Multistage centrifugal pump is two or more than two impeller centrifugal pump, is mainly composed of four parts: the original motivation, impeller, pump shell and the shaft seal device. Multistage centrifugal pump in the working process working principle with common pumps for example, before the start of the pump shell, internal first filled with liquid, after starting the impeller under the drive of the electric motor rotating speed, when the impeller rotates, the impeller inlet water pressure decreased, less than atmospheric pressure, and along the direction of the impeller radius of water pressure rising, far higher than the atmospheric pressure, so that, in the water inlet pipe to form a suction. Outside atmospheric pressure, low water open water inlet valve, along the inlet pipe into the pump housing, was thrown into the water outlet of impeller. Such low water can be continuously pumped uphill. Multistage centrifugal pump in the use of the process should pay attention to the daily maintenance to prolong his life. The following is in routine use of multistage centrifugal pump should be how to maintain some aspects of attention:
In 1, before starting to prepare
In order to ensure the safe operation of multistage centrifugal pump, before starting the machine should make necessary inspection. First hand slow turning shaft coupling or pulley, water pump to observe whether correct, rotation is flexible, smooth, pump there is no impurities, bearing the operation is normal, whether the right belt, check all the screws are solid; check unit next to no hinder operation of the debris; check the water pipes deep enough; a water outlet valve want to close, in order to reduce the load, and pay attention to start immediately after opening the valve.
2, in service inspection
After starting up, should check the various instruments are normal, steady work, current should not exceed the rated value. Pressure gauge pointer should be in the scope of design; check whether the normal pump out the water, check each part of water leakage examination of whether the unit; the packing degree, typically packing should have small leaks ( no more than 10-20 per minute ), the mechanical seal leakage should not be greater than 10ml / h ( about 3 drops per minute ); rolling bearing temperature should not be higher than 75 degrees; sliding bearing temperature should not be higher than 70 degrees. And pay attention to sound, abnormal vibration, pay attention to reduce the amount of water; the timely adjustment of inlet submerged depth; cleaning up trash rack above the floater; through belt transmission, but also pay attention to whether the slipping of belt.
In 3, after shutdown shutdown and matters needing attention
Stop off before the outlet valve to stop, to prevent backflow of water, mechanical damage; each shutdown, should be timely clean the pump body and the pipeline of oil, keep the machine clean appearance, finding out hidden troubles in time; winter downtime, should immediately exhausted water, to prevent frost crack of pump body and interior parts; in the use season ends, should undertake necessary maintenance.
Multistage centrifugal pump 4, periodic inspection
Multistage centrifugal pump periodic inspection can generally be divided into the following three kinds : daily inspection, and use of inspection, as described above; month examination, in under the condition of not dismounting parts, on the equipment surface cleaning and minor repairs, including a pair of bearing temperature, shaft seal leakage and electrical insulation and other aspects of the examination; regular overhaul, including seal oil, check the pump and motor of the case, check the bushing wear, check coupling rubber ring mechanical seal damage, cleaning, cooling liquid filter and pump filter, check the sliding component wear, check the contact liquid components damage, corrosion and other.