Star bolting performance puts safety and efficiency first at landmark project

Compact and powerful hydraulic bolting technology is paying safety and efficiency dividends in the construction of the landmark new multi-use entertainment facility being built atop The Star Casino in Sydney.

The 2.7kg rigid steel S series torque wrench from the Enerpac Professional Bolting Range was selected by ICMP Steel Structures Pty Ltd for the Brookfield Multiplex MUEF project, which will feature a eye-catching emerald roof design designed to make a striking addition to the skyline of its location in harbourside Pyrmont.

The ergonomic torque wrenches are designed to enhance workplace safety and efficiency by replacing slower methods, such as pneumatics, or manual methods, such as flogging spanners, throughout industries such as construction, engineering, mining and energy, oil and gas, and infrastructure and water and waste water. They are particularly suitable for applications where many bolts must be tightened to precise uniform torques for structural integrity and safety.

Brookfield Multiplex’s 80X40 metre structure – scheduled for completion by January 2013 - features more than 12,000 bolts to be tightened to tension-bearing (TB) status in the prefabricated trusses and associated steelwork that must be rapidly assembled on-site to a precise schedule and according to exacting bolt tensioning standards specified by Standards Australia.

“We specialize in innovative construction methodologies, management and planning and are constantly looking at ways to optimize our performance,” said ICMP Associate Mr Chris Mathews. “We chose this hydraulic torque wrench technology because it provides great strength in places that are hard to access. We haven’t previously had this many TB bolts to deal with at once. We needed technology that would save manpower, do the job very safely to the high standards we share with Brookfield Multiplex, and provide us with the grunt to do the job properly and precisely.

“The normal pneumatic bolting gun would be right at the limit of its performance for this job, whereas the load on the Enerpac torque wrench and pump is minimal,” said Mr Mathews, who selected an Enerpac S1500 torque wrench from the Enerpac S Series of double-acting square drive hydraulic torque wrenches, weighing between 2.7 kg to 31 kg, with outputs of 1898-34,437 Nm. The S1500 provides up to 1898Nm (1400 ft lbs) of torque at 700 bar pressure with a typical socket size range of 15 – 50mm (5/8 - 1 7/8 in). The wrench is actuated by an Enerpac ZU4 series electric pump engineered to save power and increase reliability by reducing the number of moving parts it incorporates.

In addition to easy handling and safe ergonomics, the compact Enerpac torque wrench offers improved access to bolts within less accessible areas of the prefabricated girders and trusses

“Where tight access is an issue, the Enerpac cassette design and separate pump is more favourable than the normal gun,” said Mr Mathews.

To achieve consistent torque values and meet the requirements of Australian Standards, each TB bolt is tightened to the snug position, then, using the torque wrench, advanced from this mark by a further one third of a turn.

“This torque wrench method of achieving the result we want is far superior – whereas conventional guns were on the limit, this bolts quickly and precisely for us, said Mr Mathews. “Speed is an issue to us, because we pre-assemble trusses involving hundreds of bolts at a time and the job has to be completed to a high standard before we move on the to the next stage.”

To give easy access to bolting tasks, the nose radius of the S range is between 23-63.5mm, with the square drive ranging from three-quarters to two-and-a-half inches. Enerpac Territory Manager NSW Jason Agatsiotis says the S series’ single 360º hydraulic swivel manifold increases wrench and hose manoeuvrability, making it ideal for construction and maintenance work. Features of the range include:

  • Rigid steel design guarantees durability, reliability and safety.
  • Push button square drive release for quickly reversing the square drive for tightening or loosening
  • Fine tooth ratchet prevents tool "lock-on"
  • 360 degree swivel manifold with screw lock couplers
  • Optional Allen key drives 14-85 mm, 1/2 - 2 1/4 inch
  • Fast operation due to the large nut rotation per wrench cycle (35 degree) and rapid return stroke
  • Constant torque output provides high accuracy (±3%) across the full stroke

Enerpac torque wrenches, including the W hexagon cassette range, are designed using state-of-the art CAD techniques to deliver the most advanced hydraulic torque wrenches on the market, says Mr Agatsiotis.The high-efficiency design of the ZU4 series electric pump used with the S series has higher oil flow and by-pass pressure, runs cooler and requires 18 per cent less current draw than comparable pumps.

BROOKFIELD MULTIPLEX AUSTRALASIA. established in 1962, the Brookfield Multiplex business includes Construction + Development, Engineering + Infrastructure and Infrastructure Services, with a current workbook value of US$5.4 billion across 28 projects, spanning a variety of sectors including commercial, infrastructure, health, retail, residential and education.

ICMP specializes in innovative construction methodologies, management and planning. ICMP Associate Mr Chris Mathews can be contacted on 61 (0) 414 447 517.