Peristaltic pump

I have been very lucky today to find a peristaltic (laboratory ?) pump with a rheostat speed control. Must be a bit old as the coupling states "Made in Great Britain". I intend to use it as a suds pump for the mill. Have read various forum threads, but for soluble oil, what sort of rubber / plastic tube would be best, then where would I get about 250mm of 12 to 14mm OD x 2mm wall tube.

Bob

Bob,

Not wishing to put a downer on your idea but I think that this type of pump will not be adequate for what you want to do as even at a high speed? they do not pump volume and they pulse with large time gaps between pulses. In my work we use them on aquatic systems to dose the tank water and they run approx twelve times an hour twenty four hours a day and we change the silicon rubber tubes every few months because they wear out. they pump known quantities of liquid which we use to keep pH and uS levels at set readings.

Martin Perman

Hi Bob,

I researched peristatltic pump tube. Look on this page:

**LINK**

Neil

Can I suggest using an old car fuel pump? Just needs a simple cam or eccentric to drive, regulate the flow with a tap. The things just tick over when not pumping. Have used them for pumping hyd. oil and white spirit so should be ok for cutting oils.

A slightly larger (than lab pump)version is used here to spray lawnwith fertiliser, the tube has about a 1/2" bore, and the pump has a disc with three free to rotate pegs, by restricting the out let, quite a reasonable pressure is reached. I was doing a repair job on a friends Cream Freeze machine(sort of soft creamy icecream), at his shop, a noticed that it uses a peristaltic pump, the bore of the tube would be about 5/8", soft, food grade plastic. The flow from the nozzle is steady, and controled, you got to fill an icecream cone, and stop without drips. Ian S C

What about a 12v submersible (or external) pump as used for camping and caravan water supplies?

Not sure to what extent the cutting oil would attack the plastic. A model railway speed controller would probably give you sufficient control over the rate. Alternatively control the rate by using a bypass back to the tank.

Martin- am very surprised that your pump tubes last such a short time. Would suggest that with the right types of tube and checking that the roller pressure is not excessive the tubes should be lasting years. The long life tubes will be thin - around 1mm thick and a soft grade of silicone rubber. But then there is not much trade in very long life tubes!!!

One of the great advantages is that if you don't need very long life you can use soft plastic tubes on a disposable basis- thousands used in Hospitals every day to pump fluids into people. Ian's comments about ice cream reminded me of one that was in a relative's shop, it used a peristaltic pump which was never replaced in the 7 years it was used.

CRYPTIC PUMP

Another type of pump which would perhaps be the best for suds & swarf was devised by a guy who worked for George the Brakeman and also has a fishy connection but is best knowen backwards. It also is very easy to make at home. Have a shot!

Billy.

Billy,

Every few months should read on average six months, the roller pressure is fixed and the tube is 2mm thick and we pump disolved salts, we also really on the customer keeping the tanks with the dosing solution topped up which means they can run dry which can cause the tube to stick internallly together. The longest a tube has lasted is nine months.

I still think that the use Bob wants to use it for will not be adequate.

Martin P

Hi guys, some of us are missing the point of this particular topic, original question -

what sort of rubber / plastic tube would be best, then where would I get about 250mm of 12 to 14mm OD x 2mm wall tube.

Thanks Bob

If silicone tube would stand up to the coolant, then there's an 8mm ID, 12.7m OD peristaltic tube in this seller's list.

Andy

Hi Billy, long tiome no see.

Silicone rubber tube only lasted a few hours before we threw it out, but then who wants some other bu**ers blood mixed with yours when you are lying there with your sternam in two halves.

As to whether the pump will do the job, only one way to find out!

chriStephens

I suspect the right type of peristaltic pump has a good chance of working. Many Air Conditioning units use such pumps to discharge condensate to the exterior of the building or to drain. Try looking on auction sites for "condensate pump" and you'll see many of these. Aspen are a common make, one of theirs is rated 288 litres per hour against a 4.8m head. This is ~4 litres per minute, which would suit many users coolant demand I would think. I have one of these pumps and intent to try it some time, the only concern I have is that the tube will wear if there is swarf etc in the fluid, so a good inlet filter is required. I would not suggest this for commercial/continuous use, but for hobby use I think its worth a try.

If there is an issue with the delivery flow being uneven, it should be fixable with a small head tank and overflow, this will stabilise the head and is nice and simple. 

Chris

Edited By Jonesthenuke on 16/03/2013 16:25:13