Vertical and horizontal plate lifting clamps: pairs, jaw range and when to use each

Steel plate has no lifting points, so the lifting point has to be brought to it — a clamp that bites the edge and holds by friction and the grip of hardened teeth. Which clamp depends on which way up the plate travels: edge-up from a rack, flat from a stack, or turned over on the way. Get that wrong and the clamp is loaded in a direction it was never designed to hold.

/01Clamp types on our listings.

/02Vertical clamps.

A vertical clamp has a fixed jaw and a toothed cam. Once the plate edge is in the mouth, the cam is set against it — on the CDH, a hardened cam in a die-forged alloy body — and the pull of the load rotates the cam harder into the plate, so the grip rises with the load. That is what lets a vertical clamp lift a plate from a rack or turn it from flat to vertical. The locking mechanism holds the cam closed before the lift starts, so the clamp cannot shake loose while the plate is still light. Our CDH jaw openings run from 0–20 mm at 1 t to 0–60 mm at 8 t.

/03Horizontal clamps work in pairs.

Horizontal clamps grip opposite edges of a plate or a bundle and lift it flat, hung from a spreader beam or a two- or four-leg sling. A single horizontal clamp cannot hold a plate on its own, which is why our PPD, PDQ and THK clamps are rated per pair — the WLL is what two clamps lift together, at the sling angle the maker allows. Long plates that sag between two clamps need two pairs on a beam. The PPD has a replaceable jaw plate; the THK and THKS are for thin sheet, from 0.5 t per pair.

/04Beam clamps and section clamps.

A beam clamp is not a load-gripping clamp at all: it fixes to the flange of an I-beam to make a temporary anchor for a chain block or hoist. Ours are listed from 1 t to 10 t; the 1 t to 5 t sizes fit flanges from 75 mm or 80 mm up to 220 mm, and the 10 t fits 90 mm to 320 mm. The beam must be able to carry the load at that point. The LC clamp is a horizontal clamp for steel sections, listed from 1 t (1–13 mm jaw) to 3 t (12–35 mm jaw). Hoists to hang from a beam clamp are compared in chain block, lever hoist and electric hoist.

/05Ordering a clamp.

Give the plate thickness range, the heaviest plate or bundle, whether it travels flat, edge-up or is turned, and how it will be slung. For horizontal clamps, say whether you need a pair or two pairs; for beam clamps, give the flange width and thickness. Our clamps ship with the manufacturer's test certificate. Clamps, like all lifting accessories, are examined periodically — see lifting equipment inspection in the UAE.

For the rest of a steel erection crew’s kit, see steel erection rigging equipment.