The Lehnhoff Variolock Fully Automatic Quick Coupler is at the start of a lifelong attachment with its new owners. Construction Plant News Editor, Lee Jones visits the BP Mitchell site.
When Brendan Mitchell struck out in 1990 with just a single truck the site clearance business was a very different proposition. In that time the process of disposing and processing construction waste has changed almost as much as the company that bears his name.
Today, the most recent addition to his considerable arsenal of equipment, the Lehnhoff Variolock fully automatic quick hitch system, is just one cog in a huge range of machinery.
In fact, from those humble beginnings Brendan can now call upon a fleet of 80 trucks, whilst a diverse range of services now includes not just site clearance, but demolition, ready mix concrete, concrete pumping and skip hire. In addition, the company has a flourishing business in transforming the detritus it brings in by the lorry load into aggregate material.
“If you go back more than ten years we were tipping most of our waste into landfill”, explains Brendan. “That’s just no longer deemed acceptable and 90 per cent of the waste that BP Mitchell clears from sites is now recycled – in fact it’s only really the clay-based material that we can’t rework into a useable product.”
Waste is now very much a commodity, with a value in its own right and, in transforming a 33 tonne Volvo 300D into a true multi-tasker, the Lehnhof Variolock is ably demonstrating that very point.
With this German-made system this machine’s operator is able to sort and process demolition waste by quickly interchanging between breaker, grab, bucket and magnet.
It is a part of a finely tuned operation that takes in the hardcore and concrete from demolition, as well as washable soils, and sees 6F2 Recycled Capping, Type 1 Sub-base, 40mm, 20mm and 10mm washed material, and sharp sand leave its gates in considerable volumes.
So why did Brendan make the initial investment and how does he view the benefits? “I had seen various other people using fully hydraulic quick hitch systems on demolition jobs, but it was at Hillhead where I started to do some serious research,” he recalls.
“Being new to the product I had a lot of questions to ask and the guys on the Worsley Plant stand couldn’t have been more helpful. Obviously my initial motivation was to improve on the time it takes to change attachments, but that’s not the only consideration.
“This is a tough environment for men and machines and the cost incurred in damage to hoses and pipework has been criminal for us, as has operators using the wrong tool for the job rather than go to the trouble of changing. With the Vario Lock the driver doesn’t even have to get out of the cab, and when you’re on a busy site where everything from tippers to wheel loaders and 360° excavators are on the move that has a significant impact on safety.”
At the time of our visit the Lehnhoff system had been in operation at BP Mitchell for just two weeks and the process of installation is as straightforward as it is in use. Most of the manufacturer’s systems can be fitted at the customer’s site, although this does depend on their attachments.
Adapter plates are bolted on to each attachment to be used with the quick coupler, and then hosed up accordingly. In BP Mitchell’s case the bucket had to go to the workshop to have the ears cut off and to have a Lehnhoff adapter plate welded on. The other attachments – in this instance a Bucket, Grab, Hammer, and Magnet – had the adapter plates fitted on site.
For the excavator, the fitter needs to remove the original quick hitch circuit (if it has one) and fit the Lehnhoff system, and the hitch is then fitted to the end of the excavator arm.
Once the system is fitted, it is tested and the pressures checked. The engineer will then conduct driver training on the system to ensure the end user is competent in using it. Where the BP Mitchell fitting took a day and a half the timescale is wholly dependent on the number of attachments, but a day or two is typical.
“Once fitted, it gives the operator much greater scope in terms of the tasks he can perform,” continues Brendan. “He can load the crusher, and sort and take away the steel rebar, and we’re finding it so much more productive than what we had previously.
“Just changing over all of the pipes from one tool to another is a time-consuming and dirty job, so the operators love this as the alternative. It certainly something that I would want on a demolition job because you are changing attachments so much in that kind of work. It’s early days yet but I could certainly see myself investing in more Lehnhof equipment.”
The fully automatic changing of attachments with Variolock gives the user a variety of benefits:
- Each attachment is ready for safe use in a matter of seconds
- Increased efficiency by saving time and manpower
- More efficient working – tool changes are viable even for short working cycles
- Cutting costs by treating machinery, attachments and hydraulic hoses with care
- More safety and comfort for the operator
- Only one adapter size for 19-40 ton machines
- Less contamination of the hydraulic system – environmentally friendly
- Unrestricted oil flow – less back pressure, less fuel consumption and lower oil temperature
- Unique BID system meaning less pipe work, very low excavator interruption
- Very easy to clean and maintain
For further information on the Lehnhoff Variolock Fully Automatic Quick Coupler, distributed in the UK by Worsley Plant, click here.
