×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

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

Spacer and Blind
4

Spacer and Blind

Spacer and Blind

(OP)
I am seeking advise on Spacer and Blind aka Paddle blind.

Engineering has advise me it is THROUGH BOLTED and explained it as they are expecting bolt holes drilled all round the circumference ?

Would this be correct from the research I have found for the product to work it would have to fit within the Bolt circle, is that correct.

In brief how does this product configuration operate ?

Also my workshop have submitted drawings to me that show a bolt hole drilled into the TAB part of both products, is this how they connect together just with studs and nuts ? if so though surely the two pieces would be offset from each other once bolted ?

Many thanks

RE: Spacer and Blind

GOS,

Do you have a sketch?

--
JHG

RE: Spacer and Blind

Just look at or search asme b16.48

That will give you all you need.

Through bolted spacers and blinds can be made but that is simply a waste of metal as they do nothing for you but if you want it you can have it.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Spacer and Blind

3
Gos
Regarding
Spacer and Blind:
Question #1
Engineering has advise me it is THROUGH BOLTED and explained it as they are expecting bolt holes drilled all round the circumference?
Answer #1:
"Engineering" has given you wrong information on this issue. The Spacer and the Blind DO NOT come with Bolt holes all around the edge.

Question #2
Would this be correct from the research I have found for the product to work it would have to fit within the Bolt circle, is that correct?
Answer #2:
You are correct!

Question #3
In brief how does this product configuration operate?
Answer #3
At the bottom of this posting I have included a Link (Images of Spacers and Blinds). When you look at the many examples you will see (a) they do not have Bolt Holes all around the outside edge. There is sometimes only one hole in the Connection Tab (of the Figure "8" model) or in the "removal Tab" (Handle) of the individual Spacer or Blind. To Remove or insert a Spacer or Blind you first depressurize the System, Then make it Safe. Then you remove all the Bolts on One (1) side of the Flange set. Then you "Jack" the Flanges apart using the built-In Jack Screws (in the Flanges) or with Flange Spreaders (Look it up). Now with the Flanges spread apart you lift the Blind (or Spacer) out and make the change. Note, The hole found in the handle of the typical Blind or Spacer in not in the location that makes useful for Flange Bolts. That hole is there to provide an attachment point for a hook and chain for lifting during removal and installation.

Question #4
Also my workshop have submitted drawings to me that show a bolt hole drilled into the TAB part of both products, is this how they connect together just with studs and nuts ? if so though surely the two pieces would be offset from each other once bolted ?
Answer #4
NO! That hole in the Tab is NOT for joining of a Blind and Spacer (See answer #3).

Look at this Link for many examples of Spacers and Blinds"
https://www.google.com/search?site=&source=hp&...

Sometimes its possible to do all the right things and still get bad results

RE: Spacer and Blind

Only thing to add to an excellent post by pennpiper is that you can buy spectacle blinds which are designed to have ONE bolt hole permanently engaged ( usually one of the top or side ones, so that once you remove all the other bolts and separate the flanges, you can swing the blind / spacer around with ease and it also give you a very easy way to visually see whether you have a spacer or a blind flange.

They look like this.


Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Spacer and Blind

Would the answer be the same if the flanges were Class 125, full-face and made of cast iron? I would be uncomfortable with a standard paddle blind in that flange. Is there another alternative for this case?

Johnny Pellin

RE: Spacer and Blind

JJPellin,
You ask an interesting question. I do not remember ever having Spec Blinds, Spacers or Figure "8"s in a Class 125 System.
There could have been some there, I just don't remember any.

Lets wait and see if any show up and what was the solution.

Sometimes its possible to do all the right things and still get bad results

RE: Spacer and Blind

If you are going up against a pump or other piece of equipment with a flat faced flange you might need a full-face spacer, especially if it were cast vs forged. I'm reminded of a project where we did this for about 100 20 inch valves but I don't remember the details.

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


Resources

Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

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