Crusher service firmly bolted on to safety

Using the safest bolting practices has been the key to success for a crusher service specialist based in regional NSW.

Specialised Crusher Services Pty Ltd (SCS), headquartered in Orange, offers an extensive range of technical services and product support in the mining, quarrying and materials-handling sectors. Services are provided specifically for fixed and mobile plant equipment, and include installations, commissioning, preventative maintenance, corrective maintenance, breakdown work, shutdowns, upgrades, inspections, technical servicing and diagnostic fault finding.

In carrying out this work, SCS employs Technofast EziTite hydraulic nuts instead of torque tensioning to help achieve greater safety and speed. Hydraulic bolt tensioning is a quicker, easier and safer way to tighten large bolts to their optimal specified tension. It eliminates the need for torque and for forceful, manual tightening. As the operator can pre-load the exact required tension of the bolt via the amount of hydraulic pressure exerted, it also offers consistent accuracy.

SCS, which typically uses M64 mm and M72 mm EziTites on major connections, aims to promote an incident- and injury-free culture for its clients and staff.

“Leaders in metalliferous mining and in quarrying are super vigilant about quality, compliance, and safety — which is our focus,” said Peter White, Managing Director, SCS.

“A very big part of our work centres on bolting. Whether we are installing a new machine weighing 100–500 tons — or getting an existing one back into profitable production — safety, quality and speed are of the essence.

“Technofast hydraulic nuts remove any hazards associated with using conventional radial torque tooling. Large diameter bolts may require torque input ranging between 10,000–20,000 Nm, and wrenches therefore have considerable stored energy when in use. That’s a lot to deal with if something goes wrong. Changing out just one really big super-sized nut can take two hours using old methods, which is such hard work, while EziTites can get the job done in minutes.

“Plus, some large-diameter nuts — for example, for 160 mm-diameter threads — can be very difficult to remove and install to specification in some complex crusher applications. We have tried multi-stud jackbolt types. But it is just hard work to handle up to 24 jacking screws at 500 Nm,” he said.

Repetitious manual handling is eliminated during installations and removal with EziTite technology, because no large hydraulic torque tooling is required. Safety is enhanced by the hydraulic nuts’ simple operation and speed of removal, which means also that bolt assemblies can tensioned or released in a fraction of the time for a conventional nut and bolt.

“The quality of joint is higher, because bolt assemblies are tensioned with direct-pull elongation, which delivers a more accurate final tension, compared with radial torque,” White said.

“Exactly accurate tensioning, with repeatable results to OEM standards, is important to job quality. This precision can be verified with ultrasonic testing to measure bolt elongation, giving further quality and standards comparability and job measurement traceability. The EziTites give a great result every time.”