Digital cells futureproof weighbridge installation

Edited by the Engineeringtalk editorial team May 17, 2006

Digital load cells are used in a 50 tonne Eurodeck pit-mounted weighbridge recently supplied to leading tyre processor Sapphire Energy Recovery.

Weightron Bilanciai has recently supplied a fourth 50 tonne Eurodeck pit-mounted weighbridge to leading tyre processor Sapphire Energy Recovery.

This latest weighbridge, measuring 18 x 3.2m, has been installed at the company's new processing plant in Manchester.

Sapphire Energy Recovery was formed in 2001 as a joint venture between Lafarge Cement UK and Michelin Tyre plc to recover and process "end of life" tyres for their use as cement kiln fuel.

It is estimated that over 40 million used tyres need recycling each year and since 2003 tyres can no longer be sent to land fill.

Their almost indestructible design, so vital when in use, makes them difficult to recycle, presenting a major problem for manufacturers and suppliers.

Although there are a number of processes for recycling the tyres for use in other products, this only prolongs the inevitable disposal problem.

By contrast, the Sapphire process provides a sustainable solution, where the inherent energy in the tyres is used to provide heat as part of the cement making process, with the tyres' steel properties absorbed into part of the cement.

The tyres are effectively fully consumed during the energy recovery process and there is no waste.

Sapphire organise the tyre collection from sources including retailers, manufacturers and used tyre stores, delivering them to one of their four processing centres strategically located across the UK.

The weighbridge, which is connected to a D410 weight indicator fitted with an MPP Flash memory card, is linked to Sapphire's own PC based Isis software system.

The memory card is approved by Weights and Measures and removes the need for a local printer.

For this installation the company decided on CPD digital load cells.

This technology brings important benefits to such applications, ensuring a future proof installation.

One of the key benefits offered by digital load cells is the ease of system calibration.

Unlike standard analogue installations, where the outputs from the load cells are summed arithmetically together, each CPD acts as its own reference centre, retaining critical calibration data.

Checking the "health" of individual digital load cells can be carried out either locally or remotely.

In the unlikely event of problems or damage, load cells can be replaced without the need to rerun cable, simply by unscrewing the waterproof connector and replacing the new load cell programmed with the relevant calibration data.

The robust IP68 design features of the CPD include laser welded stainless steel construction and a high integrity glass to metal sealed connector.

The ground straps, transient isolation disc and internal electronic surge protection devices protect the load cell from surge and lightning damage.

Sapphire's head of sales and marketing Ryan Mifflin is delighted with the latest installation and as he concludes: "Weighing incoming and outgoing vehicles provides crucial fiscal and legislative information at our plants".

"As a result reliability and accuracy of weight data is essential to the overall process".

"We have built up a strong working relationship with Weightron and their systems allow us to keep accurate electronic records for both incoming tyres and outgoing finished product".