Starting, running and stopping operation steps of chemical centrifugal pump
2. Running the pump -- starting
When the centrifugal pump is started, there is no water in the outlet pipeline of the pump, so there is no pipeline resistance and lifting height resistance. After the pump is started, the pump head is very low, and the flow is very large. At this time, the output of the pump motor (shaft power) is very large (according to the pump performance curve), and it is easy to overload, which will damage the pump motor and circuit. Therefore, the outlet valve should be closed when starting, In order to make the pump run normally.
(1) Close the inlet and outlet pressure (or vacuum) gauge and outlet valve (if there is a bypass pipe, it should also be closed at this time).
(2) During the starting process, always pay attention to the power reading of the prime mover and the vibration of the pump. The vibration number should not exceed 0.06mm, and the measured part is the bearing seat.
(3) Check whether the leakage of shaft seal meets the requirements, and the leakage of sealing medium shall not exceed the following requirements: for mechanical seal, light oil 10 drops / min, heavy oil 5 drops / min; For packing seal, light oil 20 drops / min, heavy oil 10 drops / min.
(4) Start the motor when there is no problem with turning gear; Start the motor (it's better to start the motor first and confirm that the pump steering is correct before starting the formal operation), and then open the inlet and outlet pressure (or vacuum) gauge. When the pump reaches the normal speed and the instrument points out the corresponding pressure, slowly open the outlet valve to adjust to the required working condition.
(5) When the pump outlet pressure and motor current are normal, gradually open the pump outlet valve, and closely monitor the motor current to control the current within the red line, so as to prevent the motor from overload and burning the motor;
(6) Check whether the outlet pressure indication is normal and the lubrication condition is good;
(7) Sealing condition: the mechanical seal shall be free of leakage and heating, and the packing seal shall be in continuous dripping state.
(8) Check whether the cooling system operates normally;
(9) Check whether the vibration value and bearing temperature of the pump are within the allowable range. The vibration value shall comply with ISO 2372 and ISO 3495. The temperature of the bearing should meet the following requirements: for the forced lubrication system, the temperature of the bearing oil should not exceed 28 ℃, and the temperature of the bearing metal should be less than 93 ℃; For oil ring lubricating oil or splash lubricating system, the temperature rise of oil pool shall not exceed 39 ℃.
(10) Pay attention to the outlet flow and pressure of the pump at any time, and judge the blockage of the filter screen according to its change. When the blockage is serious, stop the pump immediately.
(11) Carefully and properly handle the problems in the operation, make detailed records, and cooperate with other posts to do the follow-up work.
