×
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

Progressive Cavity vs. Screw Pumps

Progressive Cavity vs. Screw Pumps

Progressive Cavity vs. Screw Pumps

(OP)
Can anyone direct me to a site or illustration to help me visually understand the differences between Progressive Cavity and Screw Pumps?  They seem rather similar.  Fundamentally, how are they different?

ChemE, M.E. EIT
"The only constant in life is change." -Bruce Lee

RE: Progressive Cavity vs. Screw Pumps

You can also check pumpuniversity at:

http://www.pumpuniversity.com/

On the start page click on the picture of a "disasemblied" pump and then Look under Moineau pumps for progressive cavity and screw pump for .... well screw pumps

A digest would be:

A progressive cavity allways have a fixed part - the stator - This is the "shell" of the pump and is made of some "soft" material such as rubber viton, bunan or other types of rubber. Then there is a rotor - the moving part - made of steel (or another metal). It look somewhat like a corcsrew. When roattetd inside the stator a pocket (cavity) is "pushed forward" (progressively) thus creating the moving force.

A screw pump, consists of two or more screws. The screws mesh with each other, letting the liquid flow through the pofiles of the screws. The screws are eather both driven by external timing gears, or the idler screw is driven by liquid pressure.

The most common screw pump design is with 3 rotating screws with different profiles. The center screw is driven by an external gear, and the two outer screws are driven by the liquid pressure. The screw helixes provides sealing elements, when the pump rotates. The pump relies on the viscosity of the liquid for sealing and for driving the idler screws.

Best regards

Morten

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