×
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

A bit more about the throat bushing

A bit more about the throat bushing

A bit more about the throat bushing

(OP)
I would like you to explain to me a bit more about the throat bushing features.
How is fixed to the housing? I mean about the tolerances in the outer diameters.
Does The piece is held in position only by effect of the pressure difference between the seal chamber and the rear impeller or need to be fixed due external tolerances with regard to the housing?

What kind of material are usually used?

For a API PLAN 32 with water external fluid and a shaft of 50mm wich would be the appropiate clearance or it depends only on the different pressure?

RE: A bit more about the throat bushing

In the good old days the bush was pressed into the stuffing box by means of interference fit.  the materials can vary depending on application and pump type, ie API or ANSI.  with water you can use Phosphur Bronze and typical clearances API used to be 0.65mm diameteral clearance.  If you have shaft deflection the Phosphur Bronze will not damage the shaft in the event of pick up.  If you are using plan 32 then the tighter the better to keep the solids away but you should consider shaft deflection too.  Other materials that have been used Carbon fixed bush and floating bush design, Hastelloy, Monel etc
   

RE: A bit more about the throat bushing

(OP)
Depending on the housing shape, can you use an stationary part of graphite with O-ring or rubber cup (floating) if the diameter clearance is acceptable? Is there no problems of moving  inwardly of the chamber, or the pressure difference make it not posible?

Which is the usual interference if you use bronze, for instance? because it has to be easy to install, I guess.

RE: A bit more about the throat bushing

do not rely on Oring because over time this will lose interference and come off.  if you have a few thou (0.002")interference that should be fine.  If you have a good lead (chamfer) you can press it in without any difficulty.

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