Innovative on-site weighing and load management system for Tarmac.
The construction of a new cement plant at Tarmac's Tunstead Quarry in Derbyshire has helped to create one of the busiest sites in Europe, with product movements in excess of 6 million tonnes per annum.
With more than 650 vehicle and multiple train movements every day carrying cement, lime, chemical stone, concrete aggregate, and raw materials into and out of the site, Tarmac needed an integrated weighing, automated cement loading and traffic management system capable of interfacing with its own SAP system to meet the diverse needs of this huge multi-operation facility.
Following a comprehensive process of vendor assessment, Precia-Molen was chosen to design and build a system based around the market-leading GeneSYS and GSM software.
A flexible solution
Three Tarmac units are based at Tunstead Quarry. Aggregates, cement and lime (both bagged and bulk) are sold from the site, primarily under the name of Tarmac's subsidiary Buxton Lime and Cement, and delivered by road to locations throughout the UK. Chemical stone for delivery into the soda ash industry and to several of the companies' power stations where it is used for flue gas desulphurisation and cement are also dispatched by rail. In addition, up to 70 loads of raw material are delivered to the site every day.
The operation also encompasses the neighbouring Hindlow site and remote cement loading depots (rail fed) located in the West Midlands, Yorkshire and London.
Tarmac required a flexible and innovative on-site weighing and load management system that was capable of encompassing all operations. It needed to seamlessly integrate with the driver self-loading remote cement dispatch depots and handle more than 250,000 dispatches per year.
The system also needed to provide fast and accurate management reporting to monitor site performance and efficiency, as well as replace two existing dispatch systems.
Precia-Molen designed and built a bespoke solution utilising the power of GeneSYS. Utilising a weighbridge management system developed in-house by Precia-Molen, the system has aligned Buxton Lime and Cement business processes and systems with other Tarmac operations to increase flexibility and allow for future development.
The system integrates the operation of 8 weighbridges, two batch weighers for rail car loading, and a total of 18 driver consoles which enable fully automated dispatch operations across the site.
The installation also includes a new weighbridge entrance comprising three weighbridges, each incorporating a driver console, traffic barriers and traffic lights. A special fast track weighbridge facility enables even faster processing of Tarmac's regular fleet of vehicles, which can arrive 24 hours a day and pass simply through the entry and exit weighbridge station.
In operation
To accomplish seamless operation from ordering through to invoicing, the GeneSYS system is fully integrated with Tarmac's own sales order management system. When an order is placed, it is entered into the sales system and matched against quotes set up in SAP. GeneSYS then imports the order ready for collection or dispatch.
Preferred road vehicles visiting the site are pre-issued with RFID cards for identification. On arrival the vehicle drives onto the weighbridge and the driver presents the RFID card to the cab-height driver console and enters an order number. GeneSYS then weighs the vehicle and, if the tare weight is within expected tolerance, a loading slip is issued. Data for preferred vehicles is kept permanently by the system enabling faster verification and entry to the site.
If the vehicle is new to the site, the driver reports to the weighbridge operator, who inputs the registration details and order number. The vehicle is then weighed, issued with a loading slip and a single use RFID card and proceeds to the loading areas.
For bulk loading the driver proceeds to one of the numerous driver-operated loading points which feature automated loading. GeneSYS verifies the vehicle is at the correct location and signals via the integrated PLC that the loading operation can start.
For vehicles being directed to the aggregates stock pile area, the order details are sent to the loading shovel via a telemetric link where the operator verifies that the vehicle is to be loaded with the correct product and tonnage. Once loaded the vehicle proceeds to the check weighbridge where the order weight is checked against the loaded weight and if within tolerance is directed to the exit weighbridge.
For bagged cement or lime products, the driver simply presents his loading slip to an operator. Once loading is complete, confirmation is entered into GeneSYS and the driver proceeds to the exit weighbridge.
All vehicles return to the exit weighbridge to receive their dispatch documentation. The RFID card is inserted into the driver console, allowing the driver to confirm the final weight and receive the relevant documentation. Where multiple loads are required, the RFID card is returned to the driver for future use - otherwise it is retained.
In addition to the continual road traffic multiple rail dispatches of either cement or aggregates leave the site every day, delivering product either to major customers or to Tarmac's remote dispatch depots.
Cement rail loading is managed by two Precia-Molen batch weighers with the loading details entered into GeneSYS for integration into the site's other operations.
Raw materials and fuel are delivered to the site by road. As with the sales process, a vehicle may arrive either with or without a pre-issued RFID card. On arrival, GeneSYS compares the load details with the purchase order on SAP to confirm acceptance, and while the vehicle is being unloaded GeneSYS checks whether that vehicle has then been assigned to dispatch an order. If so, a loading instruction is issued which directs the driver to the appropriate loading point.
A Single System
Precia-Molen has provided a powerful and flexible system which has met or surpassed the needs of this busy and diverse quarry operation.
Tunstead now has a single system that encompasses the cement, lime, concrete aggregate and chemical stone operations, enabling fast and efficient throughput for high volumes of road and rail traffic.
The system provides integration and operation of rail-fed remote driver self loading dispatch depots, reducing road vehicle movements by up to 70 a day. Precia-Molen has also built in system resilience and data replication to allow remote dispatch depots to continue operation in the event of a communication failure.
In addition, the system is fully integrated with Tarmac's own SAP sales order and site systems, providing sophisticated management information.
The GeneSYS based solution has created a stable and expandable platform for the management of the entire site, doubling weighbridge operator capacity and providing important performance and management information.
The new system is one of the most advanced automated loading operations in Europe, and with the integration of the new remote dispatch depots in the West Midlands, Yorkshire and London, Tarmac has been able to expand into these market areas.
Nick Thomas, Buxton Lime and Cement Distribution Manager for Tarmac, said: "The installation of Genesys has brought about many benefits for Tarmac Buxton Lime & Cement. We have greatly improved our throughput of vehicles without increased staffing and enabled our remote cement depots to function as driver operated units. From the standard system originally purchased Precia-Molen and Tarmac have developed the program to meet the needs of the business and integrate all part of the various units. We are delighted with the functionality and flexibility of the current version."