Technofast Addresses Giant Nuts Challenges for Heavy Industries
Heavy industries such as mining, shipbuilding, and power generation have specific requirements for extremely large nut and bolt fasteners. These pose huge difficulties with applying specified bolt tensions because, for example, a nut weighing thirty kilograms will not be tightened with hand tools. Such nuts are installed or removed with sledgehammers, stud heaters, or torque wrenches, which can weigh as much as the person using them. Installation of such large fasteners is extremely time-consuming, can be hazardous to workers, and may not result in even tightening of every fastener to the precise tension required for long and safe joint life. Disassembly for maintenance can be equally slow, hazardous, and damaging to equipment and production schedules.
A proven best-practice solution is the use of the Technofast EziTite® family of hydraulic fasteners. Assembly and removal times are 15-20 times faster than conventional means in structural steel fabrication, and cut downtime while enhancing safety and joint precision. The fasteners are so efficient and swift in operation – including in hazardous, hot, underground, and confined spaces – that they are used in nuclear energy plants where short exposure times to workers are of critical importance. Technofast fasteners are also commonly used in some of the largest and most difficult critical bolting applications in machinery: in electricity generation, steel fabrication in mining, quarrying, materials handling and high temperature processing applications throughout Australasia, SE Asia, and the USA.
“EziTite technology replaces conventional mining and energy methods in situations where time is money, and safety is paramount,” says Technofast Founder and CEO, John Bucknell. Technofast also retains the NQA-1 nuclear manufacturing standard for supply to the Korean Hydro and Nuclear Power (KHNP) organization and supplies operationally critical bolting for their nuclear fueled electricity generating plant. Technofast EziTite was used to tension boiler feed pump bolting at electricity generating plants in South Korea. The application involved 12 large M110 X 4.0 studs, which were 110mm (4.33in) in diameter with an outside diameter of 200mm (7.87in). EziTite® TR High Temperature Hydraulic Nuts were used as an alternative to the former method of large torque wrenches weighing more than 125kg. The Technofast EziTite method resulted in a total installation time of approximately one to two hours, using two personnel, compared with eight hours and three or four personnel using the previous method.
“Large nuts of this diameter can require terrific torque forces to achieve the desired tensioning or require multiple jack bolts on each stud to bring the job within the power range of hand tools for metal work. Really big nuts – such as those widely used in mining (including mining plant and equipment), energy, and other industries – can easily have 24 jack bolts in total per nut, as did the nuts at the electricity generating plant in Korea,” says Bucknell. “Also, when jack nut fasteners need to be removed, operations staff must untighten the jack bolts in a strict sequence to avoid failure. If they do not, individual jack bolts can break and then the entire assembly would need to be cut off.”
