Crane Turret Head Bolt Torquing

Safety Risks and Inefficiencies

Manually operating the large wrench and extension arm was physically strenuous, and placed the operator in danger of a repetitive strain injury.

The extension bar flexed heavily under force, making accurate application and measurement of torque nearly impossible.

Engineering the Solution

The Norbar mechanical engineering team developed a fully customised Offset Drive (OSD) with an in-built reaction arm that would fit easily into the low-clearance space adjacent to the bolts.

The weight of the OSD was kept to a minimum by fabricating the casing from aluminium, while the gears are tough, high quality machined steel for a long and reliable life.

The OSD combined with a Norbar PTS 1000–200–1000 Nm Pneumatic Tool accurately and easily achieves the required torque of 460 Nm.

The Outcome

The tool and OSD is well balanced for comfortable use, while a safe reaction can be achieved by the reaction arm, keeping hands clear of moving parts and unsafe forces. The whole operation is simplified, with no more need to manoeuvre an unwieldy extension bar in awkward positions.

• Custom solution — designed for maximum power at a minimum weight, the OSD perfectly fits the crane turrets form.
• Efficient — Rapidly torques all 30 bolts, no more manual torquing.
• Safe — Removes the risk of repetitive strain injury, plus hands are kept clear of the bolts. Supportive of continuous improvement strategies and OH&S requirements.