3D Model — Orbit & Inspect
Anatomy of an Edge Lift Clamp
Cam Jaw
The gripping mechanism that bites into the panel edge. Serrated teeth provide friction grip. Cam action means the jaw tightens automatically as load increases.
Body
Heavy-duty forged steel housing that contains the cam mechanism and transfers load forces. Must be free of cracks and deformation.
Bail / Shackle Point
The top attachment point where the sling or shackle connects. Transfers the load weight to the crane hook via the rigging arrangement.
Adjustment Mechanism
Allows the clamp to be set for different panel thicknesses within its rated range. Must be correctly matched to the panel before lifting.
Spring-Loaded Safety Lock
Prevents the cam from opening under load or during transport. Must engage automatically and be checked before every lift.
Purpose
Edge lift clamps are designed to lift concrete panels and slabs from a horizontal position to vertical — this is known as tilt-up construction.
The clamp grips the edge of the panel, allowing the crane to rotate it from flat on the ground to standing upright for installation.
How It Works
The cam jaw tightens as the load increases — the heavier the load, the tighter the grip.
This is a self-locking mechanism. The clamp cannot release while under load.
Capacity & Selection
| Size Range | Typical WLL | Panel Thickness |
|---|---|---|
| Small | 1 – 3 t | 75 – 150 mm |
| Medium | 3 – 7.5 t | 125 – 250 mm |
| Large | 7.5 – 15+ t | 200 – 400 mm |
Critical Selection Rules
- Always match clamp capacity to BOTH load weight AND panel thickness
- A clamp rated for the correct weight but wrong thickness will not grip properly
- Never exceed the rated capacity — check the stamped WLL on the clamp body
Critical Operating Rules
- Must be matched to panel thickness — clamp range must cover the actual panel dimension
- Only use on materials specified by manufacturer — concrete, not timber or steel
- Never shock load — sudden jerks can exceed cam grip capacity
- Must be installed by a qualified rigger or dogger — not general labourers
- Ensure the panel edge is clean and undamaged — loose aggregate reduces grip
- Use exclusion zones during tilt-up — panels can swing or fall if rigging fails
- Always use a tag line to control panel rotation during tilt
- Check that the safety lock engages before signalling the crane operator to lift
Inspection & Rejection Criteria
Inspect edge lift clamps before every use. Remove from service if ANY of the following are found:
Reject Immediately If
- Worn cam teeth: reduced serrations mean reduced grip — catastrophic drop risk
- Damaged spring mechanism: safety lock may not engage — clamp can open under load
- Bent bail: deformed attachment point creates uneven loading
- Cracked body: structural failure imminent under load
- Missing markings: no WLL stamp or serial number = no use
- Stiff or seized adjustment: cannot be set to correct panel thickness
- Corrosion or pitting: reduces structural integrity of body and cam
Good Condition Indicators
- Cam teeth sharp and evenly worn
- Spring lock snaps into position firmly
- Bail rotates freely, no cracks or deformation
- Adjustment mechanism moves smoothly through full range
- WLL marking and serial number clearly legible
- Body free of cracks, dents, and significant corrosion
Tilt-Up Lifting Process
- Step 1: Verify panel weight and thickness — select correct clamp size
- Step 2: Adjust clamp to panel thickness — ensure full cam engagement range
- Step 3: Attach clamp to panel edge — confirm safety lock engages
- Step 4: Connect rigging to bail — use correct shackle and sling arrangement
- Step 5: Take up slack slowly — confirm clamp seats firmly before load transfer
- Step 6: Lift and rotate — use tag lines to control swing
- Step 7: Position panel — brace before releasing clamp
- Step 8: Only release clamp once panel is fully braced and stable
Applicable Standards
- AS 3850 — Tilt-up concrete construction — covers design, manufacture, and use of lifting clutches and edge lift clamps for tilt-up panels
- AS 4991 — Lifting equipment — general requirements for design, manufacture, and testing of lifting devices
- NSW WHS Regulation 2017 — duties for doggers and riggers when using lifting clamps
Remember
Edge lift clamps are classified as lifting equipment under WHS Regulations.
They must be designed, tested, and maintained in accordance with the manufacturer’s specifications and relevant Australian Standards.