The HARDLOCK Nut has been used successfully in many applications worldwide for more than a decade

The HARDLOCK Nut has been used across many industries including railways, civil engineering, telephone, radar and power masts, towers and pylons, wind turbine towers and masts. Other industry sectors include highways, bridges, skyscraper buildings and steel towers.

HARDLOCK Nuts are specified by manufacturers in all these industrial sectors:

Railways including rolling stock, points & signalling, infrastructure and electrical installations.

Structural building steel work

Safety critical machinery

Shipbuilding

Automotive

Mining and quarrying machinery

Before
When a train passes, a force of 500G is applied to the switch, and even specially shaped double nuts used on the movable parts can become loose on a daily basis.
While the switch (movable part) is essential to maintain the track gauge, it is extremely difficult to maintain the gauge of the track while preventing loosening.
After
By using the HARDLOCK Nut, the maintenance cost associated with inspection and re-tightening was successfully reduced.
The HARDLOCK Nut successfully maintained the gauge of the track and prevents loosening simultaneously. As a result, the HARDLOCK Nut has been adopted by all railway companies in Japan.

For more information about the Hardlock’s rail & track applications please click here.

Before
In high speed rail cars, repeated impact of the rail coupling causes the nut to loosen and may even risk detachment.
Damage to friction ring also causes the nut to loosen.
After
By using the HARDLOCK Nut, even under repeated impact, loosening is prevented and detachment does not occur.
Breakage of the friction ring is eliminated by using the HARDLOCK Nut and has been adopted by many rail car manufacturers.
Before
Hydrolic breakers used at large mines and quarries used double nuts fastened with high torque.
Severe vibration caused loosening on a daily basis.
After
HARDLOCK Nut was used to overcome nut loosening at the appropriate tightening torque.
The HARDLOCK Nut works with standard thread forms, and therefore no bolt specifications changes were needed so the HARDLOCK Nut could be implemented quickly.
Before
Wind turbine towers stand in areas of strong wind, due to irregular stresses caused by strong wind load, double nut and spring washers are frequently used to prevent loosening.
Nylon nuts are used to fasten the cable rack wiring inside the tower and the ends of the ladder, but loosening still occurred due to the micro vibrations caused by the blade rotation.
After
By using the HARDLOCK Nut, the correct torque and bolt load could be managed at each of the fastening points.
As a result, the frequency of routine maintenance was extended and the costs were significantly reduced.
Before
Steps to prevent loosening had been used including double nuts and the use of spring washers but vibrations during transportation and micro vibrations that occur after installation had resulted in frequent loosening.
After
By switching to the HARDLOCK Nut, all problems related to loosening were completely solved.
Because loosening does not occur, both the number of inspections and re-tightening work has been significantly reduced resulting in labour savings.