TRAILER manufacturer Bradley Doublelock has pioneered a new design to overcome the growing problems associated with unevenly distributed loads on small plant trailers.
The Sentinel Plant Trailer and Load Management System, developed in conjunction with McNicholas plc and A-Plant, is designed to overcome issues such as overloading on both the front axle and the hitch.
Andy Spencer, sales director at Bradley Doublelock, said: 'The first problem is axle overloading, caused by a mismatch in towing heights between towing vehicles and plant trailers.
This problem has been exacerbated by a continuing reduction in the height of van hitches.' He added: 'The traditional configuration of axles on plant trailers is of two separate axles fixed rigidly to the underside of the trailer. As these two axles are very close, you only need to change the height very slightly to overload the front axle.' According to Mr Spencer the new trailer seeks to overcome the difficulties this creates by incorporating both axles in a bogey arrangement that allows them to rotate according to the distribution of the load.
The second problem is that of overloading the hitch, caused by simply placing the excavator too far forward on the trailer.
Mr Spencer explained: 'Vans are type-approved to have a maximum nose load of around 100 kg. Putting an excavator too far forward can create loads of up to 400 kg.' Bradley's response has been to install an electronic weight management device in the coupling. As the digger tracks onto the trailer it triggers a sensor.
This emits an intermittent bleep that speeds up as the excavator approaches the lower safe nose-load threshold. Once this is reached the noise ceases. But if the machine is moved too far forward a constant noise warns the driver to reverse.
The first Sentinel trailer, designed for 1.5-tonne excavators, is now in production and will be officially unveiled at the SED show next month. Further models are currently undergoing trials.