UNIC URW-546-2 Mini Spider Crane with Hydraulic Jib

Model URW-546-2 | 4.0t × 2.5m Main Boom | 22.8m Lift Height with Jib | 1.4m Width | Four Hook Options as Standard | Tier 4 Yanmar Diesel

The UNIC URW-546-2 seamlessly combines operational flexibility with robust lifting power, featuring a new hydraulic jib with four hook options — surpassing the standard URW-546 with an expanded working height of up to 22.8m and an increased working radius of 17m. The URW-546-2 retains the slim 1.4m width for adept manoeuvrability through internal industrial doorways and confined spaces. Supplied as standard with an 850kg single-line hook, 850kg searcher hook, 850kg stub and 1500kg rhino hook, this is the most versatile machine in the URW-546 series.

Technical Specifications

Specifications above are taken from the UNIC manufacturer's spec sheet at standard configuration. Variants with electric, LPG or other options may differ slightly — full rated capacity charts supplied with each hire.

Key Features

• New hydraulic jib — extends working height to 22.8m and working radius to 17m
• Four hook attachments as standard — 850kg single-line, 850kg searcher, 850kg stub, 1500kg rhino
• 4 tonnes at 2.5m on the main boom — with the hydraulic jib adding reach without sacrificing capacity
• Tier 4 Yanmar diesel — clean-emissions compliance for indoor and low-emission zones
• Optional variable footprint — with slew and height limitation for working around obstacles
• 1.4m width — passes through standard industrial doorways

Suitable Applications

The URW-546-2 is the choice when the 546’s capacity is right but the lift height isn’t — the hydraulic jib unlocks 22.8m of reach for tall atria, multi-storey internal lifts, communications mast installation, and structural steel placement in high-bay buildings. The four-hook standard kit makes it ready for varied lifts on the same job without swapping attachments between visits.

How to Set Up and Operate the URW-546-2

1. Survey the working area, verify ground bearing capacity against the published point loadings and confirm overhead clearances are sufficient for the proposed boom geometry.
2. Track the crane into position using the operator's seat or radio remote. Ensure the chassis is on firm, level ground or that load-spreader mats are deployed.
3. Deploy the outriggers to the configuration required by the lift plan — set each outrigger angle and extension, ensuring stabiliser pads make full contact with the ground.
4. Level the crane using the bubble level / auto-level system and verify all outrigger interlocks are engaged before luffing the boom.
5. Configure the rope reeving (1-fall, 2-fall, 4-fall or 5/6-fall as applicable) to match the planned load and required rope length.
6. Set any working area, slew or height limits required by the lift plan via the safe load indicator interface.
7. Carry out a function test, confirm the moment limiter and voice warning system are operational, then lift to working position and complete the lift in accordance with the lift plan.
8. On completion, return the boom to the stow position, retract outriggers and secure the crane for transit or overnight parking.

Warning: Spider cranes must only be operated by CPCS / NPORS / equivalent-certified operators working to an approved lift plan. Never exceed the rated capacity at the relevant radius shown on the load chart. Power source: Tier 4 Diesel + Optional 400V Electric.

Safety Information

• The crane must only be operated by competent, trained and certified operators familiar with this specific UNIC model.
• A documented lift plan, prepared by an Appointed Person, is required for every lifting operation under LOLER 1998.
• Ground conditions must be assessed against the manufacturer's point loadings — supplied on request — before each lift.
• Outriggers must be deployed to a configuration that supports the planned load at the planned radius; mixed-extension configurations require a competent rating check.
• Never operate the crane outside the rated load chart, override the safe load indicator, or carry loads with the boom in an unintended configuration.
• Carry out daily pre-use checks of hooks, wire ropes, hydraulics, safety devices and the moment limiter prior to first lift each shift.

Inspection and Maintenance

Spider cranes must be subject to a Thorough Examination by a Competent Person at least every 12 months under LOLER 1998, with additional 6-month examinations required where the crane is used to lift persons. Daily pre-use checks should cover wire rope condition, hook and shackle integrity, hydraulic system, outrigger pads, tracks, safety devices and the safe load indicator. All WOLFF Onsite hire cranes are supplied with a current Report of Thorough Examination and full service history. Defects identified in service must be reported immediately and the crane taken out of use until repaired.

Frequently Asked Questions