×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Positive Displacement Pump Recomendations

Positive Displacement Pump Recomendations

Positive Displacement Pump Recomendations

(OP)
Any thoughts regarding the best type of pump for: Crude oil with a few % solids. The majority of the solids are locked up in an emulsion (roughly 10 to 20%); however some of the large particles (300 microns) are oil wet outside of the emulsion.  The majority of the solids are in the 1 to 10 micron size and are tightly locked up in the emulsion.    

I need a reliable, low shear, positive displacement pump.  Rate would be around 25 gpm at 200 psig.
  
Any suggestions or articles that would help me determine the best type of pump for this service would be appreciated.   
My initial thought is to look into a progressive cavity pump.

RE: Positive Displacement Pump Recomendations

You may want to look at a 2 screw or 3 screw style pump, such as from IMO or Warren.

These units are great for crude oil services, and in fact are used for things like Orimulsion, the bitumen emulsion fuel that was coming out of Venezuela.

In your application, you may want to run aroud 120 rpm, you're probably looking at 5-10 hp, so that's not too big.

RE: Positive Displacement Pump Recomendations

By the way, I dropped a 0, it was supposed to say 1200 rpm.

RE: Positive Displacement Pump Recomendations

I'm starting to see Progressing Cavity Pumps (PCP) mounted horizontally being used in similar applications.  You have to be careful to specify elastomers that are compatible with your fluids, but if you can do that PCP's have a much lower fluid shear than any of the gear or reciprocating pumps which can be important in oil-field fluids.

David

David Simpson, PE
MuleShoe Engineering
www.muleshoe-eng.com
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips Fora.

The harder I work, the luckier I seem

RE: Positive Displacement Pump Recomendations

25 gpm at 200 psi is difficult for a reliable pump on sandy crude oil. Continuous or intermittent duty? You might try a rubber lined gear pump like Bowie Pumps, but the 200 psi may be too high for them.  Worth a phone call though.

RE: Positive Displacement Pump Recomendations

Try this company www.kawa-pump.co.jp They may have sales outside Japan.

RE: Positive Displacement Pump Recomendations

Look at a diaphragm pump.

Ted

RE: Positive Displacement Pump Recomendations

"dickon17 (Mechanical) 24 Nov 07 11:23  
Try this company www.kawa-pump.co.jp They may have sales outside Japan."  

These are commonly called hose-pumps and could prove ideal for your aplication and available from a number of manufacturers.

RE: Positive Displacement Pump Recomendations

Air diaphragm pump is a good choice if there is air source nearby. Be aware it generates pulsations.
Hose pump is the first one I thought, but you'll have to replace the hose a couple of times minumum in a year if the pump is continuous running.
Rotary lobe can also be used for slurry application. The bad point is, you may have to ask the vendor to visit your site if you got problem with the seals or other components. Some maintenance can only be done by the manufacturer.
Progressive cavity does have low shear as indicated by Zdas04. It generates continuous flow. Actually I do not get a reason why you should not use it except for its relatively high cost and large footprint.   

RE: Positive Displacement Pump Recomendations

(OP)
Most diaphragm pumps have high NPSHR similar to reciprocals which rules out that option for my application.  I will stick with my first consideration and use a low speed progressive cavity pump.

Thank you all for your advice.  
CRG

RE: Positive Displacement Pump Recomendations

I have been working with the application of progressive cavity pumps for 10 years and would consider them the best choice for this application.

Low shear, low NPSHr, low pulsation, insensitive to viscosity, easily able to handle the flows/pressures discussed and reasonably tolerant of entrained solids/abrasives (we sometimes use them to pump things like dewatered sewage sludge and chicken carcasses!).

The main point to beware of, as already mentioned will be the selection of the correct elastomer for the stator, especially if the crude is warm or hot.

RE: Positive Displacement Pump Recomendations

Allow me to share some direct experience here... I suggest a reciprocating pump, e.g. Gaso, National Oilwell, Wheatley.  They have been used in this exact service for over 80 years.  Reliable as a rock, operator-friendly, somewhat tolerant of dry running, easy to service in the field, low vibration, low shear.  My experience with this type of pump in this exact service is completely satisfactory.

A progressing cavity will work in this service but be prepared for maintenance hassles.  They do not like to run dry, at all, and they do not like sand despite what anybody says.  Even outfitted with special materials and special clearances, they will see high MTBF.  Oil patch operators tend to have a tough time with these pumps. In my opinion and experience the PC pump is the 2nd choice behind the recip pump.

Same goes for gear pumps.  The solids will eat them alive.  I once retrofitted two Viking pumps with a singe duplex Gaso.  The Vikings were failing about once every two weeks.  The sand destroys the internal clearances.

Hope this helps!

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources