×
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

Design of Reinforcement openings.

Design of Reinforcement openings.

Design of Reinforcement openings.

(OP)
Dear All,

Please i have been studying a book "Guidebook for the design of ASME Section VIII Pressure Vessel" by James R. Farr and Mann H. Jawad.

Reference to the attachment Example 5.1. highlighted in yellow for the calculation of reinforcement openings. After the calculation of the minimum required thickness of the ellipsoidal head, to be 0.733in, they selected the nominal thickness as 0.75in.

how did they arrive at this value?

And also, for the calculation of the required nozzle thickness, after solving to get the value as 0.143in , the nominal thickness selected was 1.125in.

How was this arrived?

this is quite confusing and i need some assistance, how these nominal thickness was selected.

Thanks in advance for your help.

RE: Design of Reinforcement openings.

a) In the case that you are studying, you have to understand the nuance between required thickness (Tr) and nomimal thickness (Tn). The nominal thickness is the thickness of the head provided by the manufacturer within some tolerances. Since Tr < Tn you are OK with the design.
b) The required thickness (Tr) is less than the actual nozzle thickness (T) used in this example. The nozzle thickness (T) which appears to be excessive for other reasons not revealed in this example is whatwas commercially available and used in the design. Since Tr < T you are OK with the design.

RE: Design of Reinforcement openings.

I don't see how .750" would be sufficient for this problem. 10% thinning due to forming would leave .675" min. thickness of the head....below min. required.

RE: Design of Reinforcement openings.

ASME VIII Div.1 MANDATORY APPENDIX 3 DEFINITIONS:3.2.(c) nominal thickness: except as defined in UW-40(f)
and modified in UW-11(g), the nominal thickness is the thickness selected as commercially available, and supplied to the Manufacturer. For plate material, the nominal thickness shall be, at the Manufacturer’s option, either the thickness shown on
the Material Test Report {or material Certificate of Compliance [UG-93(a)(1)]} before forming, or the measured thickness of the plate at the joint or location under consideration.

Regards
r6155

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