About flooring
1: What is the ideal surface for operating air cushions?
The surface should be air-tight to ensure that the toric envelope located between the load and the floor can be inflated to form an air cushion.
The surface should be smooth in order to maintain a fluid film between the toric envelope and the floor with a minimum amount of air. Near frictionless movement can be obtained on this fluid film.
The surface should also be flat and slope free so as to prevent the load from sliding on this low friction fluid film.
2: According to which DIN standards does new factory flooring need to be laid?
New factory flooring for transportation using a fluid film should be laid in accordance with allowances for flatness, as set out in DIN 18202 standard, section 5, line 4.
The surface should be smoothed over, then covered by a sealer and eventually given an epoxy coating.
You can simply follow our floor specifications.
See document Air cushion floor specifications / Spécification des sols
3: Are there any specific requirements for expansion joints?
Expansion joints should be filled with an elastic compound. We recommend a rubber-like urethane with a Shore-index of approximately 94. To ensure that the joint can be filled properly, a width of no less than approximately 10mm is recommended. Air loss is minimal when the filter is slightly curved upwards.
4: How smooth should the floor surface be?
The smoothness of the surface has a major influence on air consumption. The rougher the surface, the more air is needed to maintain the air film. On a rough, sandpaper-like surface increased friction can cause more wear and tear on the air cushion material.
5: How are floor condition and air consumption linked?
The required air volume required to move a specific load, on different surfaces with various friction levels, can be determined using the index table here below. The standard reference Index No. 1 applies for a polished plate glass surface. Index No. 3, for example, means that air consumption will be multiplied by three.
| Surface Description |
Index Number |
| Polished plate glass |
1 |
| Smooth, machine polished, sealed concrete |
2 |
| Smooth Epoxy coating |
1 – 2 |
| Vinyl Tile (well laid) |
1.5 – 2 |
| Galvanised sheet |
1.5 – 2 |
| Hot-rolled sheet or plate |
1 – 2 |
| Varnished hardwood panels |
1 – 2 |
6: What is the specific weight of the load borne on flooring?
The specific load borne on flooring when using air cushions is low, due to their wider surface, flexibility and reduced net weight, in contrast to wheeled vehicles. Delicate surfaces such as parquet, linoleum, varnished hardwood or surfaces with floor heating can support heavy loads on air cushions without risk of damage. Although the floor load permitted must be respected, air cushions still provide major benefits.
7: Does flooring need to be sealed?
Air escaping through a non air-tight floor can result in air cushions not being able to build enough pressure to carry the load or even maintain an air film to float on. A non-sealed concrete floor is porous and allows small amounts of air to escape. Also, sealed surfaces can “leak” through cracks, blisters, scaling or joints. These can easily be repaired with filler, tape or overlays.
8: Can air cushions be used on old flooring?
Floors for transportation using a fluid film should be laid in accordance with allowances for flatness as per DIN 18202 standard. In order to reach these requirements, it may be necessary to cover the floor with a concrete coating. To ensure that this coating adheres properly to old flooring, the old surface may need to be scrubbed with a blow-torch, ground or polished beforehand.
One-off moves, such as relocating machines, can be done on practically every surface by covering the track with sheet metal overlays.
9: What if the floor is undulated or has slopes?
Due to their flexibility air bearings will comply to undulations with height differences up to 2% of the air cushion diameter. Large undulations can be considered as slopes. Due to reduced friction a load on air film will go down the slope. The force needed to redirect a load on a slope can be calculated as follows:
F = tg a. G
In similar cases the load must be secured by means of Bertin Technologies drives or other mechanical systems.
Steps can be negotiated by means of a ramp. In this last case, the above mentioned values must be considered.
10: Can air cushions work on dirty floors?
For a flawless and lasting operation of air bearings a clean floor is needed. On a well-prepared surface wear is almost non-existent. Small objects like sand grains, wood chippings, cigarette butts etc. will be blown away by the escaping air film. Paint stains, oil stains, truck tire marks etc. will impair the surface quality, stick to the air cushion torus and increase the air consumption. Large and sharp objects such as nails, screws or steel chippings stuck on the floor will damage the torus and should be removed.
11: Can an air cushion cross gaps?
Most of air cushions will lose too much pressure when crossing a gap and will not be able to function properly.
The Bertin Technologies Double Stage Air Cushions however will, within certain limits, be able to cross gaps.
12: How can one stop the system sliding on when used on unsmooth flooring?
A guide wheel can be installed to keep the system on a certain course and stop it sliding away.