ASME B31.4 Pipeline Wall Thickness & Span Calculator (Excel Dashboard)

Description
Built on ASME B31.4's pressure-design equation for liquid and slurry pipelines: S = 0.72 × E × SMYS, tp = P·Do / 2S (para 402.3.1(a) and 404.1.2).
Enter design pressure, pipe inside diameter, trial wall thickness, corrosion allowance and mill tolerance, then pick a pipe grade — 12 built in (ASTM A106/A53, API 5L B through X70, JIS SS400, SS 304/316) or custom SMYS/UTS — and a weld joint type. Material strength and joint factor resolve automatically.
Three KPI cards give the verdict at a glance:
• Wall thickness check — PASS/FAIL against required nominal thickness
• Governing max span — bending-stress support span limit
• Collapse pressure rating — external collapse pressure (thin-shell)
How to use:
1. Enter pressure and pipe geometry in the blue input cells (bar, mm, %).
2. Pick the pipe grade and weld joint type, or type custom SMYS, UTS and joint factor E.
3. Read the three KPI cards. The calculation trail underneath shows allowable stress, pressure design thickness, required nominal thickness and margin, so a checker can follow it line by line.
Typical use: quick sizing checks for crude, refined products, water and slurry lines, design reviews, and sanity-checking vendor calculations.
Limitations: the weld joint factor (E) uses common reference categories, not a full spec-by-spec table. Span and collapse checks are general engineering estimates. Preliminary design verification only — final design must be reviewed by a qualified engineer against the current ASME B31.4 edition. Not affiliated with or endorsed by ASME.