On-board weighing improves efficiency

New on-board weighing system brings improved accuracy and cycle times to load-out operations at Eysey Manor Quarry.

A quarry's load-out operation is its main interface with customers on a day-to-day basis. Gains in efficiency here are not only important to site profitability but also to frontline customer service.

UK-based 1539 Raymond Brown Group is seeing a reduction in load-out cycle times at Eysey Manor Quarry after investing in a 380 Loadrite on-board scale for a new 395 Caterpillar 962H wheeled loader.

The Express scale offers high level weighing accuracy, regardless of lift speed and loader movement, through a complex combination of multiple-point triggering, speed compensation and dual pressure measurement.

Accuracy is 1+ACU-, helping the operator to load trucks to the correct value first time, reducing truck turnarounds at the weighbridge, eliminating the cost of double-handling of material, and avoiding overload fines.

Ian Wardall, quarry manager at Eysey Manor, said, "We have seen a downward trend in load-out cycle time since the Loadrite scale was introduced. Trucks are spending less time on site, using less energy and fuel, so hauliers are noticing the difference too. Achieving correct load first time is obviously very important when we get busy, allowing us to send trucks out sooner and keep queues down."

Raymond Brown Minerals and Recycling operates Eysey Manor quarry near Swindon under contract to 868 Tarmac Southern. It extracts and processes around 170,000tonnes of gravel annually, producing sharp sand and four grades of stone mainly for Tarmac's own use, including production of ready mixed concrete. The site runs two Caterpillar 962H wheeled loaders, including the new machine, as well as a 6512 Hitachi 210 excavator and Caterpillar D6 dozer working on landfill.

Wardall said, "About two thirds of trucks we load are 44tonne artics with a tolerance of 500kg. If you are loading with a 5 to 6tonne bucket and the scale is out by, say, 100kg on each bucket, you will end up over or under the permissible load." He estimates that accuracy levels overall are up from 85-90+ACU- within acceptable limits to 95-99+ACU- with the new scale. Quicker start-up times are making a difference too.

"We can spend half an hour each morning recalibrating the scales on existing machines while the hydraulic pressures build", - observed Wardall. "Set up with the Loadrite system is about ten minutes. If the quarry is very busy first thing, we can establish cycle times much quicker."

The technology weighs instantaneously and maintains accuracy across a wide range of operating parameters, according to Julian Athawes of 1541 Halomec, Loadrite's mainland UK distributor. He said, "Loading can be speeded up without loss of accuracy while in-built alarms keep the operation within desirable parameters."

Halomec is providing Eysey Manor with on-going service support. The scale was initially supplied and installed by 3006 Finning UK which has an arrangement to spec Loadrite systems as optional equipment on new Cats.

Although the Loadrite system is packed with features and functionality, it is proving surprisingly simple to use. "Our operators have had no real problems in getting to grips with the new scale. It's a very straightforward system, not that different to others we have used," said Wardall.

Halomec has spent time configuring the scale to suit the specific operational parameters of the quarry. As well as sand and gravel, they also handle a number of crushed stone products and recycled asphalt. Although not yet needed at Eysey Manor, the Express system has in-built data management and reporting features that can be configured to assist inventory and productivity management.

Wardall added, "As we get established with the technology, we will be looking to use more of its capabilities." Raymond Brown Group has bought Express scales for a Caterpillar 962H and 966H at two other sites within its minerals and recycling division.

Although it is early days with Loadrite's technology, long-term the group also expects to see cost savings in fuel, tyres, plant wear and tear per tonne of material loaded out, as well as increased customer satisfaction by getting more loads 'right first time' at the weighbridge.