Corrections log
Errors corrected in articles, calculators and lookup tables, listed by date. Typos and wording edits are not listed.
- — Technical Japanese #07 — safety signs: The 危険/警告/注意 level table was wrongly attributed to JIS Z 9101. JIS Z 9101 covers the colours and shapes of safety signs, not these signal words. The wrong reference has been removed.
- — Technical Japanese #17 — drawings & tolerances: The diameter symbol ⌀ was listed together with the geometric tolerance symbols ◎ ⊥ ∥. It has been removed from that list.
- — Technical Japanese #20 — abbreviations: The QCD row in the Vietnamese and Japanese versions read "SQD/QCD — safety, quality, delivery", which did not match its example. QCD is quality, cost, delivery. Both versions have been corrected.
- — All calculators: All 41 calculators were re-checked against JIS and Japanese manufacturers' technical data, using their worked examples; thresholds without a source were removed. The entries dated 4–5 Oct are the points that gave wrong results.
- — Assembly example: horizontal ball-screw axis: The axial load for the buckling check used only μ·m·g and missed the inertia force m·α (40 kg at 1.5 m/s²: 19.6 N instead of 79.6 N). Now uses THK's six-phase method.
- — Assembly example: vertical Z-axis lift: The axial load used only m·g, missing m·α during upward acceleration and the resisting force; motor torque ignored nut preload and rotor inertia. Corrected per THK and Oriental Motor.
- — Enclosure thermal calculation: Fan airflow had no safety factor (Sf = 2 per Oriental Motor), so it came out almost half too low; when outside air was hotter than inside, the result was meaningless. Corrected per TECTA and Oriental Motor.
- — Compression spring: Static loads were also multiplied by the stress correction factor κ. Under JIS B 2704-1, static loads use the uncorrected stress τ₀; only repeated loads use κ·τ₀. Corrected, with the missing JIS checks added.
- — Bolt torque ↔ clamp force: Property class 8.8 always used a yield strength of 640 N/mm²; above M16 it is 660 N/mm². Corrected per MISUMI, with a yield clamp-force check per JIS B 1083.
- — Utilities & capacity: The worked example stated that a Ø32 cylinder (12 mm rod, 100 mm stroke) at 0.5 MPa uses 1.71 NL per cycle; the correct figure is 0.89 NL.
- — Timechart: The device-conflict check missed a long step overlapping a non-adjacent one (e.g. A 0–10 s and C 3–4 s with B 1–2 s between). It now reports every overlapping pair.
- — I/O list: A start address invalid in the chosen base was misread silently ("18" in octal became X1), and Omron CP1E/CP1L were numbered as 16-bit units. Validation and the CP1 convention have been added.
- — Cross-roller ring: The equivalent load added the axial load directly without X, Y factors, so in THK's example the life came out about 70 % too low; the static safety factor also used the dynamic load. Corrected per THK.
- — Bearing life: The static safety factor fs was computed from the dynamic equivalent load P instead of the static equivalent load P₀. Corrected per NSK; P is now derived from Fr and Fa (JIS B 1518).
- — Parallel key: The key-size table returned 20×12 for every shaft above 65 mm (correct: φ80 → 22×14, φ120 → 32×18) and gave no keyway depths t₁, t₂. Corrected per JIS B 1301.
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