Peristaltic pumps 2

[coku]

What can I expect for accuracy of delivered volume? Use Pebax 4MM OD, 2.8ID

 

[DesignerMike]

Product viscosity, discharge pressure, suction conditions, age of the hose, and pump speed will all play a significant roll.

A water-like product with the tank above the pump, producing 5 psi discharge with new hose running around the middle of speed curve should be quite consistent.

A 5000 Cps product, 5ft below the pump, running at full speed with 40 psi discharge is a different story.

 

[coku]

Thanks. That's the situation. pressure at output is 1-8 bar, the inputs/outputs same level (height), Viscosity range is 1-20 MPs.

 

[DesignerMike]

20 MPs should be no problem (if that is mili-poise I think)

8 bar is pretty high for many peristaltics (depending on design). Most of the pumps I work with are rated less than 3 bar for this size pump.

If the output pressure stays consistent, you should have good repeatability. Hose life at higher pressures will be the downfall. You will probably want to replace them regularily.

 

[bulkhandling]

Peristaltic pumps are often used as metering pumps, especially in mining industries as I know.
An investigation we did shows that the repeatability of flowrate is not very satisfactory. After a period of use, the hose will not bounce back to the original shape, so it is necessory to re-calibrate it or replace the hose before it blows off if you require certain accuracy. Try talk to the vendor for the accuracy you want.

 

[DesignerMike]

You really have to define your "accuracy" requirements. For some people +/- 5% is close enough....other people are looking at .05%

Do you have a pump that can do 8 bar with this hose?

 

[coku]

I'd like 0.5% accuracy.And the tube is a disposible. 1 day life use.

 

[automatic2]

1 day life sounds short, but will depend on your duty cycle, or more specifically, the percent consumption on the hose qualities. Repeatability is a function of the hoses' life span, and consistency of media being transported. If your hose material selection is appropriate, and your selected pump is capable of loads and speed regulation, your accuracies should be very tight.