Handling Loads Without Pallets: Bale Clamps and Drum Clamps

Not every load arrives on a pallet. Bales come strapped, drums come on their own rims, and both need a bale clamp or drum clamp that grips the product itself. This article covers what each attachment handles, how to size the clamping force, and when a standard fork truck will not do the job at all.

1. When the load refuses to sit on a pallet

A pallet is a delivery decision. Some cargo never gets one.

Waste paper, cotton, wool and synthetic fibre are pressed into bales at the baler and strapped there. Adding a pallet costs money, adds 15–25 kg of dead weight, and gives the bale a chance to shift on the forks. Soft-wrapped goods — shrink-wrapped white goods, bagged resin, textile rolls — are often too unstable on forks to lift safely. Steel and plastic drums are lifted by their own body, not by a base, because there is no base to slide under.

Three conditions point to a clamping attachment:

• The product is dense enough to resist squeeze pressure without crushing.
• The outer layer is either the product itself (bales) or a container designed to take side load (drums).
• The load has a consistent, repeatable shape. Clamps reward repeatability; odd shapes punish it.

If the load is loose, fragile, or varies in size from delivery to delivery, forks and a slip sheet or a custom jig usually beat a clamp.

2. Bale clamps and drum clamps: what each one grips

Bale clamps

A bale clamp uses two vertical plates that close horizontally on the sides of a bale. The load is held by friction, so clamping force has to stay inside a narrow band: enough to hold the bale during travel and braking, not enough to burst the straps or crush the fibre.

Typical materials and their working densities:

Force is set two ways. Mechanical clamps use the hydraulic circuit pressure and a fixed plate geometry, so the operator only opens and closes. Hydraulic clamps with a pressure regulator let you dial the squeeze down for wool or up for PET. On a 1.5-tonne class truck, a bale clamp typically runs 8–14 bar at the clamp cylinder and produces 4–8 kN of clamping force per plate; the exact figure comes from plate area, not from the truck's lifting capacity.

Two operating habits matter more than the spec sheet. First, always lift with the bale centred between the plates — an off-centre bale triples the pressure on one edge. Second, never travel with the mast tilted forward; that swings the bale away from the plate and lets it slide.

Drum clamps

Drum clamps grip the drum around its circumference, either the body or the top rim.

Single-drum clamps hold one drum. They are light, cheap, and easy to see around. Most use a spring-loaded or hydraulically actuated jaw that closes on the drum body.

Double-drum clamps hold two drums side by side on the same carriage. Throughput roughly doubles per trip, but the attachment weighs more and the load centre moves forward, so the truck's rated capacity drops.

Steel drum vs plastic drum. A steel 200-litre drum resists side load well and can be gripped on the body. A plastic drum deforms under the same force — hit it with a clamp set for steel and it will oval, crack at the chime, or pop the lid. Plastic drum clamps use wider contact pads and lower pressure, often with a grip on the top rim instead of the body. Never assume a clamp rated for steel will handle HDPE safely.

Standard 200-litre drum dimensions (the baseline most clamps are built around):

Those numbers drive the truck choice. A 220 kg gross load at a 500 mm load centre is well inside a 1.5-tonne truck's chart — until you add the clamp. A double-drum clamp hanging 600 mm forward of the carriage can cut usable capacity by 30–40%. Read the capacity chart with the attachment fitted, not the bare truck's chart.

3. Comparison: bale clamp vs drum clamp vs standard forks

The trade shows up in two places: capacity and damage. A clamp costs you lifting capacity and adds a damage mode that forks do not have. What you buy back is the pallet — its cost, its 15–25 kg, its storage space, and the return journey.

4. How to choose

• Measure the load first. Bale width and height range in millimetres, drum diameter to the nearest 5 mm. A clamp sized for a 1,200 mm bale will not close on a 900 mm one without a stroke change.
• Match capacity with the attachment fitted. On a 1.5 t truck, a 500 kg bale clamp at 550 mm load centre typically leaves 900–1,050 kg of usable capacity. If your bale weighs 600 kg, step up to a 2.0 t or 2.5 t truck.
• Set clamping force to the material. 4–6 kN suits wool and tobacco; 8–12 kN suits dense PET or wet OCC. Ask for a pressure regulator if you run more than one material.
• Choose single or double by trip count. Under 40 drum movements per shift, single is usually enough. Above 80, a double-drum clamp pays back the capacity loss within a year.
• Steel or plastic decides the pad. Wide, smooth pads with lower pressure for HDPE; narrower, harder pads for steel. Do not share one clamp between the two without changing settings.
• Check the hazardous area classification. If the drum carries a flammable liquid and the filling or decanting point is a classified zone, the truck itself needs Ex protection — the clamp alone is not enough. A Zone 1 or Zone 2 requirement means an explosion-proof truck with Ex-rated motors, controllers and wiring, plus a spark-free fork or clamp assembly.
• Confirm the mast and carriage. Clamps are heavier and sit further forward. A 3-stage full-free-lift mast may be needed if you work inside containers or under racking beams at 4,000 mm.
• Plan the aisle. A double-drum clamp adds 600–900 mm to the effective load length. In a 3,000 mm aisle that can decide between a reach truck and a counterbalance.

Do hazardous drums need an Ex-rated truck?

Sometimes, and the drum is not the deciding factor — the atmosphere is.

A sealed 200-litre drum of solvent is not itself a hazard to the truck's electrics. What matters is whether the truck is operating where a flammable vapour cloud can form. Filling points, decanting stations, drum-opening areas and sumps are where vapour escapes, and those are the spots normally classified as Zone 1 or Zone 2.

If the truck never enters a classified zone — it only moves sealed drums across an open yard or a general warehouse — a standard electric truck with a drum clamp is normally acceptable. If it enters a classified zone, the truck must be explosion-proof rated: Ex motors, Ex controllers, Ex wiring, and a clamp assembly with no exposed sparking parts. In practice that means an explosion-proof truck carrying a drum clamp, not a standard truck with an Ex sticker.

Two more points. First, plastic drums generate static when handled dry; a steel drum clamp with a proper earth path is the safer pairing in solvent service. Second, damaged drums leak. A clamp will not tell you the drum is compromised — inspect before lifting, and never lift a drum with a visible dent at the chime.

5. FAQ

Can a bale clamp handle both waste paper and plastic film bales?

Usually not with the same settings. Wet OCC bales at 500 kg/m³ need 9–12 kN to hold through braking; plastic film bales are slippery and compressible, so they need similar force but much wider contact area. Run one clamp with a pressure regulator and change both pressure and plate type, or keep two attachments on quick-change carriages.

What is the maximum drum weight a single-drum clamp can lift?

It is set by the truck, not the clamp. Most single-drum clamps are built for 250–350 kg per drum, which covers a full 200-litre steel drum at roughly 220 kg. Beyond 350 kg you are into 2-drum or heavy-duty clamp territory and the truck capacity chart has to be recalculated with the attachment weight.

Will a drum clamp damage a plastic drum?

It will if it is set for steel. HDPE drums oval under the 8–12 kN used on steel, and the damage often appears later as a cracked chime. Use a plastic-drum clamp with wide pads at 3–5 kN, and grip the top rim where the drum is stiffest.

Do I need a different attachment for a closed-head and an open-head drum?

Not always. A body-gripping clamp works on both. A rim-gripping clamp, common for plastic drums, needs the drum to have a suitable chime or top ring — open-head drums with a light locking ring may not have one. Check the ring, not just the drum.

How much capacity do I lose when fitting a clamp to a 2-tonne truck?

Expect 30–40% with a double-drum clamp at 650 mm load centre, and 20–30% with a bale clamp at 550 mm. On a 2.0 t truck that leaves roughly 1,200–1,400 kg usable. Always use the capacity chart issued for the truck with that specific attachment.

Can a clamp truck also move pallets?

Yes, if you use a quick-change carriage or a fork-and-clamp combination. The compromise is weight and load centre. Many operations keep one clamp truck and one standard truck rather than paying the capacity penalty on every pallet movement.

6. Related products

• Forklift Attachments
• Customized Series
• Special Applications (Ex / cold store)
• Customized & Accessories
• Forklifts