×
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

Flange 4" 150 RF Blind c/w 2" NPT Center Tap A105 N

Flange 4" 150 RF Blind c/w 2" NPT Center Tap A105 N

Flange 4" 150 RF Blind c/w 2" NPT Center Tap A105 N

(OP)
Hello everybody,
Can anyone please send me a photo were the flange with the given description is shown?
Flange 4" 150 RF Blind c/w 2" NPT Center Tap A105 N
Any help is appreciated.
Thank you.

RE: Flange 4" 150 RF Blind c/w 2" NPT Center Tap A105 N

I'd think it would be for an instrument connection, something like this, but the "1/" seems to be missing before the "2", ie. as "1/2 inch".
Unless you have a very, very large diameter and very, very thick flange.

RE: Flange 4" 150 RF Blind c/w 2" NPT Center Tap A105 N

(OP)
Dear BIgInch
Thank You for your reply.
Can you please explain why that use the word blind and after that NPT center tap?
Am I missing something?
Thank you.

RE: Flange 4" 150 RF Blind c/w 2" NPT Center Tap A105 N

Sorry! I missed the blind. Guess we know who's blind today.

In that case it is not the above at all. The tap is through the blind flange's thickness, right in the center of the flange. Right in the middle of the "O"
In which case a 2" probably fits.

RE: Flange 4" 150 RF Blind c/w 2" NPT Center Tap A105 N

(OP)
Thank You for your help BigInch.
Regards.

RE: Flange 4" 150 RF Blind c/w 2" NPT Center Tap A105 N

Would think that it would look something like this:



RE: Flange 4" 150 RF Blind c/w 2" NPT Center Tap A105 N

(OP)
Thank You for your answer Bimr.
Regards

RE: Flange 4" 150 RF Blind c/w 2" NPT Center Tap A105 N

Wouldn't that be a 2" thread-on flange

RE: Flange 4" 150 RF Blind c/w 2" NPT Center Tap A105 N

As opposed to a 2" tap in a 4" blind flange

RE: Flange 4" 150 RF Blind c/w 2" NPT Center Tap A105 N

Friends, the description in the question is misleading.

Making 2" NPT thread on 4" Blind flange is prohibited by ASME B16.5 (regardless to flange class)
Please see in Table 6 for reducing flanges, at columns 3+4: the smallest size of reducing outlet requiring Hub Flange for NPS 4" is 1.1/2"

As you all very well know, Blind Type Flange IS NOT Hub Flange, so, 2" outlet on 4" Blind is prohibited.

What you need here is: Threaded Reducing Flange 4"X2" #150 RF. As per ASME B16.5
It is hubbed flange, as it appears at bimr's post above.

RE: Flange 4" 150 RF Blind c/w 2" NPT Center Tap A105 N

Yes, you are correct Big Inch. It is a blind flange that is drilled and tapped.

Shmulik is correct as well, but the poster has not said that this is a code piping application.

While the Blind flange is used to cap off the end of a pipeline or a future branch connection it is also used for other purposes. It can be drilled and tapped for a threaded reducing flange or machined out for a Slip-On reducing flange. The reduced opening can be either on-center or eccentric.

Picture of blind flange.



Here is a picture showing a pipe screwed into a drilled and tapped blind flange.

RE: Flange 4" 150 RF Blind c/w 2" NPT Center Tap A105 N

It is not unusual to have a drain in a blind flange at the end of the piperack.

RE: Flange 4" 150 RF Blind c/w 2" NPT Center Tap A105 N

Apart from the

Quote:

Threaded Reducing Flange 4"X2" #150 RF. As per ASME B16.5
as mentioned by Shmulik, you can also order a
  • 4" Hig Hub Blind Flange
  • Class 150
  • 2" NPT hole
A reducing may be more expensive in some cases, although I think that in this case the flange from which the result is machined (i.e. either the Hig Hub Blind Flange, or the Reducing threaded flange) has the same starting point/geometry.

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