pump for slurry, rubber lined vs alloy vs plastic

[slojim]

We have rubber lined pumps in our wastewater system. They handle water with about 25% fine solids. pH is typically ~7, but it seems there may be occasional excursions or variances in the mud bed. The liner life is short (~ 6 months) and the liners are expensive (2-3k, parts only). I suspect there are occasions where it briefly runs dry, I think a thermal shutdown might help on that. I also suspect there are occasionally chunks that pass through, and gouge the liner. This leads to high local wear. I am considering a hard metal of high chrome (worthington) or Cd4MCu (gorman-rupp). The vendors I deal with normally don't have anything in a thermoplastic, so I don't even really know what's out there. I saw Vanton in another thread, but their site is down. Any input? Thanks.

 

[glennpan]

Slojim,

If your slurry is abrasive, plastic pumps may be a very good way to go. Plastic pumps actually have much better resistance to abrasion than lined or even metal pumps. Vanton published an excellent technical article on this topic several years ago that I can forward to you.

What is your flow rate and pressure for this application? How big are the solids that you believe are passing?

Glenn

http://www.panner.com

 

[slojim]

Thanks Glenpan, I would appreciate that article. You can send it to jcesen@mail.utexas.edu.
Flowrate, about 300gpm, head, around 60 to 100ft, size, about like fine sand, but I think we get an occasional damaging chunk, or perhaps even a loose bolt or other trash. They draw on an open top clarifier pond. Once the liner is nicked, it goes quickly.

 

[jet1749]

We use Warman CAH range natural rubber lined pumps . These have proved excellent on water/20% volcanic ash/20% sodium thiocyanate solvent duty. I would think that any pump subjected to loose trash, nuts bolts etc will struggle. Perhaps better to invest some effort in screening out debris.

 

[slojim]

Agreed. As far as the pump is concerned, I'm more concerned about hardened chunks of solids than loose trash. A strainer with small enough mesh to catch them just becomes a place for them to encrust and plug.

 

[jet1749]

A recessed impeller or "vortex" type pump might be worth considering as only around 15-20% of pumpage comes in contact with the impeller. These are rated to pass solids at the size of the pump flange diameter. Trouble is they are low efficiency. My experience with CD4MCu has not been that favourable on abrasive duty, I have only found it to be slightly better that 316SS and a lot more expensive. I have looked at the spec for my own Warman pumps and they are rated to pass solids at 3/8" diameter. However they also service the mining/dredging industies, so they may have alternative pumps.

 

[vdub1963]

Have you considered a high chrome iron? 25-28%Cr - Class III white cast iron. Could double the life or longer? It is very highly abrasive resistant. Especially when it comes to the occasional nut, rocks or bolt!

 

[Jurasic]

Advanced Reinforced Composites are presently used as an alternative method to rubber lining offering dramatically improved life together with perfomance enhancement at an economical cost. Once Composites have been properly applied then repair when worn is only on the actual worn areas not on the complete pump reducing eventual cost of repair and providing long term solutions

 

[slojim]

Is Advanced Reinforced Composites a company? Or do you know a vendor/contact for such a service?

 

[MedicineEng]

Why don't you use a plastic pneumatic pump? It can run dry, it can handle solids up to 1/2" diameter and also also have a quite good chemical resistance. Of course cannot stand with bolts, nuts and stuff like that, but I doubt that any pump can handle this besides that "vortex" type one,that was refered above.
If you are interested,please take a look on this site:

http://www.wildenpump.com/

Hope that helps.

PR

 

[poppeye]

Slojim,
Take a look at a brand named Discflo. They hold up quite well. Quite a few Steel mills are using them to pump their treated chemical waist with little or no maintenance.

Poppeye

 

[poppeye]

Slojim,
You may also want to look into Toyo slurry pumps. They offer fully inclosed and recessed impeller models that are designed for pumping industrial slurry with solids up to 1".
You can E-mail info@toyopumps.com

Poppeye

 

[Roach]

I can vouch for Discflo as a very reputable pump.
They withstand quite a bit of abuse in our facility.

Roach

 

[Jurasic]

Advanced Reinforced Composites is a technology for protecting wearing parts and bringing old equipment back to scratch.
Should you require further info on this subject just ask.

 

[wpilgri]

We manufacture progressing cavity pumps that are quite often used in abrasive slurry applications. The flow are pressure you mention are quite do-able.

 

[nalmeter]

I too have a very similar application. We have stainless pumps that have been running for 15 years and have given us very littlel trouble. In my case I may not have nuts and bolts flying into the impeller, but I do have a Manganese Dioxide powder as well as plastic pellets (and the occasional plastic trash in any wastewater system). We treat this wastewater for pH, hence the pH can swing from 6-9, rarely as low as 4 and sometimes as high as 10 or 11. What material of construction would be most appropriate here since I need to upgrade these pumps? Flow is ~180 GPM @86 FT TDH.

 

[Berko]

Try using a Hidrostal screw centrifugal pump. They will handle the solids indicated & can be be fitted with 27% Chrome Iron liners & Impellers. The liners are also externally adjustable, allowing impeller clearances to be re-set without dismantling the pump.

Have used these in Bentonite slurry pumping + sand laden sewage sludges, tailing dam dredge applications, etc

Good luck,

Berko

 

[sprintcar]

Wastewater with hard or sharp solids can be pumped using hard (white) iron slurry pumps. We had success with GIW in Georgia - email me and I can give you a contact or try their website

http://www.giwindustries.com

Rubber is excellent for your application unless you get sharp objects which tear the liner - then it wears fast. Rubber is also speed sensitive - increased impeller speeds can cause damage.

Keep the wheels on the ground
Bob
showshine@aol.com