage and debris in the water in the pipeline must be completely removed, including rust chips, welding residue, mud, etc. Otherwise, during operation, large debris will be sucked into the water pump body and damage the impeller and main shaft. Fine dust in the water, especially hard The particles will cause the mechanical seal friction ring to rub and damage the ring. Therefore, the garbage in the water must be strictly removed to make the water clear before it can be put into operation.
Water pumps that use mechanical seals must not be operated when the water is cut off. When correcting the steering, they can only move momentarily. The two smooth friction surfaces of the mechanical seal are lubricated by a water film. Due to the pressure difference at both ends, water will seep during operation and flow out from the small holes under the bearing sleeve. Trace amounts of water droplets will be absorbed when they reach the ground. Evaporation, if continuous dripping is found, it means that the mechanical seal has been rubbed or cracked and must be repaired and replaced with a new mechanical seal.
Before starting the pump, it can only be done when the valve at the outlet end of the pump is closed. When the pump speed reaches the highest value, the valve can be slowly opened until it is fully opened. Before stopping the pump, the valve at the outlet end of the pump must be closed before the pump can be stopped. However, it is not allowed to operate with the pump inlet and outlet pipeline valves closed for a long time.
During the trial operation, the pressure difference between the inlet and outlet of the water pump must be observed and recorded. This static pressure difference plus the dynamic pressure is the lift of the water pump. Since the dynamic pressure is generally small (about 0.2-0.3m), Therefore, the static pressure difference reflected on the pressure gauge can be regarded as the head of the water pump. Since the G-H characteristic curve of the water pump we choose is relatively flat, when the actual lift is higher than the rated lift of the water pump, it means that the system resistance is too large and the flow rate will drop sharply. When this situation is discovered, it is necessary to promptly analyze and find the cause of the piping system. The resistance must be reduced to meet the flow requirements in the system.
