Page 51 - Pressure Vessel Design Manual

General Design 37

ASME Code [l]. This paragraph requires a discontinu- 4. Toriconical transitions are advisable to avoid the high
ity analysis of the cone-shell juncture. discontinuity stresses at the junctures for the following
3. No reinforcing rings or added reinforcement is required conditions:
at the intersections of cones and cylinders, providing a a. High pressure-greater than 300 pig.
knuckle radius meeting ASME Code requirements is b. High temperature-greater than 450 or 500°F.
used. The minimum knuckle radius for the large end c. Low temperature-less than -20°F.
is not less than the greater of 3t or 0.12(R+t). The d. Cyclic service (fatigue).
knuckle radius of the small end (flare) has no minimum.
(See [Reference 1, Figure UG-361).

PROCEDURE 2-7

DESIGN OF FLANGES [ 1, 41

MG = moment due to HG, in.-lb
Notation M, =total moment on flange, operating, in.&
ML =total moment on flange, seating
A = flange O.D., in. MT = moment due to HT, in.-lb
AI, =cross-sectional area of bolts, in. 2 m = gasket factor (see Table 2-3)
A,,, =total required cross-sectional area of m, = unit load, operating, lb
bolts, in2 mg = unit load, gasket seating, lb
a = nominal bolt diameter, in. N =width of gasket, in. (see Table 2-4)
B =flange I.D., in. (see Note 6) w =width of raised face or gasket contact width,
B1 =flange I.D., in. (see Note 6) in. (see Table 2-4)
B, =bolt spacing, in. n = number of bolts
b = effective gasket width, in. u = Poisson’s ratio, 0.3 for steel
b,, = gasket seating width, in. P = design pressure, psi
C =bolt circle diameter, in. S, = allowable stress, bolt, at ambient temperature,
d =hub shape factor psi
dl =bolt hole diameter, in. S,, = allowable stress, bolt, at design temperature,
E, hI), hc;, hT, R =radial distances, in. psi
e =hub shape factor Sf, = allowable stress, flange, at ambient tempera-
F =hub shape factor for integral-type ture, psi
flanges Sf,, = allowable stress, flange, at design temperature,
FL, =hub shape factor for loose-type flanges psi
f = hub stress correction factor for integral SH =longitudinal hub stress, psi
flanges SR = radial stress in flange, psi
G = diameter at gasket load reaction, in. ST =tangential stress in flange, psi T, U, Y
% =thickness of hub at small end, in. Z = K-factors (see Table 2-5)
gl =thickness of hub at back of flange, in. T,, U,, Y, = K-factors for reverse flanges
H =hydrostatic end force, lb t = flange thickness, in.
HD =hydrostatic end force on area inside of t, =pipe wall thickness, in.
flange, lb V =hub shape factor for integral
HG = gasket load, operating, lb flanges
H, = total joint-contact surface compression VL =hub shape factor for loose flanges
load, lb W = flange design bolt load, lb
HT =pressure force on flange face, lb Wml = required bolt load, operating, lb
h =hub length, in. Wrrr2 = required bolt load, gasket seating, Ib
h, =hub factor y = gasket design seating stress, psi
MD = moment due to HD, in.-lb