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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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Jul 16, 2026
Mechanical Seals: How Spinning Shafts Stop Leaks
See how flat seal faces control leakage around a rotating pump shaft, manage pressure and heat, and reveal the causes of failure.
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Jul 15, 2026
Couplings: Joining Two Shafts That Do Not Line Up Perfectly
See how shaft couplings transmit torque, tolerate small alignment errors, protect machinery, and reveal trouble before expensive parts fail.
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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 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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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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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.
Calculator ready
Weekly Planner
Plan engineering work, review priorities, and keep schedules connected to your EnggTools account.
Planner ready
Bolt Torque Calculator
Calculate bolt torque, pretension, preload scatter, retained clamp, pressure-opening checks, and structural slip checks.
Calculator ready
Engineering Articles
Original practical guides, calculation explanations, and engineering judgment notes.
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Standards Explained
Plain-language summaries of industrial standards without reproducing protected code text.
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Study Resources
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