Calculation Mode:

Max Pressure Burn-Through Risk Welding Recs

Pipe Specifications

Pipe OD

Wall Thickness

Min 0.188" per API RP 2201

Branch Connection OD

Enter 0 if no branch

Material & Design Code

Pipe Material

Design Code / Location ClassDetermines design factor (F)

Operating Conditions

Operating Temperature

°F

Affects temp derating (T)

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Comprehensive guide to WPS/PQR qualification, burn-through prevention, and ASME B31.8/API 1104 standards.

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Key Formulas

P_max = (2 × S × F × T × t) / D

P_max = Max Allowable Pressure

S = SMYS (psi)

F = Design Factor (0.4-0.72)

T = Temp Derating Factor

t = Wall Thickness (in)

D = Outside Diameter (in)

HI = (V × A × 60) / (TS × 1000)

HI = Heat Input (kJ/in)

V = Arc Voltage (V)

A = Current (Amps)

TS = Travel Speed (in/min)

Standards & References

API RP 2201
Safe Hot Tapping Practices - Min wall 0.188", stress limits
ASME B31.8
Gas Transmission - Design factors by location class (F = 0.4-0.72)
ASME B31.4
Liquid Pipelines - Design factor F = 0.72
API 1104
Pipeline Welding - WPS qualification, welder certification
ASME Section IX
Welding Qualifications - PQR/WPQ requirements

Critical Safety Notes

Min Wall: 0.188" absolute minimum, 0.250" recommended per API RP 2201.
Heat Input: Limit to 25-35 kJ/in to prevent burn-through on pressurized pipe.
UT Required: Verify actual wall thickness by ultrasonic testing before welding.
Low-H Electrodes: E7018 or equivalent low-hydrogen electrodes only.
Electrode Storage: Maintain at 250-300°F in heated rod oven.
Welder Qualification: Per ASME Section IX or API 1104 on similar joint.

Heat Input Limits by Wall Thickness

Wall (in)	Max HI (kJ/in)
< 0.188"	12 (Not rec.)
0.188" - 0.250"	20
0.250" - 0.312"	25
0.312" - 0.375"	30
0.375" - 0.500"	35
> 0.500"	40

Hot Taps & Welding Toolkit

Pipe Specifications

Material & Design Code

Operating Conditions

Burn-Through Assessment

Heat Input Calculator

WPS Parameters

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Max Operating Pressure

Burn-Through Risk Assessment

WPS Recommendations

Key Formulas

Standards & References

Critical Safety Notes

Heat Input Limits by Wall Thickness

Hot Taps & Welding Toolkit

Pipe Specifications

Material & Design Code

Operating Conditions

Burn-Through Assessment

Heat Input Calculator

WPS Parameters

📚 Learn the Theory

Max Operating Pressure

Burn-Through Risk Assessment

WPS Recommendations

Key Formulas

Standards & References

Critical Safety Notes

Heat Input Limits by Wall Thickness

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