Many people think that lift from the pump rotor plane, actually the real head is driven water (that is, the water pump after the operation the water drop to the lowest level). That from the rotor plane to move the water have a loss, and the answer is yes, but that’s not the head loss, friction loss, also called resistance loss. Resistance loss and head loss is much smaller.
2, about the suppress pump
Submersible pump is actually suppress bad. Even increase the submersible pump outlet to limit head, a short period of time also suppress: not bad. Because even when the pump is not water but the motor is still in turn. After a long time will burn out the reason why not suppress bad, but the water has not been exercising, rotor temperature rise sharply around the pump to burn out. Axial flow pump has the potential to suppress bad, however, when the head too high, too much water pressure axial flow pump rotor leads to the burning motor stalling.
I’ll give you two to without any bad examples. The 11 of the xx series pump flow control function is designed, the minimum flow rate is a times less than the highest flow. How to achieve it, is not, of course, frequency conversion motor, it’s too expensive. The hampshire is by reducing the outlet of the pump diameter for flow control, which is done by suppress pump, the rarely dare to such a design that suppress bad pump.
As another example, I designed a small pool for my friends. But buy big pump, water warehouse will dry up, how to do, suppress bai. The diameter of PVC tube clip flat, this pump has been running rectified don’t suppress bad.
3, about the high lift pump and low lift pump
High lift pump (motor), too: leaf blade small, pumping unit time is little, but brilliant, head high. It is like hanging a low gear, water tankers run slow (less water unit time), but strong uphill.
Low lift pump (motor), too: blade large, pumping unit time is much, but boring, head low. It is like hanging a top gear, water tankers ran fast (water) per unit time, boring but upgrade.
This is my understanding of the high and low lift pump. How to judge the submersible pump is a high lift or low head? See the flow curve, generally has a flow curve on the water pump package. Although there are empty mark, but the curve is the same. If the fast, with the improvement of lift water reduced curve is steep, it is low head pump, whereas high lift pump.
But don’t have a concrete index of on any account, you can need according to oneself, moderate amplification to purchase pumps. Another judgment method is: the same power of water pump, if zero lift water yield a lot larger than the other a pump, which is low head pump. You pay attention to the low pump lift pump often called pond.
4, lift and power relations
For the pump based on the actual power measured, with the improvement of head, the pump power will reduce moderately. But lower ratio and head is not linear relationship, with head raised to a certain degree, the pump power won’t reduce again. In short: head can enhance or suppress pump energy saving effect.
5, optional pump myth
Many people tend to think in terms of energy flow, the choose and buy smaller power of the pump. (in fact is also called the horse run, and don’t want to give the horse eat grass). I take cerritos PP10000 and gen star MP9500 comparison.
Cerritos PP10000: power 135 w. Lift 4.5 M; Traffic 10 tons/hour.
Gen star MP9500: power 210 w. Lift 6.2 M; Flow 9.3 tons/hour.
You see, a star MP9500 than cerritos PP10000 small water yield, power is larger. Cerritos that is bought. If used his cerritos in high-lift environment, that is equivalent to high gear uphill, flow decreases quickly. Could not reach your design flow. But jin on some fish friend often does not take into account their own head and pipe complexity, just blindly pursue big flow low power pump, the results backfire.
6, the piping design
Try to use a larger PVC pipe, so can reduce the friction of flow in pipe, reducing resistance; If the pump with a pagoda on the head as little of the takeover, try to cut through the upper, equivalent to expand the flow; The line to minimize the elbow, valve, shorten the pipe length.
7, optional pump Suggestions
First to look at the use of their environment, if elbow, valve, pipe is complex, high lift pump should be considered even if the head is not high also, because there is a very complex formula to bend, valve in the line losses are converted into a head. I look at the others as a result, the calculated in the management of the complex design much relaxed and piping design for an additional lift.
If there is a drip, there is no doubt that should choose high lift pump;
If it is at the bottom of the filter, there is no doubt that should choose high lift pump;
If the line is complex, and the more curved, should choose high lift pump;
Also is the appropriate pump selected points, even if the traffic is beyond your expectations, you can also suppress the pump.
