B16.5 Flashcards
B16.5 applies to range of NPS and classes?
- 1/2” - 24”
2. Class 150-2500
B16.5 applies to type of requirements? (7)
-Pressure/Temperature Ratings • Markings • Materials • Testing • Dimensions • Designating openings • Tolerances
what governs when two different flange ratings are joined
lower rated that governs
develop leakage problems unless care is taken to avoid imposing severe external loads, for what 2 temp and respective class?
Above 400°F - for Class 150
Above 750°F - all others
Hydro requirements
Normal limit is 1.5 x the 100°F pressure rating of the flange rounded off to next highest 25 psi.
Ratings for WN Flanges are based on the hubs at the ,
weld end - which is calculated as pipe with a
wall thickness
All flanges and fittings shall be marked with: (7)
- Manufacturers name or trademark
- Material Specification (ASTM)
- Rating Class
- “B16” or “B16.5”
- Size
- “R” - (Ring Joint Flanges only)
- Temperature (optional)
Three kinds of bolting are given:
- High Strength A193 B7 or above in strength (Table 1 B)
- Intermediate Strength - A193 B5 or above in strength (Table 1B)
- Low Strength - <30 KSI yield strength (Table 1B)
Used only in Class 150/300 joints, -20°F to 400°F.
some carbon steels, may undergo a decrease in ductility when used
at low temperatures to such an extent as to be unable to safely resist shock loading, sudden changes of stress, or high stress concentration.
Ring joint gasket materials shall
conform to ASME B16.20
joint flanged is joined by
assembler
fitting leak testing duration? (3)
- «_space;2” = 1min
- 2.5 «_space;NPS «_space;8” = 2 mins
- NPS»_space; 10” = 3mins”
what makes up a flanged joint? (interrelated)
- flange
- bolting
- gaskets
scope of B16.5
for flanges and flanged fittings
class 150/300 have what ____ raised flange
0.06”
class 400 and above have what ____ raised flange
0.25”
no under tolerance allowed for
flange thickness
hydro for flanges/flanged fittins
- flanges = not required
2. flange fittings = not less than 1.5x100F routed to next highest 25 PSI
flat face bolting?
low/intermediate or high
what to use to judge flange face finishes?
visual comparison
flange pressure test must be at what temperature use for the P in H=1.5P and round to what?
100F —> round to next highest 25
pipe hydro equation )
= 1.5 x P X (St/Sd
flange pressure test equation?
=1.5 x P = P = 100F and round next highest to 25
high strength bolts
used in any flanged joints
intermediate strength botls
user verifies their ability to seat the selected gasket
low strength bolt
limited to 150/300# flanges
limited to 400 and -20F
IA gasket recommend when
low strength bolting is used
class 150# should use what type of gaskets?
IA/ IB
