Contact US

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!

*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

Manual 3-way Valve

Manual 3-way Valve

Manual 3-way Valve

I am hoping someone can help me with this. An application calls for a manual 3-way valve where when the lever is in the center, there is no flow to either of the two outlet ports; when lever is turned from center, flow will go through one of the outlet ports (lets call this south); turned the other way from center, flow to the other outlet port (lets call north). The application also wants to know which outlet port is flowing. So let's say we use two (2) position switches where:
  • both contacts open = lever is in center position (i.e. no flow through either outlet port)
  • one of two switches contact is open while other is closed = lever is turned away from center (i.e. flow to south outlet port)
  • other contact open while second contact is closed = lever is turned away from center (i.e. flow to north outlet port)
The problem I see here is leakage if the lever is not perfectly positioned in one of the three positions (center, right, left). Another problem that could occur if the lever is not fully turned to one of the outlet port positions is that the position switch may not activate.

Does anyone have suggestions to prevent these problems from occurring, even if it means I have to go a totally different route?

RE: Manual 3-way Valve

3way valves are not used in modern critical service applications - notorious for leakages. Use 2 separate manual valves instead.

RE: Manual 3-way Valve

I agree with the previous poster, 3 way valves are normally only used where you must ensure there is flow to one or the other branch.
Two single valves will probably be less expensive also.

RE: Manual 3-way Valve

I read that as 3 conditions:
- block
- north
- south
NorthNOT AND SouthNOT = block
I agree with George and Roy, two valves and some logic.

RE: Manual 3-way Valve

Thanks for your replies. Really appreciated. I decided to go with two separate reduced port, trunnion ball valves. Thanks again.

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! Already a Member? Login


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close