ASME B31.8 Gas Pipeline Flexibility And Stress Factor

Calculate ASME B31.8 flexibility

stress intensity factors
allowable cyclic stress
stress range factor
longitudinal stress
flexibility stress

Refer to the figures for symbols.

Reference : ANSI/ASME B31.8 : Gas Pipelines

Change Module :

ASME B31 Pipe Diameter And Wall Thickness Schedule Calculation Module
ASME B31 Stress Intensity Factor Calculation Module
ASME B31.1 Power Piping Flexibility And Stress Factor Calculation Module
ASME B31.3 Process Piping Flexibility And Stress Factor Calculation Module
ASME B31.4 Liquid Pipeline Flexibility And Stress Factor Calculation Module
ASME B31.5 Refrigeration Piping Flexibility And Stress Factor Calculation Module
All

Related Modules :

ASME B31.8 Gas Pipeline Calculation Module
More Fatigue Damage Modules

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Links : ±

CALCULATOR : ASME B31.8 Metal Pipe Diameter And Wall Thickness Schedule [FREE] ±

Calculate ASME B31.8 metal pipe diameter and pressure design wall thickness from pipe schedule or user defined diameter and wall thickness (ASME B31.8 section 841.1). For ASME B31.8 the fabrication tolerance is accounted for in the design factor. The fabrication tolerance is ignored when calculating the pressure design thickness. The pressure design thickness equals the nominal thickness minus the corrosion allowance.

Select the pipe schedule (NPS or ISO), pipe diameter and wall thickness, or use the user defined option. Use the Result Table option to display the pipe schedule with nominal wall thickness and pressure design wall thickness for the selected diameter. Fabrication tolerance is ignored.

Tool Input

schdtype : Line Pipe Schedule Type
diamtype : Line Pipe Diameter Type
- ODu : User Defined Outside Diameter
- IDu : User Defined Inside Diameter
wtntype : Wall Thickness Type
- tnu : User Defined Wall Thickness
c : Wall Thickness Corrosion Allowance

Tool Output

ID : Nominal Inside Diameter
OD : Nominal Outside Diameter
OD/tn : Diameter Over Wall Thickness Ratio
tn : Nominal Wall Thickness
tp : Pressure Design Wall Thickness

CALCULATOR : ASME B31.8 Section 841.1 Pipeline Temperature Derated Yield Stress And Tensile Stress [FREE] ±

Calculate temperature derating factor, and derated yield stress and tensile stress from temperature (ASME B31.8 section 841.1).

Refer to Table 841.1.8-1 for the derating factors. The derating factors are valid for steel pipe upto 232 C (450 F). For temperatures above 232 C (450 F) the derating values should be used carefully (material specific test data should be used if it is available). The derating factor is assumed to be valid for yield stress and tensile stress. Use the Result Table option to display the results for the selected stress table (API, ASME or DNV). The temperature derating factor is not valid for nickel alloy, or stainless steel.

Tool Input

syutype : Stress Table Type
mattype : Material Type
- SMYSu : User Defined Specified Minimum Yield Stress
- SMTSu : User Defined Specified Minimum Tensile Stress
tfactype : Temperature Derating Factor Type
- Td : Design Temperature
- Tu : User Defined Temperature Derating Factor

Tool Output

SMTS : Specified Minimum Tensile Stress
SMTS/SMYS : Tensile Stress Over Yield Stress Ratio
SMYS : Specified Minimum Yield Stress
SMYS/SMTS : Yield Stress Over Tensile Stress Ratio
Su : Derated Tensile Stress
Sy : Derated Yield Stress
T : Temperature Derating Factor

CALCULATOR : ASME B31.8 Pipeline Local Pressure From Elevation (Onshore) [FREE] ±

Calculate ASME B31.8 gas pipeline local stationary internal pressure from elevation for onshore pipelines.

For onshore pipelines external pressure is ignored. Elevation is measured relative to an arbitrary datum (see figure). Mean sea level (MSL) is commonly used as a datum.

Tool Input

plitype : Internal Pressure Type
- Priu : User Defined Reference Internal Pressure
- Pliu : User Defined Local Internal Pressure
- ρf : Internal Fluid Density
- Zr : Reference Elevation
- Zl : Local Elevation

Tool Output

ΔZlr : Local Elevation Relative To Reference Elevation
Pli : Internal Fluid Pressure

CALCULATOR : ASME B31.8 Pipeline Local Pressure From Elevation (Offshore) [FREE] ±

Calculate ASME B31.8 gas pipeline local stationary internal and external pressure from elevation for offshore pipelines.

For platform piping and the riser section above sea level the external pressure should be ignored (select the local external pressure = 0 option). Elevation is measured relative to an arbitrary datum (see figure). Mean sea level (MSL) is commonly used as a datum.

Tool Input

plitype : Internal Pressure Type
- Priu : User Defined Reference Internal Pressure
- Pliu : User Defined Local Internal Pressure
- ρf : Internal Fluid Density
- Zr : Reference Elevation
- Zl : Local Elevation
pletype : External Pressure Type
- Pleu : User Defined Local External Pressure
- ρe : External Fluid Density
- Zs : Surface Elevation

Tool Output

ΔPl : Delta Pressure Across Pipe Wall
ΔZlr : Local Elevation Relative To Reference Elevation
Ple : External Fluid Pressure
Pli : Internal Fluid Pressure
wd : Water Depth

CALCULATOR : Pipeline Combined Stress Check [PLUS] ±

Calculate axial load, combined stress, hoop stress, longitudinal stress, bending stress and torsion stress for onshore and offshore pipelines.

The axial load is calculated using the thick wall formula (API RP 1111 and DNVGL ST F101). Loads are positive in tension, and negative in compression. The external pressure is assumed constant for installation and operation (submerged pipeline). The internal pressure is assumed zero for installation.

The combined stress may be calculated using either Tresca's or Von Mises' formula. Generally, the combined stress should be less than or equal to 90% of yield. The stress check can be calculated for either the nominal wall thickness, or the corroded wall thickness (nominal wall thickness minus corrosion allowance).

Tool Input

pletype : External Pressure Type
- Peu : User Defined External Pressure
syutype : Stress Table Type
mattype : Yield Stress Type
- SMYSu : User Defined Specified Minimum Yield Stress
schdtype : Pipe Schedule Type
diamtype : Pipe Diameter Type
- ODu : User Defined Outside Diameter
- IDu : User Defined Inside Diameter
wtntype : Wall Thickness Type
- tnu : User Defined Wall Thickness
corrtype : Pipe Wall Corrosion Type
modptype : Pipe Material Type
- νu : User Defined Pipe Poisson's Ratio
- αu : User Defined Pipe Thermal Expansion Coefficient
- Eu : User Defined Pipe Elastic Modulus
sectype : Pipe Section Properties Type
- Asu : User Defined Steel Cross Section Area
- EAαu : User Defined Pipe E x A x alpha
- Zu : User Defined Pipe Z Modulus
walltype : Hoop Stress Calculation Type
- Yu : User Defined ASME Y Factor
loadtype : Axial Load Type
- Fgu : User Defined Global Axial Load
- Fwu : User Defined Pipe Wall Axial Load
ifactype : Stress Factor Type
- iiu : User Defined In Plane Bending Stress factor
- iou : User Defined Out Of Plane Bending Stress Factor
- itu : User Defined Torsion Shear Stress Factor
sbtype : Bending Stress Type
sttype : Torsion Shear Stress Type
checktype : Stress Check Type
momtype : Bending Stress Type
tc : Corrosion Allowance
Fd : Design Factor
Td : Design Temperature
Pi : Internal Pressure
Tin : Installation Temperature
Fin : Installation Load
M : Design Moment

Tool Output

α : Pipe Thermal Expansion Coefficient
ν : Pipe Poisson's Ratio
Ax : Pipe Cross Section Area
E : Pipe Elastic Modulus
EAα : Pipe E x A x alpha
Fg : Global Or External Axial Load
Fw : Pipe Wall Axial Load
ID : Pipe Inside Diameter
OD : Pipe Outside Diameter
OD/t : Pipe Diameter Over Wall Thickness Ratio
PΔ : Pressure Difference
Pe : External Pressure
SMYS : Specified Minimum Yield Stress
Sb : Bending Stress
Schk : Check Stress
Schk/Sd : Hoop Stress Over Allowable Stress Ratio
Sd : Design Stress
Sh : Hoop Stress
St : Torsion Stress
Sx : Pipe Wall Axial Stress
Z : Z Section Modulus
ii : In Plane Bending Stress Factor
io : Out Of Plane Bending Stress Factor
it : Torsion Shear Stress Factor
t : Stress Check Wall Thickness
tn : Pipe Nominal Wall Thickness

CALCULATOR : Pipeline Axial Load From Temperature And Pressure [PLUS] ±

Calculate pipeline restrained and unrestrained global or external axial load and wall load from temperature and pressure for single layer pipelines.

The external pressure is assumed to be constant during installation and operation (submerged pipeline). The internal pressure is assumed to be zero during installation.

Pipeline section properties are either calculated or user defined. The axial load is calculated using the thick wall formula (API RP 1111 and DNVGL ST F101). Loads are positive in tension, and negative in compression.

The axial load can be calculated for either the nominal wall thickness, or the corroded wall thickness (nominal wall thickness minus corrosion allowance).

Tool Input

pletype : External Pressure Type
- Peu : User Defined External Pressure
syutype : Stress Table Type
mattype : Yield Stress Type
- SMYSu : User Defined Specified Minimum Yield Stress
schdtype : Pipe Schedule Type
diamtype : Pipe Diameter Type
- ODu : User Defined Outside Diameter
- IDu : User Defined Inside Diameter
wtntype : Wall Thickness Type
- tnu : User Defined Wall Thickness
corrtype : Pipe Wall Corrosion Type
modptype : Pipe Material Type
- νu : User Defined Pipe Poisson's Ratio
- αu : User Defined Pipe Thermal Expansion Coefficient
- Eu : User Defined Pipe Elastic Modulus
sectype : Pipe Section Properties Type
- Asu : User Defined Steel Cross Section Area
- EAαu : User Defined Pipe E x A x alpha
loadtype : Axial Load Type
- Fgu : User Defined Global Axial Load
- Fwu : User Defined Pipe Wall Axial Load
tc : Corrosion Allowance
Fd : Design Factor
Pi : Internal Pressure
Td : Design Temperature
Tin : Installation Temperature
Fin : Installation Load

Tool Output

α : Pipe Thermal Expansion Coefficient
ν : Pipe Poisson's Ratio
Ax : Pipe Cross Section Area
E : Pipe Elastic Modulus
EAα : Pipe E x A x alpha
Fg : Global Or External Axial Load
Fw : Pipe Wall Axial Load
ID : Pipe Inside Diameter
OD : Pipe Outside Diameter
OD/tn : Pipe Diameter Over Wall Thickness Ratio
PΔ : Pressure Difference
Pe : External Pressure
SMYS : Specified Minimum Yield Stress
Sd : Allowable Stress
Sw : Pipe Wall Axial Stress
Sw/Sd : Axial Stress Over Allowable Stress Ratio
t : Stress Check Wall Thickness
tn : Pipe Nominal Wall Thickness

CALCULATOR : Pipeline Local Pressure From Elevation (Offshore Pipeline) [FREE] ±

Calculate offshore pipeline local stationary internal pressure and external pressure from elevation using Bernoulli's equation.

The local internal pressure is calculated from the reference pressure and relative elevation. The external pressure is calculated from the water depth. The internal fluid density is assumed constant.

Tool Input

pletype : External Pressure Type
- Pleu : User Defined Local External Pressure
plitype : Internal Pressure Type
- Priu : User Defined Reference Internal Pressure
- Pliu : User Defined Local Internal Pressure
ρf : Internal Fluid Density
ρe : External Fluid Density
Zr : Reference Elevation Relative To Datum
Zl : Local Elevation Relative To Datum
Zs : Surface Elevation Relative To Datum

Tool Output

ΔPl : Pressure Difference Across Pipe Wall
Δz : Local Elevation Relative To Reference Elevation
Ple : External Pressure
Pli : Internal Pressure At Local Elevation
Pri : Internal Pressure At Reference Elevation
wd : Water Depth

CALCULATOR : ASME B31.8 Appendix E Stress Intensity Factors Elbow Or Bend [FREE] ±

Calculate ASME B31.8 Appendix E stress intensity factors for elbows and bends. Calculate flexibility characteristic h, flexibility factor k, and stress intensification factors ii and io for pipe elbows and bends (ASME B31.8 appendix E).

The pipe mean diameter is calculated at the mid nominal wall thickness.

Tool Input

diamtype : Pipe Diameter Type
- Du : User Defined Outside Diameter
- du : User Defined Inside Diameter
petype : External Pressure Type
- Peu : User Defined External Pressure
codetype : ASME B31 Code
bendtype : Bend Radius Type
- R/Du : User Defined Bend Radius Over Diameter Ratio
- Ru : User Defined Bend Radius
endtype : Flanged Or Welded Connection
isfactype : Stress Factor Multiplier Type
- i*u : User Defined Stress Factor Multiplier
t : Pipe Nominal Wall Thickness
E : Elastic Modulus
P : Internal Pressure

Tool Output

ΔP : Pressure Difference
D : Pipe Outside Diameter
D/tn : Pipe Diameter Over Wall Thickness Ratio
Pe : External Pressure
R : Pipe Bend Radius
R/D : Bend Radius Over Pipe Diameter Ratio
c : Flange Correction Factor
d : Pipe Inside Diameter
dm : Pipe Mid Wall Diameter
h : Flexibility Characteristic
i* : Stress Factor Multiplier
ii : In Plane Stress Intensity Factor (≥ 1)
io : Out Of Plane Stress Intensity Factor (≥ 1)
k : Flexibility Factor
pi : Pressure i Correction Factor
pk : Pressure k Correction Factor
r : Pipe Mid Wall Radius

CALCULATOR : ASME B31.8 Appendix E Stress Intensity Factors Miter Bend Single [FREE] ±

Calculate ASME B31.8 Appendix E stress intensity factors for single miter bends. Calculate flexibility characteristic h, flexibility factor k, and stress intensification factors ii and io for pipe elbows and bends (ASME B31.8 appendix E).

The pipe mean diameter is calculated at the mid nominal wall thickness.

Tool Input

diamtype : Pipe Diameter Type
- Du : User Defined Outside Diameter
- du : User Defined Inside Diameter
petype : External Pressure Type
- Peu : User Defined External Pressure
codetype : ASME B31 Code
isfactype : Stress Factor Multiplier Type
- i*u : User Defined Stress Factor Multiplier
θ : Miter Half Angle
t : Pipe Nominal Wall Thickness
E : Elastic Modulus
P : Internal Pressure

Tool Output

ΔP : Pressure Difference
D : Pipe Outside Diameter
D/tn : Pipe Diameter Over Wall Thickness Ratio
Pe : External Pressure
R : Miter Radius
d : Pipe Inside Diameter
dm : Pipe Mid Wall Diameter
h : Flexibility Characteristic
i* : Stress Factor Multiplier
ii : In Plane Stress Intensity Factor (≥ 1)
io : Out Of Plane Stress Intensity Factor (≥ 1)
k : Flexibility Factor
pi : Pressure i Correction Factor
pk : Pressure k Correction Factor
r : Pipe Mid Wall Radius

CALCULATOR : ASME B31.8 Appendix E Stress Intensity Factors Miter Bend Compound [FREE] ±

Calculate ASME B31.8 Appendix E stress intensity factors for compound miter bends. Calculate flexibility characteristic h, flexibility factor k, and stress intensification factors ii and io for pipe elbows and bends (ASME B31.8 appendix E).

The pipe mean diameter is calculated at the mid nominal wall thickness.

Tool Input

diamtype : Pipe Diameter Type
- Du : User Defined Outside Diameter
- du : User Defined Inside Diameter
petype : External Pressure Type
- Peu : User Defined External Pressure
codetype : ASME B31 Code
endtype : Flanged Or Welded Connection
isfactype : Stress Factor Multiplier Type
- i*u : User Defined Stress Factor Multiplier
θ : Miter Bend Half Angle
s : Miter Center Line Length
t : Pipe Nominal Wall Thickness
E : Elastic Modulus
P : Internal Pressure

Tool Output

ΔP : Pressure Difference
D : Pipe Outside Diameter
D/tn : Pipe Diameter Over Wall Thickness Ratio
Pe : External Pressure
R : Miter Radius
c : Flange Correction Factor
d : Pipe Inside Diameter
dm : Pipe Mid Wall Diameter
h : Flexibility Characteristic
i* : Stress Factor Multiplier
ii : In Plane Stress Intensity Factor
io : Out Of Plane Stress Intensity Factor
k : Flexibility Factor
pi : Pressure i Correction Factor
pk : Pressure k Correction Factor
r : Pipe Mid Wall Radius
st : Miter Transition Length (Wide Or Close Spacing)

CALCULATOR : ASME B31.8 Appendix E Stress Intensity Factors Welding Tee [FREE] ±

Calculate ASME B31.8 Appendix E stress intensity factors for welding tees. Calculate flexibility characteristic h, flexibility factor k, and stress intensification factors ii and io for pipe branches, tees and inserts (ASME B31.8 appendix E).

The pipe mean diameter is calculated at the mid nominal wall thickness.

Tool Input

diamtype : Header Diameter Type
- Du : User Defined Outside Diameter
- du : User Defined Inside Diameter
codetype : ASME B31 Code
loadtype : Number Of Load Cycles (ASME B31.8 Only)
isfactype : Stress Factor Multiplier Type
- i*u : User Defined Stress Factor Multiplier
t : Header Nominal Wall Thickness
Db : Branch Outside Diameter
rc : Crotch Radius
tc : Crotch Wall Thickness

Tool Output

D : Header Outside Diameter
D/tn : Header Diameter Over Wall Thickness Ratio
d : Header Inside Diameter
d/D : Branch To Header Diameter Ratio
dm : Header Mid Wall Diameter
h : Flexibility Characteristic
i* : Stress Factor Multiplier
ii : In Plane Stress Intensity Factor (≥ 1)
io : Out Of Plane Stress Intensity Factor (≥ 1)
k : Flexibility Factor
r : Header Mid Wall Radius

CALCULATOR : ASME B31.8 Appendix E Stress Intensity Factors Extruded Welding Tee [FREE] ±

Calculate ASME B31.8 Appendix E stress intensity factors for extruded welding tees. Calculate flexibility characteristic h, flexibility factor k, and stress intensification factors ii and io for pipe branches, tees and inserts (ASME B31.8 appendix E).

The pipe mean diameter is calculated at the mid nominal wall thickness.

Tool Input

diamtype : Header Diameter Type
- Du : User Defined Outside Diameter
- du : User Defined Inside Diameter
codetype : ASME B31 Code
loadtype : Number Of Load Cycles (ASME B31.8 Only)
isfactype : Stress Factor Multiplier Type
- i*u : User Defined Stress Factor Multiplier
t : Header Nominal Wall Thickness
Db : Branch Outside Diameter
rc : Crotch Radius
tc : Crotch Wall Thickness

Tool Output

D : Header Outside Diameter
D/tn : Header Diameter Over Wall Thickness Ratio
d : Header Inside Diameter
d/D : Branch To Header Diameter Ratio
dm : Header Mid Wall Diameter
h : Flexibility Characteristic
i* : Stress Factor Multiplier
ii : In Plane Stress Intensity Factor (≥ 1)
io : Out Of Plane Stress Intensity Factor (≥ 1)
k : Flexibility Factor
r : Header Mid Wall Radius

CALCULATOR : ASME B31.8 Appendix E Stress Intensity Factors Reinforced Fabricated Tee [FREE] ±

Calculate ASME B31.8 Appendix E stress intensity factors for reinforced fabricated tees. Calculate flexibility characteristic h, flexibility factor k, and stress intensification factors ii and io for pipe branches, tees and inserts (ASME B31.8 appendix E).

The pipe mean diameter is calculated at the mid nominal wall thickness.

Tool Input

diamtype : Header Diameter Type
- Du : User Defined Outside Diameter
- du : User Defined Inside Diameter
codetype : ASME B31 Code
loadtype : Number Of Load Cycles (ASME B31.8 Only)
isfactype : Stress Factor Multiplier Type
- i*u : User Defined Stress Factor Multiplier
t : Header Nominal Wall Thickness
Db : Branch Outside Diameter
tr : Reinforcement Thickness

Tool Output

D : Header Outside Diameter
D/tn : Header Diameter Over Wall Thickness Ratio
d : Header Inside Diameter
d/D : Branch To Header Diameter Ratio
dm : Header Mid Wall Diameter
h : Flexibility Characteristic
i* : Stress Factor Multiplier
ii : In Plane Stress Intensity Factor (ASME B31.8 ≥ 1.2 : Others ≥ 1)
io : Out Of Plane Stress Intensity Factor (ASME B31.8 ≥ 1.2 : Others ≥ 1)
k : Flexibility Factor
r : Header Mid Wall Radius

CALCULATOR : ASME B31.8 Appendix E Stress Intensity Factors Unreinforced Fabricated Tee [FREE] ±

Calculate ASME B31.8 Appendix E stress intensity factors for unreinforced fabricated tees. Calculate flexibility characteristic h, flexibility factor k, and stress intensification factors ii and io for pipe branches, tees and inserts (ASME B31.8 appendix E).

The pipe mean diameter is calculated at the mid nominal wall thickness.

Tool Input

diamtype : Header Diameter Type
- Du : User Defined Outside Diameter
- du : User Defined Inside Diameter
codetype : ASME B31 Code
loadtype : Number Of Load Cycles (ASME B31.8 Only)
isfactype : Stress Factor Multiplier Type
- i*u : User Defined Stress Factor Multiplier
t : Header Nominal Wall Thickness
Db : Branch Outside Diameter

Tool Output

D : Header Outside Diameter
D/tn : Header Diameter Over Wall Thickness Ratio
d : Header Inside Diameter
d/D : Branch To Header Diameter Ratio
dm : Header Mid Wall Diameter
h : Flexibility Characteristic
i* : Stress Factor Multiplier
ii : In Plane Stress Intensity Factor (≥ 1)
io : Out Of Plane Stress Intensity Factor (≥ 1)
k : Flexibility Factor
r : Header Mid Wall Radius

CALCULATOR : ASME B31.8 Appendix E Stress Intensity Factors Welded In Contour Insert [FREE] ±

Calculate ASME B31.8 Appendix E stress intensity factors for welded in contour inserts. Calculate flexibility characteristic h, flexibility factor k, and stress intensification factors ii and io for pipe branches, tees and inserts (ASME B31.8 appendix E).

The pipe mean diameter is calculated at the mid nominal wall thickness.

Tool Input

diamtype : Header Diameter Type
- Du : User Defined Outside Diameter
- du : User Defined Inside Diameter
codetype : ASME B31 Code
loadtype : Number Of Load Cycles (ASME B31.8 Only)
isfactype : Stress Factor Multiplier Type
- i*u : User Defined Stress Factor Multiplier
t : Header Nominal Wall Thickness
Db : Branch Outside Diameter
rc : Crotch Radius
tc : Crotch Wall Thickness

Tool Output

D : Header Outside Diameter
D/tn : Header Diameter Over Wall Thickness Ratio
d : Header Inside Diameter
d/D : Branch To Header Diameter Ratio
dm : Header Mid Wall Diameter
h : Flexibility Characteristic
i* : Stress Factor Multiplier
ii : In Plane Stress Intensity Factor (≥ 1)
io : Out Of Plane Stress Intensity Factor (≥ 1)
k : Flexibility Factor
r : Header Mid Wall Radius

CALCULATOR : ASME B31.8 Appendix E Stress Intensity Factors Welded on Branch Integrally Reinforced [FREE] ±

Calculate ASME B31.8 Appendix E stress intensity factors for integrally reinforced welded on branch. Calculate flexibility characteristic h, flexibility factor k, and stress intensification factors ii and io for pipe branches, tees and inserts (ASME B31.8 appendix E).

The pipe mean diameter is calculated at the mid nominal wall thickness.

Tool Input

diamtype : Header Diameter Type
- Du : User Defined Outside Diameter
- du : User Defined Inside Diameter
codetype : ASME B31 Code
isfactype : Stress Factor Multiplier Type
- i*u : User Defined Stress Factor Multiplier
t : Header Nominal Wall Thickness
Db : Branch Outside Diameter

Tool Output

D : Header Outside Diameter
D/tn : Header Diameter Over Wall Thickness Ratio
d : Header Inside Diameter
d/D : Branch To Header Diameter Ratio
dm : Header Mid Wall Diameter
h : Flexibility Characteristic
i* : Stress Factor Multiplier
ii : In Plane Stress Intensity Factor (≥ 1)
io : Out Of Plane Stress Intensity Factor (≥ 1)
k : Flexibility Factor
r : Header Mid Wall Radius

CALCULATOR : ASME B31.8 Appendix E Stress Intensity Factors Butt Weld [FREE] ±

Calculate ASME B31.8 Appendix E stress intensity factors for butt welds. Calculate flexibility factor k, and stress intensification factors ii and io for pipe welds and joints (ASME B31.8 appendix E).

Tool Input

codetype : ASME B31 Code
isfactype : Stress Factor Multiplier Type
- i*u : User Defined Stress Factor Multiplier
t : Pipe Nominal Wall Thickness
δmax : Maximum Weld Offset
δavg : Average Weld Offset

Tool Output

δ/t : Average Weld Offset Over Pipe Wall Thickness Ratio
i : Stress Intensity Factor
i* : Stress Factor Multiplier
k : Flexibility Factor

CALCULATOR : ASME B31.8 Appendix E Stress Intensity Factors Tapered Transition [FREE] ±

Calculate ASME B31.8 Appendix E stress intensity factors for tapered transitions. Calculate flexibility factor k, and stress intensification factors ii and io for pipe welds and joints (ASME B31.8 appendix E).

Tool Input

codetype : ASME B31 Code
diamtype : Pipe Diameter Type
- Du : User Defined Outside Diameter
- du : User Defined Inside Diameter
isfactype : Stress Factor Multiplier Type
- i*u : User Defined Stress Factor Multiplier
t : Pipe Nominal Wall Thickness
δ : Weld Offset

Tool Output

δ/t : Average Weld Offset Over Pipe Wall Thickness Ratio
D : Pipe Outside Diameter
D/tn : Pipe Diameter Over Wall Thickness Ratio
d : Pipe Inside Diameter
i : Stress Intensity Factor
i* : Stress Factor Multiplier
k : Flexibility Factor

CALCULATOR : ASME B31.8 Appendix E Stress Intensity Factors Concentric Reducer [FREE] ±

Calculate ASME B31.8 Appendix E stress intensity factors for concentric reducers. Calculate flexibility factor k, and stress intensification factors ii and io for pipe welds and joints (ASME B31.8 appendix E).

Tool Input

codetype : ASME B31 Code
diamtype : Reducer Small End Diameter Type
- Du : User Defined Outside Diameter
- du : User Defined Inside Diameter
isfactype : Stress Factor Multiplier Type
- i*u : User Defined Stress Factor Multiplier
t : Reducer Small End Nominal Wall Thickness
α : Reducer Cone Half Angle

Tool Output

D : Reducer Small End Outside Diameter
D/tn : Reducer Diameter Over Wall Thickness Ratio
d : Reducer Small End Inside Diameter
i : Stress Intensity Factor
i* : Stress Factor Multiplier
k : Flexibility Factor

CALCULATOR : ASME B31.8 Appendix E Stress Intensity Factors Socket Weld [FREE] ±

Calculate ASME B31.8 Appendix E stress intensity factors for socket welds. Calculate flexibility factor k, and stress intensification factors ii and io for pipe welds and joints (ASME B31.8 appendix E).

Tool Input

codetype : ASME B31 Code
isfactype : Stress Factor Multiplier Type
- i*u : User Defined Stress Factor Multiplier
t : Pipe Nominal Wall Thickness
C : Fillet Weld Length

Tool Output

i : Stress Intensity Factor
i* : Stress Factor Multiplier
k : Flexibility Factor
tn/C : Pipe Wall Thickness Over Fillet Weld Length Ratio

CALCULATOR : ASME B31.8 Appendix E Stress Intensity Factors Miscellaneous [FREE] ±

Calculate flexibility factor k, and stress intensification factor i for double welded slip on flanges, fillet welds, lap joint flanges, threaded pipe and flanges, and corrugated pipe (ASME B31.8 appendix E).

Tool Input

pipetype : Pipe Or Joint Type
isfactype : Stress Factor Multiplier Type
- i*u : User Defined Stress Factor Multiplier

Tool Output

i : Stress Intensity Factor
i* : Stress Factor Multiplier
k : Flexibility Factor

CALCULATOR : ASME B31.8 Section 833.7 Maximum Displacement Flexibility Check [FREE] ±

Calculate pipe spool flexibility maximum displacement check (ASME B31.8 section 833.7). A formal flexibility assessment is generally not required for pipe sections with displacement less than the calculated maximum displacement. Reaction forces and moments may require separate analysis.

The developed pipe length is the length measured along the pipe center line. The difference between the developed length, and the straight line length is an approximate measure of the offsets in the line.

Tool Input

D : Nominal Outside Diameter
L : Developed Pipe Length Between Anchors
U : Straight Line Length Between Anchors
Sa : Allowable Stress
E : Young's Modulus

Tool Output

ymax : Maximum Total Displacement Strain

CALCULATOR : ASME B31.8 Section 833.8 Stress Range Factor [FREE] ±

Calculate the pipe stress range factor f from the number of stress cycles (ASME B31.8 section 833.8).

Tool Input

codetype : ASME B31 Code
ffactype : Stress Range Factor Type
- fmu : User Defined Maximum Stress Range Factor
- fu : User Defined Stress Range Factor
N : Number Of Cycles

Tool Output

f : Stress Range Factor
fm : Maximum Stress Range Factor

CALCULATOR : ASME B31.8 Section 833.8 Allowable Cyclic Stress From Number Of Cycles [FREE] ±

Calculate the allowable cyclic stress from the number of stress cycles (ASME B31.8 section 833.8).

The longitudinal stress is optional (the longitudinal stress is used to calculate the allowable stress if the longitudinal stress is less the allowable stress at maximum temperature). Sc equals 1/3 of the ultimate stress at the minimum temperature. Sh equals 1/3 of the ultimate stress at the maximum temperature.

Tool Input

codetype : ASME B31 Code
ffactype : Stress Range Factor Type
- fmu : User Defined Maximum Stress Range Factor
- fu : User Defined Stress Range Factor
sactype : Allowable Cyclic Stress Type
S : Design Stress
N : Number Of Cycles

Tool Output

Sa : Allowable Cyclic Stress
f : Stress Range Factor
fm : Maximum Stress Range Factor

CALCULATOR : ASME B31.8 Section 833.8 Allowable Cyclic Stress From Equivalent Number Of Load Cycles [FREE] ±

Calculate the allowable cyclic stress from cyclic stress data (ASME B31.8 section 833.8). Enter the cyclic stress data as comma or tab separated pairs (number of cycles, cyclic stress), with each data pair on a new line (or copy and paste cells from a spreadsheet).

The longitudinal stress is optional (the longitudinal stress is used to calculate the allowable stress if the longitudinal stress is less the allowable stress at maximum temperature).

Tool Input

codetype : ASME B31 Code
ffactype : Stress Range Factor Type
- fmu : User Defined Maximum Stress Range Factor
- fu : User Defined Stress Range Factor
sactype : Allowable Cyclic Stress Type
S : Design Stress
Ndata : Load Cycles Data Values
Sdata : Load Stress Data Values

Tool Output

Ne : Number Of Cycles
Sa : Allowable Cyclic Stress
Se : Maximum Cyclic Stress
Se/Sa : Cyclic Stress Over Allowable Stress Ratio
f : Stress Range Factor
fm : Maximum Stress Range Factor

CALCULATOR : ASME B31.8 Section 833.8 Design Stress Sc And Sh From Temperature [FREE] ±

Calculate design stress Sc and Sh from temperature for carbon steel and low alloy steel (ASME B31.8 section 833.8 and 841.1).

Sc and Sh are used to calculate the allowable stress for cyclic loading. Sc and Sh can be calculated individually by:

`Sc = 2/3 Symin `
`Sh = 2/3 Symax `

where :

Sc = cold allowable stress at Tmin
Sh = hot allowable stress at Tmax
Symin = derated yield stress at Tmin
Symax = derated yield stress at Tmax
Tmin = minimum temperature
Tmax = maximum temperature

Refer to ASME B31.8 Table 841.1.8-1 for the temperature derating factors. The derating factors are valid upto 232 C (450 F) only. For temperatures above 232 C (450 F) use material specific data. The derating factor is assumed to be valid for yield stress and tensile stress. Use the Result Table option to display a table of design stress versus material type.

Tool Input

syutype : Stress Schedule Type
mattype : Material Type
- SMYSu : User Defined SMYS Specified Minimum Yield Stress
- SMTSu : User Defined SMTS Specified Minimum Tensile Stress
tfactype : Temperature Factor Type
- Tu : User Defined Temperature Derating Factor
Td : Design Temperature

Tool Output

S : Design Stress (Sc or Sh)
SMTS : Specified Minimum Tensile Stress
SMYS : Specified Minimum Yield Stress
Su : Derated Tensile Stress
Sy : Derated Yield Stress
T : Temperature Derating Factor

CALCULATOR : ASME B31.8 Section 833.6 Longitudinal Stress Check [FREE] ±

Calculate longitudinal stress (ASME B31.8 section 833.6). For submerged pipe use the user defined external pressure option.

Tool Input

diamtype : Pipe Diameter Type
- Du : User Defined Outside Diameter
- du : User Defined Inside Diameter
petype : External Pressure Type
- Peu : User Defined External Pressure
sectype : Cross Section Type
- Zu : User Defined Pipe Z Modulus
- Axu : User Defined Pipe Cross Section Area
ifactype : Stress Factor Type
- iiu : User Defined In Plane Stress Factor
- iou : User Defined Out Of Plane Stress Factor
M : Design Moment
tn : Nominal Wall Thickness
Sy : Yield Stress At Maximum Temperature
Fx : Pipe Wall Axial Force
P : Internal Pressure

Tool Output

ΔP : Pressure Difference
Ax : Pipe Cross Section Area
D : Pipe Outside Diameter
D/tn : Pipe Diameter Over Wall Thickness Ratio
Pe : External Pressure
Rm : Pipe Mid Wall Radius
Sa : Allowable Longitudinal Stress
Sb : Bending Stress
Sl : Longitudinal Stress
Sl/Sa : Longitudinal Stress Over Allowable Stress Ratio (≤ 1)
Sp : Pressure End Cap Stress
Sx : Axial Stress
Z : Z Modulus
d : Pipe Inside Diameter
dm : Pipe Mid Wall Diameter
ii : In Plane Stress factor
io : Out Of Plane Stress factor

CALCULATOR : ASME B31.8 Section 833.8 Flexibility Stress Check [FREE] ±

Calculate expansion stress and allowable stress (ASME B31.8 section 833.8). For submerged pipe use the user defined external pressure option.

Tool Input

diamtype : Pipe Diameter Type
- Du : User Defined Outside Diameter
- du : User Defined Inside Diameter
petype : External Pressure Type
- Peu : User Defined External Pressure
sectype : Cross Section Type
- Zu : User Defined Pipe Z Modulus
- Axu : User Defined Pipe Cross Section Area
ifactype : Stress Factor Type
- iiu : User Defined In Plane Stress Factor
- iou : User Defined Out Of Plane Stress Factor
M : Design Moment
S : Design Stress
N : Number Of Cycles
tn : Nominal Wall Thickness
Fx : Pipe Wall Axial Force
P : Internal Pressure

Tool Output

ΔP : Pressure Difference
Ax : Pipe Cross Section Area
D : Pipe Outside Diameter
D/tn : Pipe Diameter Over Wall Thickness Ratio
Pe : External Pressure
Rm : Pipe Mid Wall Radius
Sa : Allowable Expansion Stress
Sb : Bending Stress
Se : Displacement Stress
Se/Sa : Displacement Stress Over Allowable Stress Ratio (≤ 1)
Sl : Longitudinal Stress
Sp : Pressure End Cap Stress
Sx : Axial Stress
Z : Z Modulus
d : Pipe Inside Diameter
dm : Pipe Mid Wall Diameter
f : Stress Range Factor
ii : In Plane Stress factor
io : Out Of Plane Stress factor

CALCULATOR : ASME B31.8 Section 841.1 Pipeline Longitudinal Weld Maximum Number Of Pressure Cycles [FREE] ±

Calculate the maximum allowable number of pressure cycles for the longitudinal weld joint (ASME B31.8 section 841.1.9). Evaluation of potential fatigue crack growth is recommended for pipelines which exceed the allowable number of full MAOP cycles.

Tool Input

syutype : Material Grade Type
mattype : Material Type
- SMYSu : User Defined SMYS Specified Minimum Yield Stress
ffactype : Design Factor Type
- Fu : User Defined Design Factor
tfactype : Temperature Factor Type
- Tu : User Defined Temperature Derating Factor
tn : Nominal Wall Thickness
tmax : Design Temperature

Tool Output

F : Design Factor
N : Allowable Number Of Cycles
SMYS : Specified Minimum Yield Stress
Sa : Allowable Stress
Sy : Derated Yield Stress
T : Temperature Derating Factor