Cold chain specialist turns to tailored truck power solution

Dave Mayne, Gloucester site manager for Partner Logistics says: "The new fleet has already made a considerable improvement to our operations. We have more focus on the total solution rather than simply treating the batteries as something that comes with the truck.”

With 72,000 pallet capacity and annual throughput exceeding 600,000 pallets, the site operates 24/7 with just 29 people. The main 30m, 18-pallet high main chamber is fully automated with cranes and conveyors. Flexibility is supported by three pallet stackers working in a smaller chamber with conventional racking while five electric counterbalance trucks load delivery vehicles.

During 2014 the original fleet was reaching end of contract. Partner Logistics had experienced a number of truck and battery-related performance and reliability issues, particularly in the two preceding years, that led to unexpected outages and damage to equipment. Recognising it needed a different approach the company visited various sites to see potential replacement trucks from the leading manufacturers and discuss experiences with other users.

"The solution proposed by Crown and EnerSys was not the cheapest but we are confident it will deliver what we need over the whole contract,” says Dave Mayne. 

From the outset Crown took the approach that the batteries would be integral to the solution. The company’s account manager Nathan Sheridan approached counterpart Kris Boulton at EnerSys to discuss how they could devise a joint solution to meet the demands of a -26oC cold store. 

Specifying the right battery is particularly important in a cold store where the arduous conditions and low temperatures inevitably reduce performance compared with ambient applications. After assessing the projected demands EnerSys proposed batteries from its Hawker Waterless range, as well as Hawker LifeTech high frequency chargers.

"We were guided by EnerSys on the choice of batteries and chargers,” says Max Longley, Gloucester site operations manager for Partner Logistics. "Maintenance processes are much simpler and there is reduced risk of over- and under-topping which helps maintain battery performance and reliability. Frozen batteries had been an issue and reducing the amount of water helps in this environment.”

A key objective for Partner Logistics was better battery management. Drivers are under strict instruction to change a battery only when it reaches 20 per cent state of charge and replace it only with a fully charged unit. Information from the truck’s battery is available through Crown’s fleet management system InfoLink to confirm the status of the units on board each truck and in each charging station. Simple LED indicators on the chargers show operators which batteries are fully charged and available for use.

InfoLink detects when a battery is changed and records its state of charge at the time. Since the installation went live the number of batteries swapped with the wrong state of charge has fallen to almost nil. On the few occasions when this has happened the system has issued an alert and managers have been able to respond immediately.

"InfoLink shows us how the trucks and batteries are being used and with the alerts we often know something has happened before the operator has a chance to tell us,” says Max Longley. "We can be proactive with our team and use the information to identify when additional training is needed.”

The previous installation utilised one spare battery for each lift truck. Following its initial assessment EnerSys identified that the total number of each type could be reduced by one. This lowered the overall cost for Partner Logistics and ensured redesigned charge and change areas would occupy less space.

The charging area for the counterbalance trucks was previously accommodated in a large room adjacent to the loading bay. Its footprint was big because the chargers stood on the floor. Now the much smaller Hawker LifeTech chargers are mounted above the batteries on new charging stations devised and installed by EnerSys. Battery connectors are fixed above and behind the roller beds to keep them off the floor and prevent damage. Cables have been shortened to dissuade operators from parking and charging. The reduced size of the new installation allowed its relocation to a smaller room. The original room has been converted by Partner Logistics for value-added tasks including a growing rework service. 

EnerSys devised a similar configuration for the pallet stacker charging room. In both areas batteries are changed using a battery transfer system (BTS) developed by Crown based on their hand pallet trucks. The BTS used to swap the counterbalance batteries locks onto the truck to prevent unexpected movements and promote safety during changing.

"We expected the operation to be better and more reliable but the real impact will come after three years,” concludes Dave Mayne. "The relationship works well. Our contract is with Crown but we know we can go direct to Kris if there is an issue with the batteries and he will work with everyone to sort it out. If you work together you get a result.”