Centrifugal pump selection and use method and maintenance ②
2. Use of sanitary pump
The trial operation of the sanitary centrifugal pump should meet the following requirements:
① The steering of the driving machine should be the same as that of the pump;
②Find out the steering of pipeline pump and coaxial pump;
③There should be no looseness in each fixed connection part, and the specification and quantity of lubricant added to each lubrication part should meet the requirements of the equipment technical document;
④ The parts with pre-lubrication requirements should be pre-lubricated according to regulations;
⑤All indicating instruments and safety protection devices should be sensitive, accurate and reliable;
⑥ The crank should be flexible and free of abnormal phenomena;
⑦The high temperature pump should be preheated before trial operation, the temperature should rise uniformly, and the hourly temperature rise should not exceed 50℃; the temperature difference between the surface of the pump body and the process pipeline with the working medium inlet should not exceed 40℃;
⑧ Set up a connection device to eliminate the influence of temperature rise, and set up a bypass connection device to provide a cooling water source.
Pay attention to the following points when operating the sanitary negative pressure pump :
①It is forbidden to run without water, do not adjust the suction to reduce the displacement, and it is forbidden to run under too low flow;
②Monitor the operation process, completely prevent the stuffing box from leaking, and use new stuffing when replacing the stuffing box;
③Ensure that the mechanical seal has sufficient flushing water flow, and excessive water flow is prohibited for water-cooled bearings;
④Do not use too much lubricant;
⑤Inspect according to the recommended cycle. Establish operating records, including operating hours, adjustment and replacement of fillers, adding lubricants and other maintenance measures and time. The centrifugal pump suction and discharge pressure, flow rate, input power, temperature of washing liquid and bearing, and vibration should be measured and recorded regularly.
⑥The main engine of the centrifugal pump relies on the atmospheric pressure to pump the water from the low place to the high place, and the atmospheric pressure can only support a water column of about 10.3m at most, so the main engine of the centrifugal pump cannot work 12 meters away from the water surface.