The dolly: (Dolly sits between the gooseneck and low bed)
A dolly is designed to sit between the gooseneck and the lowbed. This the loading capacity and also the loading floor. This last point is unique to a Broshuis pendle axle low loader This is because the dolly can be used to support the load. Thanks to the dolly the weight is better distributed between the neck and rear bogie. This configuration allows the operator to carry a bigger and diverse loads. The Dolly comes in two variants, a fixed dolly on the neck, or a removable dolly.
Removable dolly
Advantages
+ Normal coupling height gooseneck
+ Low loader can be used without dolly
+ Standard truck
+ Permitted bogie load at least 12T/line
+ Lighter low bed
+ Easy to operated
+ Dolly axles liftable
+ Auxiliary steering on all axles of the low loader
+ Can be converted to a semi low loader
+ Possible to link more axle lines
Disadvantages
- Longer combination
- Higher tare weight combination
- Larger turning circle
- Higher “cost of ownership”
- Higher purchase value
- Operation requires experience
- More complex hydraulic, air and electrical systems
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LOW LOADER
The loading floor of a low loader is "recessed" in relation to the bogie height. This enables the operator to transport high loads with clearance under bridges and tunnels.
PAYLOAD
If you want to increase the trailer payload you would normally add additional axles under the loading floor, but with a low loader this is not a practical solution with the lowered deck. The solution would be to add extra axles to the rear bogie, but this limited to 3 axle low loader because of the weight distribution between king pin and rear bogie.
WEIGHT DISTRIBUTION
If more axles are added to the rear bogie the low loader will become heavier and only gets more payload at the back. Therefore the centre of gravity of the load will move towards the rear bogie.
To achieve this axles should be added both at the front and rear to increase the trailer capacity and correctly position the centre of gravity,
To do this the chassis would also require strengthening.
LOAD CAPACITY
There is only one way to increase the loading capacity at the rear, that is to add additional axles, which means more steel and extra weight.
There are four options for increasing the load capacity at the front of the loading floor, each with its own advantages and disadvanges. The ‘’multi axle truck’’, the Jeep Dolly, the Fixed dolly at neck and a Removable dolly
