Two Open Decks, Two Different Specialities
The lowbed and the flatbed are the two basic tools of open-deck transport, and from a distance they look alike: neither has walls or a roof. Their design goals, however, are opposites. The flatbed is built to move standard-height general cargo quickly and economically; the lowbed is built to move tall, heavy machinery while staying within legal clearance limits.
Flatbed (Platform) Trailer
The flatbed is the simplest trailer type, offering a flat and relatively high loading deck.
- It serves a wide range of cargo: sheet packs, coils, profiles, precast elements, timber and containers.
- Loading is possible from the side, the rear and the top (by crane); lashing points allow flexible load layouts.
- Its structure is light and simple: low purchase price, high payload, cheap maintenance.
- Its limit appears in height: because of the deck height, a tall load on top can easily exceed the overall height limit.
Lowbed Trailer
The lowbed's reason for existing is its low loading well: between the axles, the chassis drops close to the ground.
- High-bodied machines such as excavators, dozers, rollers, cranes and agricultural machinery can be carried within the legal height limit thanks to the low well.
- Hydraulic rear ramps (or a detachable gooseneck) let a machine climb aboard under its own power; no crane is needed.
- Axle options from 2 to 8 and extendable chassis models keep the load per axle within legal limits for very heavy and long cargo.
- It comes at a price: a lowbed is heavier and more expensive than a flatbed, and its maintenance (because of the hydraulics) costs more. The well section is inefficient for standard palletised freight.
Decision Criteria
Three questions decide the choice:
- Cargo height: if cargo height plus deck height exceeds the legal limit, a lowbed is mandatory; if not, the flatbed is the economical option.
- Does the cargo have its own wheels or tracks? Machines that can climb a ramp under their own power load onto a lowbed without a crane; standard loads placed by crane are handled faster on a flatbed.
- Trip profile: an operation that constantly moves machinery pays off the lowbed investment; for a fleet that carries tall loads only occasionally, a rented lowbed plus owned flatbeds is usually more efficient.
A Note on Clearances and Permits
In lowbed transport the load often approaches "exceptional transport" limits. Where width, height or axle-load limits are exceeded, a route permit is required; a well-planned lowbed operation builds the permit cost and lead time into the freight calculation from the start.
Barlas Trailer manufactures standard, extendable and well-type lowbed models as well as flatbed trailers.