Grasping the thread

With increasing pressures from factors such as timesaving, foreign object debris and reusability, effective mechanical thread locking is a challenge faced by many manufacturers

As new products are developed, it’s worth considering some of the challenges and what fresh options are available to manufacturers, as cost is no longer the overriding factor. Certainly, when selecting either a mechanical or adhesive thread locking solution, there is an array of factors to consider:

Excessively high or low temperature can restrict the alternatives available. For example, temperatures in excess of 150-200 degrees seen in industries such as power generation, transport and aerospace would limit the use of any thread locking method that involves plastics, such as nylon-insert lock nuts or liquid thread lockers. Chemical and corrosion resistance can also affect the most suitable method of mechanical thread locking.

Looking at the automotive or chemical processing industries, for instance, certain materials like oils can hinder or completely stop thread locking adhesives from curing anaerobically. Likewise, for industries that have oxygen-rich environments, such as medical equipment and aerospace, liquid thread locking solutions are really not an option.

Some applications require that an assembly is dismantled, and the thread lock removable and reusable. For example, the plant and machinery market often stipulates that thread locks needs to be removed and reused for ongoing servicing and maintenance on machines, ruling out the solutions that can only be used once and disregarded.

Where reusability is a requirement, removal tools also have to be considered, which can bring additional cost and resource implications. In motorsport, for example, quick and efficient disassembly is integral to the decision of which thread locking solution to use.

There is a plethora of thread locking solutions in the marketplace, each with its own merits and drawbacks. The market has seen various developments in some of the key solutions, including formulation changes to anaerobic liquids, mechanical split pins, torque prevailing nuts and nylon-insert lock nuts.

At Advanex, for example, its strong foundations in spring technology and expertise have been employed to develop LOCKONE – a special spring device that prevents nut and joint bolts from loosening though vibration. LOCKONE is said to be suitable for M5 to M24, and is applied using a normal spanner or socket wrench. When the nut is tightened onto a bolt, it grips the bolt thread, preventing the nut from loosening.

According to the company, initial tests show that LOCKONE outperforms other locking methods, with the added benefits of being reusable and non-destructive, on account of its foreign object debris (FOD) free design, states Advanex. “Manufactured in stainless steel, LOCKONE performs well at high temperatures and in corrosive environments, and has been well received in industries such as aerospace, construction and transport. As LOCKONE can be removed using standard tools, it does not require expensive tooling for removal," it says.

LOCKONE has performed well in Japan and also passed impact vibration testing for the US aerospace standard, while, in China, it is undergoing testing for use on the high-speed railway.