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Engineering reference

Units & Load Terminology

A short primer on the units and load terms used throughout this catalogue. Safe Working Loads and certification are always confirmed per project and per order — work to the certificate, not the catalogue.

Units Used in This Catalogue
Masst (tonne)
Masskg (kilogram)
Mass conversion1 t = 1 000 kg
ForcekN (kilonewton) — ≈ 9.81 kN per tonne of force (≈ 10 kN/t as a working rule)
Lengthmm — all dimensions in mm unless stated otherwise
Container lengthft — nominal ISO lengths: 10, 20, 40 and 45 ft
Angle° (degrees)
Load Terminology
SWL / WLLSafe Working Load / Working Load Limit — the maximum load a device may carry in normal service. Used interchangeably in this catalogue.
MBLMinimum Breaking Load — the load at which a device is expected to fail. Always well above the SWL.
Proof loadA test load above the SWL but below the MBL, applied to verify a device without damaging it.
Safety factorThe ratio MBL ÷ SWL. Lifting and lashing gear carries a margin (commonly 4× to 6×); the governing standard or certificate gives the exact figure for each item.