Minimum wall thickness
ASME B31.3-2022 Process Piping · Para 304.1.2
Step 1 — Pipe size (ASME B36.10)
Select NPS and schedule above
Step 2 — Material allowable stress (ASME B31.3 Appendix A)
Select material and temperature above
Auto-filled (read only)
—
From ASME B36.10—
From ASME B31.3 Appendix AYour design inputs
Typically 1.0 for temp ≤ 950°F
0.4
Auto-filled from material & temperature
Typical: 1/16" to 1/8"
Typically 12.5% per ASTM
Results
Calculated min wall t
—
inches
With corrosion allowance
—
inches
Required (incl. mill tolerance)
—
inches — use for schedule selection
ASME B31.3 para 304.1.2:
t = (P × D) / (2 × (S × E × W + P × Y))Add corrosion:
t₁ = t + c · Mill tolerance: t_req = t₁ / (1 − mill% / 100)
Select a schedule where nominal wall ≥ t_required. Always verify against ASME B31.3 and confirm allowable stress from Appendix A at design temperature.
Pipe weight & section properties
Piping Handbook 7th Ed. (Nayyar) formulas
Select pipe size (ASME B36.10)
Select NPS and schedule above
Auto-filled (read only)
—
From ASME B36.10—
From ASME B36.10Your inputs
Water=1.0 · Crude oil≈0.85
Section properties
Inside diameter ID
—
inches
Metal area Am
—
in²
Flow area Ai
—
in²
Moment of inertia I
—
in⁴
Section modulus Z
—
in³
Radius of gyration r
—
inches
Weight
Pipe weight/ft
—
lb/ft
Fluid weight/ft
—
lb/ft
Total weight/ft
—
lb/ft
Pipe total
—
lb
Fluid total
—
lb
Grand total
—
lb
Piping Handbook 7th Ed. — Nayyar:
ID=OD−2t · Am=0.7854(OD²−ID²) · I=0.0491(OD⁴−ID⁴)Z=0.0982(OD⁴−ID⁴)/OD · Pipe wt/ft=10.6802×t×(OD−t)Fluid wt/ft=0.3405×ID²×SG
Verify pipe dimensions against ASME B36.10 or B36.19 before use in design.