Lift Truck Tips: Don’t get left out in the cold

Of all the costs associated with operating a cold storage facility, lift trucks are among the slipperiest to pin down. A cold warehouse’s capacity, throughput and cooling expenses can be quantified, but that environment’s impact on lift trucks, batteries and productivity are more nebulous. To help identify some of the opportunities and dodge the pitfalls of cold storage applications, Modern spoke with Crown Equipment’s Jim Gaskell, director of global technology and business development.

First, Gaskell says, it’s important to buy a forklift made at the factory for cold conditions. Special considerations should be made at the point of assembly for components including control cabling, switches, hoses, greases and even paint. “Never let someone convince you they can retrofit a truck for the cold,” Gaskell says, “it doesn’t work out well.”

The right tires are important for the icy or slippery conditions, and the oil blend should reflect the application, whether a 50/50 freezer oil blend or 100% freezer oil in a blast freezer, for example. Nearby equipment like strip curtains between temperature zones should also be inspected for potential catch points that can damage equipment, the curtains and energy efficiency.

The physics of lead-acid batteries create dramatically different performance in cold and ambient environments, and it’s critical maintenance and charging practices are adjusted accordingly. When a battery drops to 0 degrees—even if fully charged—it has already lost 20% of its available capacity, Gaskell says. Some customers equip cold storage lift trucks with the biggest battery possible, but when it comes time to charge, Gaskell says low temperatures will cause battery chargers to detect an artificially low reading of volts per cell. This can confuse the charger into beginning the charge at a later point in the charge profile. Some chargers have settings for cold profiles, but battery-mounted modules are capable of communicating temperature to the charger so it can account for the inflated voltage readings.

The penalties for over-discharging are more severe in cold environments as well. As it discharges, the specific gravity of a battery cell gets closer to water. If not charged in time, it could freeze and permanently damage the battery. Lithium-ion batteries are susceptible to many of the same temperature-related impacts as lead-acid, and in some cases the effects are even more pronounced.

Gaskell cautions customers to select equipment with enough compartment space for an operator to bundle up and still be comfortable and safe. Similar considerations should be made for interaction with controls and touchscreens while wearing heavy gloves. He notes an increased trend toward narrow aisle cold storage for pallet-in, pallet-out applications. Narrow aisles lend themselves to turret trucks that can have heated operator compartments.

“If the goal is to keep the operator in the freezer,” Gaskell says, “then with a heated cab they can wear a T-shirt and stay in there as long as the truck holds a charge.”

Whether bundled or heated, an operator alone in a freezer is rarely subject to much oversight, Gaskell says. “There are not a lot of people running around in there with clipboards, so there tends to be a lot of abuse,” he says. “Maintenance becomes more important in the freezer than in dry warehouses, where there is a big difference in the level of supervision.”