- A
flange O.D., in.
- Ab
cross-sectional area of bolts, in.2
- Am
total required cross-sectional area of bolts, in.2
- a
nominal bolt diameter, in.
- B
flange I.D., in.
- B1
flange I.D., in.
- Bs
bolt spacing, in.
- b
effective gasket width, in.
- bo
gasket seating width, in.
- C
bolt circle diameter, in.
- d
hub shape factor
- d1
bolt hole diameter, in.
- E, hD, hG, hT, R
radial distances, in.
- e
hub shape factor
- F
hub shape factor for integral-type flanges
- FL
hub shape factor for loose-type flanges
- f
hub stress correction factor for integral flanges
- G
diameter at gasket load reaction, in.
- go
thickness of hub at small end, in.
- g1
thickness of hub at back of flange, in.
- H
hydrostatic end force, lb
- HD
hydrostatic end force on area inside of flange, lb
- HG
gasket load, operating, lb
- Hp
total joint-contact surface compression load, lb
- HT
pressure force on flange face, lb
- h
hub length, in.
- ho
hub factor
- MD
moment due to HD, in.-lb
- MG
moment due to HG, in.-lb
- Mo
total moment on flange, operating, in.-lb
- M′o
total moment on flange, seating
- MT
moment due to HT, in.-lb
- m
gasket factor
- mo
unit load, operating, lb
- mg
unit load, gasket seating, lb
- N
width of gasket, in.
- n
number of bolts
- v
Poisson's ratio, 0.3 for steel
- P
design pressure, psi
- Sa
allowable stress, bolt, at ambient temperature, psi
- Sb
allowable stress, bolt, at design temperature, psi
- Sfa
allowable stress, flange, at ambient temperature, psi
- Sfo
allowable stress, flange, at design temperature, psi
- SH
longitudinal hub stress, psi
- SR
radial stress in flange, psi
- ST
tangential stress in flange, psi
- T, U, Y, Z
K-factors (see Table 3-6)
- Tr, Ur, Yr
K-factors for reverse flanges
- t
flange thickness, in.
- tn
pipe wall thickness, in.
- V
hub shape factor for integral flanges
- VL
hub shape factor for loose flanges
- W
flange design bolt load, lb
- Wm1
required bolt load, operating, lb
- Wm2
required bolt load, gasket seating, lb
- w
width of raised face or gasket contact width, in. (See Table 3-5)
- y
gasket design seating stress, psi