New generation hydraulic bolt fastening technology deployed at an Australian
iron ore port has enabled operators of a 5000 TPA ship loader to tension bolts
during slew bearing replacement more than five times faster than by using
conventional torqueing or hazardous manual methods.
A total of 72 specially designed Technofast EziTite® Hydraulic Nuts were used
at the Karara Geralton Port to tension grade 12.9 studs that secure the slew
bearing of the loader, which is a vital materials handling installation with long
travel, luffing and slewing capabilities.
The EziTite® Hydraulic Nuts – simultaneously tightened in groups of four to
further enhance precision, speed and safety and cut load scatter – are part of a
globally proven range of EziTite® Hydraulic Nuts used in mission-critical
applications where speed, precision and avoidance of downtime are
EziTite® Hydraulic Nuts are rapidly applied by being placed onto bolt studs and hydraulically actuated to
stretch the bolt to the precise tension required then locking it in place mechanically with a lockring. The
reverse procedure permits equally rapid disassembly when it is eventually required.
Applications range from nuclear and conventional generators through to
rotating, vibrating, turbine, heat exchanger and mineral processing equipment
including stamping, crushing, dragline boom supports, high pressure grind
rollers, hoists and conveyor drives, motors and shells.
“EziTite® Hydraulic Nuts such as those deployed at Karara are ideal for
tensioning all of the studs on a flange, joint or cover simultaneously, loading
entire groups of fasteners at once. This simultaneous tensioning gives an
extremely accurate and even load onto the flange/joint, enhancing its longterm security, safety and reliability,” said Technofast CEO Mr John Bucknell.
At Karara, the EziTite®
nuts were simply placed in position by hand then
groups of four were linked together and pressurized simultaneously, reducing
bolt load scatter and offering dramatic time savings.
“Using torque wrenches, for example, it would have taken about 30 minutes to
tension four bolts, whereas the EziTite®
fasteners completed the task in less
than five minutes,” said Mr Bucknell.
“Also, there are no pinch points associated with Technofast tooling and it
does not need to be handled whilst being pressurised, eliminating inherent
health and safety hazards.
The EziTite® Hydraulic Nuts also overcame bolt load scatter problems
commonly encountered with standard slew bearing replacement procedures
using torque wrenches. Bolt load scatter, due to a single bolt being fastened at
a time, could have caused undue wear on the slew bearing, leading potentially
to downtime on this particular application and on scores of others where slew
bearings are mission-critical.
“Mining and materials handling operations just cannot afford downtime,
production losses and safety risks at a time when they are stepping up output
to compensate for current prices,” said Mr Bucknell. “The mining and
materials handling industries are highly focused on eliminating bottlenecks in
their output systems, especially those created by unnecessary time losses and
ongoing maintenance arising from joint security may be less than ideal.
Benefits of the EziTite® Hydraulic Nut
Reduce maintenance down time.
Improve safety on the job.
Give reliable and precise tensioning.
Fast to fit and remove.
Requires little physical effort.
Is ideal for difficult or confined space
The EziTite® Hydraulic Nut is Ideal where:
Accurate and reliable loading is required on bolting.
Vibrational or torsional stresses are a problem.
Regular maintenance requires repeated adjustment or removal of nuts.
There are confined or difficult nut locations.
Technofast customers globally include Bechtel, BHP Billiton, BMA,
Monadelphous, OneSteel and Rio Tinto.
Loader operations at the $200 million Geraldton Port facility, which consist of a 300m storage facility, a
dedicated berth and the 5000 tph loader.