The PB17B-3R-II is a spider concrete placing boom — a free-standing, easily relocated boom that sits on its own inclined-outrigger base, spreads concrete over a 17 m radius, and is lifted to the next position by the site's tower crane when a pour is done. Unlike a climbing boom, it does not attach to the structure or the formwork; it stands wherever it is set down, legs splayed for a stable, fixed working state, then folds and travels light. At just 6,500 kg, and with a heaviest single piece of only 1,520 kg, it is the most portable boom in the TRUEMAX range — a crane can pick it up and move it around the deck with ease.
That mobility makes the PB17B-3R-II the tool for spreading concrete across slabs and floors where the placing point has to move around the site as the pour progresses. It is fully hydraulic, with a three-arm R-fold boom and 360° slewing driven by a self-locking turbo worm gear that holds the boom steady at any angle. Like every placing boom it is fed by a separate concrete pump rather than pumping itself. It runs on a 380V/50Hz supply with a 5.5 kW motor, and is built and tested at the TRUEMAX factory in Haining to ISO 9001:2015 and CE standards, within a placing-boom line exported to more than 120 countries.
1. Inclined-outrigger spider base — The splayed-leg base sets the boom down firm and fixed on a slab without anchoring into the structure, then lifts clear for relocation — the defining feature of a spider boom.
2. Lightest, most portable in the range — At 6,500 kg total and a maximum single lifting unit of just 1,520 kg, a tower crane can reposition it around the site quickly between pours.
3. Three-arm R-fold hydraulic boom — Three R-fold arms, fully hydraulic, open for a 17 m placing radius and fold compactly for crane handling and transport.
4. Full 360° slewing — The boom rotates a complete circle to cover the area around its set-up point from a single position.
5. Self-locking worm-drive slewing — A turbo worm-gear slewing drive turns smoothly and holds the boom steady at any angle without drifting — well matched to a light, frequently-moved boom.
6. Radio and cable remote control — Two operating modes — wireless radio and cable remote — let one operator place concrete from the clearest vantage on the slab.
7. Compact 17 m reach — Sized to cover a working bay from each set-up, then relocate, rather than carry a longer, heavier boom than the area needs.
8. Quality components — Hydraulic and electrical parts from well-known international brands for stable, reliable operation.
