Skids and bases
Machinery skids and transport bases
A skid or base spreads a machine’s weight and gives the lashings somewhere to hold. On a 40′ flat rack it matters: a load on 6 ft 7 in (2 m) of the beams takes 56,400 lb (25.6 t) against 54 US tons (49.1 t) over the full length, and beams can lengthen the footprint by up to 3 ft 3 in (1 m) at each end[1].
- what a 40′ high cube flat rack takes on a 6 ft 7 in (2 m) resting length[1]
- 56,400 lb25,600 kg
- the same rack with the load over its full length[2]
- 54 US tons49,100 kg
- that beams may extend the footprint at each end[1]
- 3 ft 3 in1 m
- core temperature for ISPM 15 heat treatment of skid timber, for 30 minutes[3]
- 56 °C
Why the footprint matters
The rated payload assumes the load bears on the whole length of the main beams. Half the rated payload may be loaded on any footprint[1].
| Resting length | Payload[1] |
|---|---|
| 6 ft 7 in (2 m) | 56,400 lb (25.6 t) |
| 19 ft 8 in (6 m) | 72,100 lb (32.7 t) |
| 32 ft 10 in (10 m) | 92,800 lb (42.1 t) |
| 39 ft 4 in (12 m) | 54 US tons (49.1 t) |
Skid, base or neither
| Method | Use it when | Avoid it when |
|---|---|---|
| Timber skid | Machines without wheels or tracks, such as compressors, generators and pumps, moved by forklift. | The piece is heavy enough to crush timber at its feet: a steel base spreads it better. |
| Steel base or beams | Heavy pieces with a short footprint on a flat rack, to spread the weight along the main beams[1]. | The piece already rests on the full rack length. |
| None | Machines on tracks or wheels that sit on bedding across the main beams[4]. | Point loads such as outriggers or feet sit on the floor. |
How a base is made
Rules that apply
- ISPM 15 wood packagingIPPC, administered in the U.S. by USDA APHIS
Wood packaging and dunnage must be heat-treated to a core temperature of 56 °C for at least 30 minutes, or fumigated, and carry the IPPC mark with the US country code, the facility number and HT or MB. Marked wood can be reused; repaired or remanufactured wood must be treated and marked again.[3]
Applies to: Crates, skids, blocking and dunnage
- SOLAS verified gross mass (VGM)IMO
Since 1 July 2016 the shipper must give a signed verified gross mass for each packed container, found by weighing the packed unit or by adding the weighed cargo, lashing and dunnage to the container tare. The carrier needs it before the stowage plan is drawn up; without it the container is not loaded.[5]
Applies to: Every packed container, flat rack and open top
- Cargo securement on trucks (49 CFR 393.106 and 393.130)FMCSA
The tiedowns on a load must together have a working load limit of at least half its weight. A machine on wheels or tracks weighing 10,000 lb or more needs at least four tiedowns, fixed as close as practicable to its front and rear or to its designed tie points; buckets and shovels are lowered and secured, and articulated machines are locked so they cannot articulate.[6][7]
Applies to: Machines on wheels or tracks moved by truck, and every other load on a public road
Questions about skids and bases
Why does a heavy machine need a base on a flat rack?
Because a flat rack’s payload falls when the load sits on a short length of its beams. On 6 ft 7 in (2 m) a 40′ rack takes 56,400 lb (25.6 t), about half its rating; beams that spread the load restore part of it.
Can a skid be reused?
Steel bases can. ISPM 15 marked timber can be reused too, but repaired or remanufactured wood must be treated and marked again.
Is a base included in the VGM?
Yes. The verified gross mass includes the cargo, its packing and securing material, and the container or rack tare.
Sources
Every figure on this page comes from the documents below, each checked on the date shown. Carriers and authorities revise them, so we confirm the current figure when we book.
- [1]Hapag-Lloyd, Weight distribution in containers for safe transport (guideline), checked October 18, 2026
- [2]Hapag-Lloyd, 40′ High Cube Flatrack, checked October 18, 2026
- [3]USDA APHIS, Export ISPM 15-compliant wood packaging material, checked October 18, 2026
- [4]Hapag-Lloyd, A Guide for the Loading and Lashing of Cargo on Hapag-Lloyd Flatracks, checked October 18, 2026
- [5]IMO, SOLAS verified gross mass requirement enters into force (1 July 2016), checked October 18, 2026
- [6]eCFR, 49 CFR 393.106 General requirements for securing articles of cargo, checked October 18, 2026
- [7]eCFR, 49 CFR 393.130 Securement of heavy vehicles, equipment and machinery, checked October 18, 2026
Send us the machine and the destination
Give us the model or the measured dimensions and weight. We come back with the method, the sailing and a price, and the figures behind them.