How to improve the pump efficiency

How to improve the pump efficiency

Improve the pipeline system, reduce resistance.Line length should as far as possible, shorten and keep straight, lower velocity in order to reduce frictional head loss;Reducing valve, bottom valve, elbow, the number of orifice plate etc, in order to reduce the local head loss.Reduce the amount of rich water pump outlet pressure, appropriately meet the requirements of pipeline system for the pressure.
Pump is the most widely used general machinery and power consumption, energy consumption and thus improve the efficiency of the pump itself and the pump efficiency to save energy.
Improve the efficiency of the pump itself
1, the blade suction to extension and thinning, which led to earlier liquid by blade, impeller diameter can be reduced with, also can increase the length of the blade passage flow, reduce the relative diffusion;But extends to appropriate, too forward can make into Et area is too small, make the blade inlet fellowship with blade plate wall Angle decrescent, instead of increasing hydraulic friction loss, crowded import port, unfavorable for cavitation and efficiency.
2, between adjacent blade passage is the ratio of export and import area control in 1.0 to 1.3, to reduce the spread loss.If the ratio is greater than l.3, serious flow diffusion and efficiency decline.
3, the greater the hydraulic radius of flow channel, the better, as far as possible make the blade inlet section near the square, in order to reduce friction loss, know by hydraulics, water cross section area and the ratio of wet week called hydraulic radius, namely hydraulic radius a week sectional area/wet water.Wet weeks, in fact is liquid and the surface contact area is large, when the flow channel section from the approximate square becomes long and narrow rectangle, in essence is to make the liquid flow within the narrow section clearance, so must be great resistance.
4, due to the bending diffusion tube hydraulic loss is bigger, now most the slightly bent close to the spread of the straight line segments.For anti-missile leaf, its inlet Angle and position in the circumferential direction, should be combined with fluid flow in a diffuser flow, principle is to form a continuous flow, avoid anti-missile leaves port too narrow entrance section, otherwise the anti-missile blade inlet causes eddy current loss and impact.
5, to the multi-stage pump, the impeller import and prerotation (anti-missile blade outlet Angle less than 90., reduce import relative speed impeller, and at the same time reduce the relative velocity spread, when selecting anti-missile blade outlet Angle less than 90.Before, the flow of water into the impeller produced prewhirl, can.1 indicates a 0.
6, because of the anti-missile blade outlet Angle caused by the prerotation has a great influence on the characteristics of the impeller in the next level, in order to make the theoretical lift when the design formula of Ht – a “lVul U2Vu2” item 1 vul is zero, the missile leaves of outlet Angle should be selected 90., it can eliminate for level at the end of the guide vane rotating components.But experiments show that the efficiency and stability of the performance curve is adverse, especially for some low specific speed pump, in order to obtain the decline curve, anti-missile selection blade outlet Angle should be less than 90., usually in the 60 s.~ 80.The ends of the blades to thin some, lest produce the impact and eddy current losses.
Cross section of blade runner
7, the impeller output width was increased, reducing the impeller outlet absolute speed, so as to reduce the hydraulic losses in the pressurized water chamber.
8, oblique cutting impeller outlet, reducing the length of the line before and after the poor or streamline to select different blade outlet Angle, in order to reduce the plate before and after the flow pressure difference, thus reducing export secondary circumfluence.
9, increase the pressurized water chamber throat area, area of hours when the original design, can make the flow from the block.
(2) reduce the mechanical and friction loss
(1) bearings, packing caused by mechanical friction loss is generally small, little influence on efficiency.Packing seal of mechanical friction loss is bigger than mechanical seal, if can use mechanical seal bei 4 is better.
(2) improve the surface of impeller and guide blade runner.If possible, had better use handheld grinding wheel surface of grinding tools such as the flow path, thus, hydraulic friction loss will be significantly reduced.
(3) before and after impeller cover plate surface and the liquid of disc friction loss, the direct ratio with the impeller diameter 5 times.Select larger blade outlet Angle can reduce the impeller diameter, thereby reducing the disc friction loss.Disk friction loss and surface roughness big relations, impeller cover plate outer wall should be smooth.Reduced q gap between impeller cover plate and guide vane can also reduce the disc friction loss.
(3) to reduce leakage
Appropriate to reduce the gap or lengthen the parts asked sealing gap and the labyrinth seal, etc., increase the leakage resistance, in order to reduce volume loss.
Inside the pump leak occurred in the impeller and the sealing ring, multi-stage pump, axial force balance between devices, etc.
Improve the pump efficiency
Improve the pipeline system, reduce resistance.Line length should as far as possible, shorten and keep straight, lower velocity in order to reduce frictional head loss;Reducing valve, bottom valve, elbow, the number of orifice plate etc, in order to reduce the local head loss.
Reduce the amount of rich water pump outlet pressure, appropriately meet the requirements of pipeline system for the pressure.If a large amount of rich of pump pressure, pump outlet pressure is higher than the system needs to stress, such as the potential need to take down the valve throttling method to buck, power waste.The measures must be taken for water pumps, according to the pressure of system requirements to dismantle a, secondary impeller;If excess pressure is not too big, can take turning impeller approach to stress, make the pump in the system (line) devices work on pump efficiency point as far as possible, avoid under large flow or small flow, efficiency is low.