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!

*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.

Jobs

UG-45 Nozzle Thickness on an F&D Head

UG-45 Nozzle Thickness on an F&D Head

(OP)
All,

I have a vessel with an F&D head full of nozzles. COMPRESS is requiring a minimum thickness of 0.337" on an 8" nozzle (limited by UG-45, Tb-1). This nozzle is located in the inner 80% of the F&D, therefore, it's in the spherical portion. The fabricator ordered his materials and has specified a SCH40 (0.322"). The fabricator claims that the tb1 value should be that of the hemi-head formula and not the Torishperical.

I've used this exemption in the past for nozzle reinforcements because it specifically allows it in UG-37 for torispherical heads but UG-45 doesn't specifically spell it out.

UG-37 (tr def):
(A)when the opening and its reinforcement are entirely within the spherical portion of a torispherical head , tr is the thickness required by 1-4(d), using M=1.


UG-45 (tb1 def):
tb1 = for vessels under internal pressure , the thickness (plus corrosion allowance) required for pressure (assuming E=1) for the shell or head at the location where the nozzle neck or other connection attaches to the vessel but in no case less than the minimum thickness specified for the material in UG-16(b).

COMPRESS automatically uses the UG-37 exemption for nozzle reinforcements when they land in the spherical portion, but holds to the torispherical formula for the UG-45, tb1 thickness.

Any input is appreciated .

RE: UG-45 Nozzle Thickness on an F&D Head

(OP)
I just figured it out....COMPRESS had the little note (ASME VIII-1-83-66 Interpretation applied) which states that just because the hemi-head formula is used in the reinforcement calcs (UG-37) doesn't mean it can be used for UG-45. Either UG-32(d) or 1-4 shall be used for the Tb1 on a torispherical head.

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


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