Metal and non-metal straight-pipe wall thickness (GB/ASME); optional GB/T 17395 OD match notes; GB/T 20801.1-2025 appendix B allowable stress; schedule adequacy screening.
Design conditions
No.
Name
Code
Unit
Value
Notes or Formulas
01Design pressureP
01
Design pressure
P
Material
No.
Name
Code
Unit
Value
Notes or Formulas
02Allowable stressS
02
Allowable stress
S
03Joint efficiencyE
03
Joint efficiency
E
Pipe geometry
No.
Name
Code
Unit
Value
Notes or Formulas
04Outside diameterDo
04
Outside diameter
Do
05Temperature correction factorY
05
Temperature correction factor
Y
06Corrosion allowancec₁
06
Corrosion allowance
c₁
Results
No.
Name
Code
Unit
Value
Notes or Formulas
07Calculated walltm
07
Calculated wall
tm
tm = P × Do / (2 × (S × E + P × Y))
tm = P × Do / (2 × (S × E + P × Y))
08Design walltd
08
Design wall
td
09Standard series picktr
09
Standard series pick
tr
Rounded up to a common plate or pipe series; verify against procurement standards.
Rounded up to a common plate or pipe series; verify against procurement standards.
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Disclaimer
The calculation results provided by this tool are for reference only and should not be used as the sole basis for final engineering design. The developer is not responsible for any direct or indirect engineering losses caused by the calculation results.
Engineering guideAssumptions, standards & FAQ — tap heading to expand or collapse
What this wall-thickness page covers
Metal (GB thin cylinder or ASME B31.3 style) and non-metal modes. In GB mode, pick OD from GB/T 17395, interpolate [σ]ᵗ from appendix B, and auto-fill Y and W from material context; after calculation, NPS is inferred from OD and only schedules whose nominal wall meets design thickness T are listed (minimum adequate first), with φOD × wall in the note column.
Model assumptions
Straight pipe: thin-wall metal form as shown in the on-grid formula; non-metal replaces allowable stress times joint efficiency with allowable hoop stress times strength design factor. When calculated wall thickness reaches one-sixth of outside diameter, thick-wall or alternate code formulas may be required—see the on-grid warning.
GB mode: appendix B [σ]ᵗ, table 27 Y, and table 17 W are interpolated from published server data and shown read-only; ASME mode requires manual stress entry. Schedule screening lists only adequate options and is not a final procurement specification.
References & further reading
ASME B31.3 Process Piping — pressure design of components and branch reinforcement (per edition in force where you practice).
GB/T 20801.1-2025 (Pressure piping code — Part 1: Industrial piping) for thin-wall cylinder screening alignment where applicable.
Listing standards is for traceability only; it is not an endorsement and does not replace licensed engineering review.
Shareable URL
Use “Copy shareable link” below the grid; t=m or n selects metal/non-metal. All math stays in the browser.
Frequently asked questions
Can I use outputs on a stamped calculation submittal?
Only after your qualified engineer confirms inputs, code edition, and any items not modeled here.
Why might metal and non-metal give identical calculated wall for the same numbers?
When allowable hoop stress times strength design factor numerically matches allowable stress times joint efficiency, the thin-wall cylinder reduces to the same denominator pattern.
Why does schedule screening show only some schedules?
After design thickness T is calculated, NPS is inferred from OD and only schedules with nominal wall ≥ T are listed; the minimum adequate schedule is selected by default, with φOD × nominal wall in the note column.
Extended copy on this page (headings, assumptions, references, FAQs) may be drafted or localized with AI assistance; engineering judgment and governing codes still apply. Numerical models run locally in your browser as implemented. For contract-critical work, cite primary standards and qualified review.
