A lifting tong is a device that applies pressure or support with a scissor mechanism to lift a part or product. While they are used efficiently and safely in many industries, the material handling advantages they offer are too often overlooked.
The truth is that less efficient solutions continue to be used. Wrapping a chain or sling around an item or product doesn’t provide for a safe or secure lift. Similarly, using a component that is not rated for lifting, such as a standard C-clamp, might appear safe, but if the tool has not been designed and manufactured for lifting, it is an accident waiting to happen.
Lifting tongs do lend themselves to handling a round product, but they can be designed to lift a variety of other shapes and sizes of material. There are even special tongs designed to lift rocks and boulders. While the principles remain the same, a tong will commonly be customised to the specific needs of a material handling application or load.
Operatives at steel mills can use billet tongs to load material onto a rolling line. Steel fabricators might use a different type to load and unload steel trucks. The construction industry uses lifting tongs to pick up the concrete barrier sections that are commonplace along the highway. Barrier grabs are often spotted working with concrete barriers on infrastructure projects.
Product shape, size and material type will drive the design of a custom lifting tong, but there are multiple other factors that need to be defined, such as whether the product is being picked out of a box or crate; the amount of room available around the part; what the user needs to do with the product after they pick it up; and the obstructions that might be present when they set it back down.
Types of tongs
Even within a single manufacturer’s line of lifting tongs, there is often more than one option that could meet the requirements of a material handling application. To begin the selection process, it should be decided whether a single or dual gripping tong is required.
A single tong will have one set of arms that, when lifted, provide a scissoring action to grip a product. A single type of tong only provides one point of contact on the load being picked up, which means the clamp must be centred over the length of the product to keep it level.
A dual gripping tong consists of two or more single tongs suspended along a main lifting beam. The tongs are positioned at a defined distance apart along the beam, which allows the lifting points to be spread out over the length of the load, which will help make it stable.
Bale lifting tongs are used to lift square or rectangular bales of paper, cotton and other materials. A wide gripping surface helps load stability, while an auto-latch mechanism facilitates one-person operation. Dual custom gripping tongs are better suited to handling steel dies, boxes or crates. Contoured pads distribute the force applied to the load over a larger surface area. There are other tongs for lifting round pipe sections, concrete products and structural steel beams. A friction tong applies an inward or outward force with a scissor or lever mechanism to grip a product allowing it to be lifted. An indentation tong will typically have some sort of teeth or points to provide additional support.
Lifting tongs are designed to be used with any type of overhead crane or chain hoist. A mobile crane would be most common in the construction industry, while an electric overhead travelling crane might be used above the hook in industrial settings.
As with any below-the-hook lifting device, regular inspections are a requirement. Key points would be any damaged, loose, worn or missing components. Maintaining a lifting tong will consist of proper lubrication and general tightening of fasteners. A lifting tong must be used as intended, meaning users must not overload the device, and should always make sure the load is level and stable. Manufacturers provide user manuals to define proper use and care.
Getting a grip
Caldwell recently supplied four lifting tongs for a major aluminium plant expansion in the US’s Midwest. The products included a 60,000lbs capacity, two-point swivel tong for ingots 74” to 84” wide; and 50,000lbs capacity, four-point horizontal tong for 54” to 67” wide aluminium ingots.
