Why a 6 m tube does not fit in a 20GP, and what to do about it.

Nominal figures vary by box and operator; confirm with your forwarder before the loading plan is fixed.

The three workable plans

A 20GP with 5.8 m members is often cheaper per tonne than a 40HQ for a small order — but re-check the bay length.

The 12 m case

A 12 m tube fits a 40 foot box with about 30 mm of clearance each end, which is not enough for a careless load. Bundles are loaded diagonally or with the box's own end walls protected, and the last bundle is what usually damages. If 12 m members are specified, the loading plan is part of the quotation.

Weight is rarely the limit

A 1,000 m² multi-span frame at 6 kg/m² weighs about 6 t. Even a 12,000 m² project at the same rate is 72 t, which is three containers and still volume-limited. Heavy-wall tube and dense fittings are the exception: a container of Ø60.3×3.0 reaches payload before it fills.