SQ5ZA3 Knuckle Crane Lifting Stone Slabs in India

Stone slabs standing on edge in a truck body, a crane hook above them and workers guiding the load by hand: two photos and a 20-second video from our customer in India show a red BOB-LIFT SQ5ZA3 knuckle boom crane at work in a stone yard.

At a glance: SQ5ZA3 5 t knuckle boom crane · India · loading stone slabs in a stone yard · 2 customer photos and 1 video.

What the photos and video show

• The truck. The red crane, marked BOB-LIFT and SQ5Z, sits behind the orange cab of a truck with a white dropside body. A blue operator's seat is raised on top of the crane column, so the operator works from above the deck.
• Folded for the road. The rear photo shows the booms folded back over the column, with the oil cooler fans fitted beside it.
• Stone slabs. In the video the outriggers are down in a stone yard. The crane lifts a large slab on a sling while workers steady it by hand, and more slabs stand on edge in the truck body.

These are the customer's own photos and video. No slab weights, dates or comments came with them.

SQ5ZA3 specifications

The SQ5ZA3 is a 5 t knuckle boom truck-mounted crane with a maximum lifting moment of 10.5 t·m and three boom sections. All figures below are read from the technical department's dimension and load chart drawings.

Lifting moment is the load times its distance from the slewing centre. That is why the rated load drops as the boom reaches out. For example, the SQ5ZA3 lifts 5,000 kg at 2.1 m but only 1,100 kg at 8.05 m. Outrigger span is the width between the outrigger feet when they are fully out. Set them on firm, level ground, such as concrete or compacted gravel, before each lift. For ground and outrigger rules, see the OSHA cranes and derricks standard.

At 4.45 m from the slewing centre the crane is rated for 2,350 kg; at the full 8.05 m reach it is 1,100 kg.

The SQ5ZA3 product page has the dimension drawing and the full specification. The same model is in our delivery records from Fiji, on a test stand before mounting, and Indonesia, lifting a wheel.

Lifting stone slabs with a knuckle boom crane

Stone is heavy for its size, and slabs are wide and thin, so they swing easily once they leave the ground. Three checks matter before each lift:

1. Work out the slab weight. Granite weighs about 2.7 t per cubic metre. A slab 3 m long, 2 m high and 30 mm thick is about 0.5 t, but a block of the same size 200 mm thick is about 3.2 t. That is more than the 2,350 kg rated at 4.45 m, so it can only be lifted close to the column.
2. Use lifting gear made for stone. Slings, slab clamps or lifting frames must be rated for the slab and hold it so it cannot slide out. Protect slings where they bend around sharp stone edges.
3. Keep hands off where you can. In the video workers guide the slab by hand. A tag line lets them steady it from further away, and nobody should stand between a moving slab and the stack or the truck body.

The raised seat gives the operator a view over the dropside body to where each slab lands. How we fit cranes to customer chassis is on the mounting and shipping page, and other capacities are in the knuckle boom truck mounted crane range.

Checking a truck for the SQ5ZA3

Before you order, check three things on your truck. They decide whether the SQ5ZA3 fits it.

• Payload. The crane weighs 2,286 kg. Take this off the truck's payload, then plan the body and the loads you carry with what is left.
• Hydraulic power. The crane needs 35 L/min at 28 MPa, about 22 kW. The power take-off and pump on your truck must give at least this.
• Outrigger room. The outriggers span 2,272 to 5,122 mm. Make sure the frame has room for them, and that your job sites do too.

Send us the make, model and wheelbase of your truck through the contact page, and our team will check the fit.

Record compiled by Achord Chan, Product Operations Director at BOB-LIFT, from the customer's photos and video and the technical department's drawings.