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Articles
Jul 11, 2026
Section Weight Calculator Math: From Profile Area and Density to Mass
Learn how solid, hollow, built-up, custom, and DXF profile areas become kg/m, lb/ft, and total member mass, with formulas, unit checks, and a worked steel RHS example.
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Jun 12, 2026
1D Linear Tolerance Stackup: Will the Parts Fit in the Envelope?
Will the parts always fit in the envelope? Worst-case and RSS methods for 1D chains, with the sign conventions that prevent the most common stackup errors.
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Jun 12, 2026
Datum Shift and Bonus Tolerance: How Much Positional Budget Do You Really Have?
A 0.02 position callout at MMC can really give you 0.05. How stated tolerance, bonus, and datum shift add up - and when not to trust the sum.
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Standards
Jul 10, 2026
ASME B31.3 Pipe Wall, Bend Thickness, Hoop Stress, and Hydrotest: A Beginner's Guide
A step-by-step beginner's guide to every B31.3 calculator input, straight and bend wall equation, temperature factor, hoop-stress utilization, hydrotest check, MAWP result, and warning, with a complete TP316 worked example.
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Jun 14, 2026
API 6A Made Simple: How to Build Wellhead Equipment That Passes
A plain-language walkthrough of API Spec 6A — how pressure testing, material selection, and fastener choices come together to make wellhead and tree equipment safe and compliant. Written so a beginner can actually follow it.
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Jun 29, 2026
API Specification 17D Explained: Subsea Wellhead and Tree Equipment
A plain-language, image-supported guide to API Specification 17D: what it covers, which subsea equipment uses it, how PSL and validation fit together, and what the pressure testing requirements mean in practice.
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ASME B31.3 Pipe and Tubing Calculator
Calculate thin-wall pipe thickness, hoop stress, finished bend wall and available bend thinning with B36.10/B36.19 dimensions and B31.3 references.
Code-referenced calculator ready
Land Area Calculator
Calculate irregular plot area from side lengths and the required diagonals for triangle-based land measurement.
Calculator ready
Indian Land Area Converter
Convert Gaj, Acre, Hectare, Cent, Guntha, Kanal, Marla, Bigha, Katha, Dhur, and other Indian land units.
Converter ready
Steel Section Sizes
Browse structural steel section size tables for I beams, H beams, channels, angles, bars, hollow sections, plates, sheet piles, and purlins.
Section tables ready
Section Weight Calculator
Calculate material weight per metre, foot, or inch from predefined sections, custom drawn profiles, or uploaded DXF geometry.
Drawing and DXF calculator ready
Tolerance Stackup Calculator
Calculate tolerance stackup, worst-case limits, RSS variation, fit risk, and assembly limits with clear assumptions and saved projects.
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Weekly Planner
Plan engineering work, review priorities, and keep schedules connected to your EnggTools account.
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Bolt Torque Calculator
Calculate bolt torque, pretension, preload scatter, retained clamp, pressure-opening checks, and structural slip checks.
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