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November 1st 2010 Page 13Tel: 01923 272960FORKTRUCK NEWSEmail: warehouse@flame1.comHawker XFC batteries from EnerSysare being used in a new project withautomated guided vehicles (AGVs)manufactured by JBT Corporation forhandling print reels and other loads at acommercial printing plant in Sheffield,UK. The Hawker XFC units werechosen by JBT Corporation because ofthe batteries’ compact size/shape, heavyduty performance, and quick/ondemandcharging, without the need formaintenance. These features enabledthe batteries to be integrated into theJBT Corporation AGVs and deliver efficient,round-the-clock operation.AGVs are battery powered, computercontrolled vehicles which operateunmanned to complete routine materialmovements in production plants andwarehouses. There is a certain level ofcustomization in AGVs because they aretypically designed for the requirementsof the specific material handling application(e.g. load weight, load dimensions,aisle width, pick up points, drop off points,hours of operation, etc.). In analyzing thespecific application, AGV engineers designthe AGV to safely support and move eachload type while maximizing the amountof time each AGV is available to dowork. To maximize AGV availability, theoptimum mix of battery capacity, batterysize, battery weight and battery chargefrequency/time is required. This allowsthe operational needs of the application tobe met by the minimum number of AGVs.The equipment required by the printingplant in Sheffield is a good example ofwhat is required in this design process. Thecustomer produces magazines and otheritems for newspaper colour supplementswhich are wound spirally onto large, twometre diameter reels as they are printed.They wanted an automated method ofmoving these reels between the printing,assembly and packing areas. Each reeltypically holds thousands of magazinesand weighs up to 1400kg. The plant operatesaround the clock and the customerneeded equipment that could operatealmost continuously to ensure it couldmeet the demanding service commitments.After assessing the flow of materialsthat were required to support efficientplant operation, JBT Corporationdesigned an AGV that would safely pickup and deliver the required loads. Theexisting infrastructure at the plant dictatedsome of the design parameterssuch as the maximum length and width ofthe AGVs. Factors such as weight and sizeof the loads and the need to install andaccess safety sensors and guidance equipmentwere also critical considerations. Thebatteries provide some of the weight thatcounterbalances the load but the vehicledesign had only a limited amount of spaceon the vehicle available for the battery.The shape and size of the compactHawker XFC battery unit offered severaladvantages compared to other battery technologies.Each XFC battery is approximately30 per cent smaller than comparable conventionalunits with the added advantage thatit can be placed in any orientation, includingupright, on its side or on its end because thedry gel electrolyte will not leak. These featuresallowed use of a compact and efficientbattery pack made up of 12 smaller batteryunits in various orientations on three layersto make the most efficient use of the availablebattery compartment space and achievethe required 48V, 530A capacity needed.Another critical consideration in thechoice of the Hawker XFC battery wasits performance in use. The AGVs aredesigned for almost continuous operationsand battery changing or swapping- which is sometimes used on AGVs -was not preferred by the customer. TheXFC battery delivers maximum performancebecause it stores around 30 per centmore charge than conventional units whichextends the amount of time the AGV canoperate before recharging. The XFC batterycan be charged from around 60 per cent dischargeto full capacity in under three hourswhen used with a Hawker Lifetech highfrequency charger. This combination of batteryand charger also supports intermittentor opportunity charging with shorter butmore frequent charge periods - and this doesnot adversely affect battery performanceor lifetime. It was this opportunity chargingmethod that was utilized in this applicationso that the AGVs are charged for a fewminutes whenever they are not being used.The AGVs are automatically commandedto navigate to one of the automatic chargingpoints distributed throughout the site. In thisway the batteries and chargers can supportnearly continuous AGV operation 24 x 7.ENERSYS DELIVERS ON-DEMAND AGV CHARGINGAnother attractive feature of the XFCbattery is its maintenance-free and nogassingperformance. Since one of theprimary goals of installing an AGVsystem is to increase personnel productivity,maintenance-free batteries areoften preferred by customers. And typicallywhen a standard battery is charged,it gives off gasses that must be ventedfrom confined areas. No gassing meansthe AGV can be used in confined areaswithout the need for special ventingequipment at the charging stations.Ten AGVs were integrated by JBTCorporation into this printing customer’soperations. An on-board laser-basedguidance system keeps the AGVs on thepredetermined paths. The position of eachAGV is also communicated to an on-sitemanagement control system so that operationof the fleet of AGVs can be continuallyoptimized. Obstacle detection on theAGVs is supplied by additional laser basedsensors which bring the AGV to a safe stopbefore it contacts any obstacle that mightbe in the AGV’s path. JBT Corporation’slaser guided AGV systems are very flexibleand scalable and as the movement ofmaterials in the printing plant grows andchanges in the future, the AGV systemcan quickly be reconfigured and expandedto support the new requirements.EnerSys Motive PowerKaren SmithTel: 0161 727 3800email: karen.smith@uk.enersys.comwww.enersys-hawker.comwww.enersys.comSTAND: 20F30