HOME > Technical data > Centrifugal pump the points for attention during the operation
Centrifugal pump operation should pay attention to the following points
1.Prohibit no running water, don't adjust the suction population to reduce emissions, banned under low flow rate;
2.To monitor the operation process, completely prevent leakage of stuffing box, the replacement of packing box to use the new packing;
3.To ensure that the mechanical seal are fully rinse of water, water bearing it is prohibited to use too much water;
4.Lubricant don't use too much;
5. According to the recommended inspection cycle.Establish the operation records, including operating hours, packing adjustment and replacement, adding lubricants and other maintenance measures and time.For centrifugal pump suction and discharge pressure, flow, power input, lotion and bearing temperature and vibration should be measured on a regular basis.
6 centrifugal pump host will depend on atmospheric pressure lower pump water to the high place, and atmospheric pressure can support around 10.3 m water column, so the centrifugal pump host 12 meters can't leave the water work.
The maintenance of centrifugal pump
The analysis of the centrifugal pump mechanical seal failure
Centrifugal pump downtime is mainly caused by the failure of mechanical seal.The performance of the failure are leakage, leakage reason has the following kinds:
(1).Of dynamic and static ring sealing surface of the leakage, the reason mainly has: face flatness and roughness do not meet the requirements, or surface scratch;End face between particulate matter, two end can't also run;Installation does not reach the designated position, the way is not correct.
(2).Compensation ring seal leak, the reason mainly has: gland deformation, uneven prestressing force;Installation is not correct;Sealing ring is not in conformity with the quality standards;Seal type selection is not correct.
Actual use effect shows that the sealing component failure most part is dynamic, static ring end face, centrifugal pump seal, static ring end face appear crack is a common failure phenomenon, main reasons are:
(1).Sealing surface when installation clearance is too large, rinses too late to take away the heat generated by the friction pair;Flushing fluid leakage from the seal face clearance, face overheating and damage.
(2).Liquid medium vaporizing expansion, making the two end separately by vaporizing expansion force, when the two seal face hard joint lubrication membrane causing end surface is overheating.
(3).Liquid medium lubricity is poorer, combined with the operating pressure overload, two seal face tracking rotation are not synchronized.Such as high speed pump rotating speed of 20445 r/min, sealing surface center 7 cm diameter, pump running after the linear speed up to 75 m/s, when there is a lag cannot track rotating on sealing surface, instantaneous heat sealing surface damage.
(4).Seal rinses orifice or filter blockage, cause water shortage, make the machine seal failure.
In addition, the sealing surface on the surface of sliding groove, there was a gap joint seal component failure, main reasons are:
(1).Liquid medium is not clean, there are small qualitative hard particles, with a high speed sliding sealing surface, will end surface scratch and failure.
(2).Poor pump drive a coaxial degree, pump open after every turn end was shaking frictional once a week, different heart ring orbit, cause end surface vaporization, overheating of wear and tear.
(3).Liquid medium hydraulic characteristics of frequent cause vibration pump group, sealing surface dislocation caused failure.
Liquid medium corrosion of seal element, stress concentration, hard and soft materials, erosion, auxiliary seal ring 0, v-shaped ring, concave ring and liquid medium are incompatible, the surface damage of the mechanical seal failure deformation, etc, so the damage form to comprehensive analysis, find out root cause, ensure mechanical seal for a long time operation.
(1).Has not been installed pump in the unpainted surface should be coated with a layer of suitable corrosion inhibitor, oil lubricated bearings should be filled with the appropriate oil and grease lubricated bearings should only fill a grease, do not use a mixture of grease.
(2).Short pump clean liquid, washing, suction line, discharge pipe, pump casing and impeller, side by side net pump shell, pump suction line and flushing fluid in the drain line.
(3).Row of net oil bearing box, and then inject clean oil, thoroughly clean the grease and to fill the new grease.
(4).The vacuum seal population and drains, the pump is stored in a clean, dry place, protect the motor winding from damp, with rust and corrosion liquid jet pump inside the shell.
(5).Pump shaft rotation once a month in order to avoid freezing, and lubrication bearing.
Centrifugal pump shut down after the request
(1).The centrifugal pump stop running should be shut down after the population of the valve and pump for pump, in turn, closed again after cooling is attached to valve system.
(2).Heat pump stop shall be governed by the provisions of the equipment technical documents, should be each partial 20 30 min after stop turning, half a circle until the pump body temperature down to 50 ℃.
(3).Low temperature when the pump stop, when no special requirements, the pump should be often filled with liquid.The suction valve and discharge valve should be kept normally open state;Adopt double mechanical seal of pump in low temperature, liquid level controller and sealing liquid pump seal cavity pump grouting pressure shall be maintained.
(4).Transport easily crystallized, easy solidified, easy medium pump such as precipitation, stop the pump to prevent blockage, and immediately with water or other medium flushing pump and pipeline.
(5).Accumulated liquid discharge pump, to prevent corrosion and frost crack.