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DRUMMING A NEW BEAT
Page 56
Page 57
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A Bristol operator has revolutionised minimix efficiency with a weighing system that allows pre-mix concrete to be delivered in multi-drop style. Geoff Ashcroft reports.
0 n-board weighing of pre-mix concrete at the point of delivery could be about to change the face of minimix operations forever.
So says Len Wright of Wright Minimix in Bristol, who has developed a means of making multiple drops from a single load of pre-mix concrete. It offers massive efficiency gains in the minimix market, where two or three traditional small-load deliveries can now be made in a single journey. Operating from Hanson's batching plant in Victoria Road, St Phillips, Bristol, he sought the solution as soaring demand for small-load deliveries put huge pressure on the truck fleet.
"I was faced with two options — either buy more trucks and find more good operators which is increasingly difficult, or improve the efficiency of what we had," explains Wright.
Already operating a fleet of seven mixer trucks with capacities of 3m or 4m' delivering about 25,000m' a year. Wright believed there were efficiency gains to be had from within the fleet.
"Having to return to the yard for the next small load of concrete proved desperately inefficient," he says."There had to be a way of going out fully loaded and making several deliveries from the same load."
With a few ideas. Wright turned to on-board weigh specialist PM Group and mixer firm Hymix in search of a solution.
The result is a drum and chassis assembly suspended on weigh cells to provide an accurate measurement of the load.The system uses four weigh cells on threeand four-cube mixers and six weigh cells on fiveand six-cube bodies.
Constant monitoring
Weighing is confirmed by an in-cab computer that allows the driver to give the customer an accurate delivery note relating to the amount of concrete discharged, while a screen at the rear of the machine by the drum's control panel enables constant monitoring of the load while discharging takes place.
-Only the drum and its frame are weighed — which are known weights — to provide a zero figure when the mixer is empty," explains Wright. "And the discharge chute stands separately on the chassis, to avoid weighing what's already left the drum. It's accurate to within 15kg, which is about a shovel-full of concrete."
Wright Minirnix has three systems installed on its fleet, at an additional cost of about £18,000 per truck, which includes a reversing camera system played through the in-cab computer screen, a hands-free phone kit and GPSbased satellite tracking. One is mounted to a three-cube. IS-tonne chassis and two others are in use on 26-tonne 6x2.310hp Iveco Cursor chassis— each 6x2 uses a lifting and steering rear axle, and carries a six-cube Hymix body.
A third 26-tonne outfit. using an Iveco Strafis chassis, is already on order and Wright has sold five such rigs to multi-national operator Hanson. "The 6x2s give massive efficiency gains," he says. "With a lift and steer rear axle, they are as manoeuvrable as a four-cube truck and will get anywhere that the smaller truck can. But they carry 50% more payload, which makes multidrop that much more efficient."
Wright adds that he would never have contemplated running a 26-tonner on minimix duty in urban areas without a lift and steer rear axle.
Productivity gain
In terms of productivity, he reckons the weighmixer trucks outperform the others on his fleet by an extra one to two loads per day, while travelling about 4,000km fewer each year.
"The productivity gain is about 15% for each truck," he says."And although we're probably using slightly more fuel carrying higher initial payloads, I expect our fuel bill to drop as we don't make as many empty trips back to the hatching plant to reload.
"Two 6x2s with on-board weighing can comfortably do the work of three conventional 4x2 minimix trucks," he adds.
These productivity claims are supported by the firm's profitability. In the 15 months that on-board weighing has been used by the firm,Wright says profits have increased by around 38%, while concrete sales have increased only marginally, at around 6%.
"It's all a direct result of increasing our operating efficiency," he says."We've not changed anything else.
An added bonus of the system is that if a customer has over-estimated and doesn't want the volume of concrete initially ordered, the on-board weighing allows Wright Minimix to charge an accurate disposal rate for handling the surplus concrete. And the system's accuracy also warns of any concrete that might be sticking in the drum.
Further efficiency gains can still be found, he reckons,in effective route planning to ensure trucks are not back-tracking. And the recent addition of satellite tracking to his fleet is expected to enhance the level of customer service already in place at Wright Minimix.
-On-board weighing now gives us the ability to weigh as little as 0.1m ," he says.
"For our customers, having a minimix delivery is now a cost-effective alternative to small volume collection." •