A cube design will also allow you to store more goods because you don’t need wide aisles for fork trucks. A cube design utilizes space more efficiently, with storage racks that reach up to the ceiling. “In a freezer environment, anytime you are refrigerating empty space, you are wasting energy and money,” Leber says.
Leber cites a recent ASRS installation Swisslog provided to a frozen foods factory. “They were planning to construct a building with a manual operation using forklifts. They planned to put in 10,000 pallet positions. We showed them how, by not changing anything in their plans, they could get in 14,000 pallet positions. That is a 40-percent increase in storage over their original plan, which means that their per-pallet energy costs will be reduced by about one-third.”
The beauty of an automated warehouse is that all of its material flows are choreographed. “You are immediately inducting products into the system from receiving and the system automatically conveys them into the warehouse and puts them away in a logical and methodical way,” explains Leber. “When you are assembling your orders, there is never a situation of people hunting around to find products because they are always where they need to be. Products are picked in an efficient and logical sequence, leaving the cold facility only when required. Whereas frozen goods in a manual system could spend 20 minutes or so in a non-freezer environment and then you are always questioning the shelf-life integrity of those products.”
Of course, the drawback of manual deep-freeze warehouses is the harsh environment itself, which breeds numerous opportunities for inefficiencies. “Trucks tend to have higher breakdown rates and accident rates,” Leber says. “Product damage rates are higher and accuracy rates are lower because workers just want to get in and out of the environment as quickly as possible. In a manual picking situation, people are more apt to sacrifice quickness over accuracy which means you end up shipping the wrong frozen food product and this gets to sustainability. Many times, people forget that inaccuracy impacts sustainability because if you ship the wrong products, they only have to be returned and then reshipped. A lot of energy and cost goes into keeping those products frozen. So you wind up with additional electricity costs on both ends.”
Leber notes that Swisslog’s expertise in designing equipment to operate in these harsh environments is well documented in the industry. “We use special steels in designing and manufacturing our ASRS equipment. Our designs are built to be as maintenance-free as possible so you don’t have to have people going into these harsh environments to maintain the equipment.”
LTW Intralogistics Inc. in York, PA offers a solution using stacker cranes capable of changing aisles. “Most stacker crane manufacturers in the world typically offer cranes that run on floor-and ceiling-mounted rails that work back and forth all day long in that one rack aisle,” notes Daryl Hull, president of North American operations. Hull adds that LTW has been providing these cranes for decades in Europe, entering the U.S. market in 2000.
Once LTW’s cranes reach the end of a rack aisle, they can travel perpendicularly to that aisle and enter another aisle to continue storing and retrieving pallets. The advantage to this solution, explains Hull, is that you don’t need a dedicated crane to operate in a specific aisle—which can cause huge problems if that particular crane breaks down.
Say you have an ASRS solution in a facility with 10 aisles and 10 stacker cranes, each operating in its respective aisle, says Hull. If a stacker crane breaks down, there is no way to get products out of that aisle. “With LTW aisle-changing cranes operating in a situation like this, you just move the disabled crane to the maintenance area and the remaining cranes complete the tasks required in that aisle,” Hull explains. “And if the pallet you need in that aisle is for one of your best customers, our redundancy system can assure that pallet is retrieved. This is very important to maintaining a high level of customer service. Also, there are no additional costs involved in having to arrange a special trip to deliver that pallet. This goes to lowering your transportation and holding costs while lowering your emissions.”