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Products (Machinery - Industrial parts)

Hardlock Industry Co. Ltd.:Hard Lock Nut


Screws have been used in Western civilization since such ancient times that their origin is unclear. The metal bolts, nuts, machine screws, wood screws and similar fastenings widely used today likely appeared as early as the 16th century.
 Demand for bolts, nuts and similar fastenings increased drastically in conjunction with the rise of the Industrial Revolution in the second half of the 18th century.

Despite this long history, it was only very recently that the age-old problem with screws – they come loose – was solved.
A screw is something that is used by ordinary people in their daily lives, but it’s actually extremely difficult to make a screw that will never come loose: that requires both appropriate design and suitable fastening method to be established with considerable accuracy. Loosening can even occur almost instantly when the screw is subject to intense vibrations, which has meant an endless series of accidents caused by the loosening of screws used in machine tools or transportation equipment. 

Here we introduce the Hard Lock Nut, manufactured by Hardlock Industry Co. Ltd.. This is a revolutionary product which uses a unique wedge structure to finally realize the ultimate screw: one that never loosens.
Nuts play an important role in keeping screws from becoming loose. Until now the nuts available have not been powerful enough to prevent the inevitable loosening of screws over time. The Hard Lock Nut, however, promises something different.

The National Aerospace Standard (NAS)3350 and NAS3354 vibration tests are said to be the most stringent of all tests carried out on screws, and in general a screw fixed with a standard nut will loosen within 20 seconds.
With the Hard Lock Nut, however, the screw did not loosen for more than an hour while being subject to the vibration testing.  

Today, as testament to its superior performance, the Hard Lock Nut has been introduced into diverse sectors of Japan’s industry; it is used widely in transportation equipment including railways, vehicles, marine vessels and aircrafts, and in construction including highways, bridges, public works, towers, power plants and dams, and in production facilities from key industries including iron manufacturing machines, press machines and crushers. 

Overseas, it has been widely adopted, for example in rapid transit railways in Taiwan, the U.K. and Germany, and in the machine tools and products of multiple American and European manufacturers.
This impressive portfolio indicates how the Hard Lock Nut is used to ensure product safety all over the world.

Quality that can never be copied

Today, as many Asian countries are pushing forward with rapid industrialization, there is a growing trend toward manufacturing products based on Japanese product standards, in an attempt to introduce outstanding Japanese technology to domestic industry. 
Although there are those small and medium companies which, apprehensive of a technology drain from Japan to overseas, work to keep their technologies and products as confidential as possible, Hardlock Industry Co. Ltd. by contrast is active in seeking to extend its overseas operations. 
This is because the company can be confident that Hardlock Industry products can never be copied. 

As mentioned earlier, it is easy to think of screws and nuts as having very simple structures, but in truth they are extremely precise components. 
Only Hardlock Industry is capable of producing, in bulk, a stable supply of nuts with the kind of precision required. 
They do this through an integrated manufacturing process, made possible by the use of special metallic molds and unique machine tools, specially designed and built by Hardlock Industry, as well as the comprehensive control of the range of error, in units of microns. An external shape may be copied with relative ease, but it is the outstanding quality that really makes the product; and this is much harder to imitate. This is where the strength of the Hard Lock Nut lies. 

The idea behind the Hard Lock Nut can be traced back to kusabi, wedges used in the traditional architecture of Japan, in which screws were not used. 
This wedge was driven into any space remaining where other components had been joined together by one being inserted into the other, in order to strengthen the joint at that point. 
The Hard Lock Nut applies the principle of this wedge to the screw; it inserts a wedge-like structure into the space between the thread and the groove. Despite the simplicity of its structure, its development took about 15 years. The Hard Lock Nut is the result of much research, precision design and processes that made it possible for the invention to be patented. 
Today, the Hard Lock Nut enjoys a reputation for outstanding performance, unmatched by any producer anywhere in the world, including the technological superpower of Japan.

Reliability launching out into the world

Hardlock Industry’s nut business began to grow rapidly in the late 1970s, thanks to the decision, made in 1976, to use the Hard Lock Nut in electric power equipment for a major private railway company in west Japan. 
Later, the Nut was adopted in railways in Poland, China and Korea, was officially certified in Australia and the U.K. and was even introduced as highly effective in a British Broadcasting Corporation documentary. 

The Hard Lock Nut was used in the Akashi Strait Bridge, the world’s longest suspension bridge, and the Tokyo Sky Tree, the world’s highest standalone radio tower. Hardlock Industry has also been approached to supply the Hard Lock Nut for use in U.S. space shuttle launchers, marine excavators, Boeing aircraft in the U.S., and Rolls-Royce in the U.K.. 

Hardlock Industry is not just interested in the pursuit of safety; weight reduction is another key goal. The weight reduction for the Hard Lock Nut achieved thus far is 14.8g, from 18g down to 3.2g, about one-sixth of the original weight. 
This indicates how Hardlock Industry, by now a globally recognized enterprise, continues to concentrate on the development of its products, while simultaneously working to promote the use of the Hard Lock Nut, shown to be able to considerably reduce maintenance and checkup cost as well as losses that occur as a result of loosening in ordinary screw applications.

Today, there is increasing demand for products that can guarantee safety in the face of major earthquakes and natural disasters. 
Hardlock Industry will doubtless continue meeting this demand in the years to come, as it continues to challenge itself to provide safety and security solutions for the entire world.
(Hardlock Industry Co., Ltd.)