Smarter handling
August 1st 2004

UK manager of Demag Cranes and Components, Tarik Alkhalil reports on the development of state-of-the-art intelligent lifting equipment for niche applications Over a period of years manufacturers and suppliers of materials handling systems have seen order books dominated by the volume sales of commodity products. By commodity products I mean standard and semi-standard cranes and hoists, installed to lift, move and lower an object from point A to point B. Granted, technological advances and the incorporation of features such as frequency inverters for speed control and positioning accuracy have significantly improved the performance of such equipment, but they remain essentially commodity products. And for a wide range of industrial and manufacturing environments, commodity products will continue to fit the bill. However, as certain manufacturing and logistics operations become increasingly specialised, we have experienced growing demand for bespoke materials handling solutions developed for specific applications. Such demands are challenging suppliers and manufacturers to develop new process systems that deliver optimum performance, higher reliability, value added benefits and, most importantly, increased levels of safety. Rapid advances in technology have allowed crane manufacturers to push back the boundaries in the development of innovative materials handling systems. Two case studies, detailing crane installations in contrasting materials handling environments, demonstrate how lifting solutions can be tailored to meet the specific application. Baxter Moving Excellence Baxter Moving Excellence, a leader in the international removals and storage sector, has recently opened a new facility in Carlisle. Over half of the new 3100m2 warehouse is dedicated to storage within 20ft and 25ft ISO steel containers. The containers can be stacked up to six high to accommodate 460 units. To facilitate the movement of the ISO containers, Baxter specified a fully automated Demag ContainerMaster crane system, modified and developed specifically for the application. Our solution comprises a 14t SWL overhead crane, with a four wheel crab, equipped with two Demag wire rope hoists, each rated at 8t SWL. The system features inverter controls, providing infinitely variable speeds for motion in all directions. The crane is inherently safe, with fail safe locking systems and feedback to the crane, to prevent lifting if the container is not properly located within the container grab. A particular feature of this handling system is its ability to move containers from the marshalling area to a predetermined storage location and memorise the position for retrieval. Should a container be relocated, the systems computer is automatically updated. When the container is dispatched, the operator keys in the container number and the intelligent crane automatically travels to the appropriate location for retrieval. To protect against costly downtime the crane is equipped with GPRS modem technology which relays data to our remote monitoring station. Data received can be used to monitor system performance and highlight issues for routine maintenance. In the event of system failure, symptoms can be assessed and engineers informed of the fault before they arrive at site, saving time and resources. Castle Cement Castle Cement is the UKs second largest producer of cement and the companys Ketton plant, in Rutland, outputs more than 1.3 million tonnes each year. The production process involves ground limestone and clay being passed through a kiln to form clinker. The clinker is then ground in mills along with small amounts of gypsum and limestone to make cement. As part of modernisation of the Ketton plant we designed, manufactured and installed a 12t SWL x 24.38m span, fully automatic grabbing crane with an electro hydraulic clamshell grab unit. The fully automated, intelligent crane system is controlled and monitored remotely. The crane ensures clinker arriving from the kiln is distributed in the store and the hoppers feeding the cement mills are replenished. Sensors on the hoppers inform the control system if stocks are low and the crane travels to the area where the appropriate material is stored, picking up the load and depositing it in the relevant hopper. The crane also feeds coal into the coal mill, supplying the kiln with pulverised fuel. The cement production environment is particularly arduous with ambient temperatures of up to 40C and considerable amounts of dust. Our crane solution was designed to meet these conditions and handle the heavy duty application of cement production, which is a 24/7 process. To meet the vast quantities of material that need to be moved, the crane has a hoisting speed of 100m per minute and a travel speed of 120m per minute. In addition to increased productivity, the crane system has also created environmental benefits. When unloading material, the crane remembers the height and the location of the last load dumped and gently deposits the next full grab on the heap, minimising the amount of dust created. The installations at Baxter and Castle Cement are just two examples of how lifting equipment can be tailored for niche applications. As we continue to embrace the latest technology, we will see the evolution of materials handling systems that work harder and smarter to provide value added benefits for the user.

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