Page 86 - Pressure Vessel Design Manual

General Design 67
s5j$j(Ta Qo QO

Seal
welding
p3t
r'. I
.8t, min d, -
-

3/41 min
typical
Figure 248. Case 13: Crimped heads [l , Section UG-34(s)].
A Qo Qo

Stresses in Flat Heads QO Qo

Maximum stress occurs at the junction, is axial in direc-
tion, and may be in either the head or the shell. When
th/ts 5 1, the maximum stress is in the head at the junction.
When th/t, > 1, the maximum stress is in the shell at the
junction. The bending moment M, is a result of internal
forces No and Q,,.
e Internal force, Q(,.

e Bending moment, M,. Figure 2-39. Discontinutty at flat head and cylindrical shell juncture.

e Prim y bending stress in head, ab. Note: Primary bending
stress is maximum at the center of the head.
e Axial stress in shell at junction, [5, Equation 6.1221.

( - ) Inside head, compression
( + ) Outside head, tension
e Axial stress in shell atjunction, ah [5, Equation 6.1321.