September 30, 2008


Major Manufacturer Making Improved Bearings that Minimize Energy Loss and Environmental Impact -- NTN Corporation.

Keywords: Newsletter 

JFS Newsletter No.73 (September 2008)
Toward a Sustainable Japan--Corporations at Work Article Series No.73

The bearing is a humble but essential part that supports rotary motion and reduces friction in the many machines and devices used daily around the world. Its structure is simple, consisting of four kinds of parts: a large outer ring and a small inner ring with a rolling element, such as balls, and a retainer cage in between them. Smoothly finished bearings help reduce friction in the rotary motion section of machines and avoid wasting energy.

The first bearings in recorded history were used in ancient Egypt, as shown in a wall painting depicting people pulling a heavy stone with a rope and placing many rolling logs underneath as it moved. This demonstrates the principle of the bearing exactly. The basic structure of the current design was developed by Leonardo da Vinci about 500 years ago, and as the design of machinery advanced, so did the form of bearings. The design was substantially advanced when bearings began to be used in automobiles, an innovation of the nineteenth century. They are now indispensable parts of all kinds of machines and invisibly support our daily lives.

The NTN Corp., based in Osaka, was established as a bearing maker in 1918. The company has continued to grow as a comprehensive manufacturer of precision equipment, including bearings, with its expertise and know-how, while it continues its basic research.

Bearings account for more than 60 percent of the company's sales, and are used in a wide range of business areas, ranging from automobile engines and transmissions, rail cars, hard disks in personal computers, and wind turbines to industrial equipment at construction sites. The way NTN sees it, by producing precision bearings, it is contributing to protection of the global environment with an energy saving eco-product.

Contributions to improved use of natural energy sources

The demand for renewable energy such as wind power to curb global warming is at an all-time high. The harnessing of wind power, in particular, is developing as a relatively efficient technology that can convert wind energy into electricity now at a maximum of about 40 percent. In Japan, both generation capacity and the number of turbine installations are rising, reaching over 1.67 million kilowatts from 1,409 units by the end of March 2008. NTN places "coexistence with the global environment" as one of its priority management issues and actively works on developing more environment-friendly products. It is also committed to contributing to the ongoing improvement of wind power generation to further reduce environmental impacts.

Bearings play an essential role in wind power generation equipment. For example, bearings developed and manufactured by NTN are used in the rotary shaft that absorbs the rotation from the turbine blades driven by the wind and in the gearbox at the root of the blades to adjust the angle of the room called the nacelle, which contains major devices such as a generator and the generator body.

Wind power generators are required to run stably for a long time with as little maintenance as possible, because most of them are erected in remote areas such as along coastlines and on highlands. As higher-power and larger-sized wind power generators have been developed, the need has increased for ultra-sized, reliable, and durable bearings to endure enlarged loading.

Kiyoshi Nakanishi, general manager of NTN's Environment Management Department, showing his enthusiasm for the development, said, "Bearings are responsible for converting wind power into energy efficiently. We would like to proactively address increased demands and diversified needs."

Meeting new challenges in the medical field with bearings

Improved bearings can contribute not only in the field of renewable energy but other areas, too. For example, in cooperation with Terumo Corp., a major medical equipment manufacturer, and Kyoto University, NTN developed a small, implantable artificial heart pump. With NTN's technology, the pump is able to aid a deteriorated heart in supplying sufficient amounts of blood throughout the body.

One of the hurdles in developing the pump was the structure of its bearings. If a bearing that sustains a bladed wheel that pushes blood through the whole body has an ordinary structure, one with a ring and ball bearings, it may hinder blood circulation and may destroy red blood cells because of friction. To solve this problem, NTN developed a contact-free technology that levitates the bladed wheel with electromagnetic force. The three parties cooperated on making various prototypes and conducted a series of motion experiments. In 2004, a clinical experiment started in Germany, and the product was commercialized for the European market in 2007. In Japan and the United States, they plan to conduct clinical testing.

"Initially, putting mechanical equipment into a body was hard to be accepted. But after some trial and error, we have come to this stage. We would like to contribute to the development of other types of medical equipment," said Takatoshi Saiki, general manager of NTN's Corporate Social Responsibility Department.

Towards zero industrial waste and emissions

Another area NTN is also working proactively in is addressing the goal of zero industrial waste emissions. In the finishing stage, top-quality bearings need high-precision processing, such as honing their surfaces and polishing them like a mirror. Formerly, the residue created by this process, iron powder mixed with grinding fluid, was considered unusable sludge, and NTN used to pay to dispose of it as industrial waste.

To do something about the waste sludge, NTN first developed equipment to solidify it, which separates the sludge in the bearing production process and isolates the metals in it. The solidified metal, made into forms the size of an ice hockey puck, can be recycled as raw material in steel making, and the separated fluid can be reused in the honing line. Since its development in 2002, NTN has introduced the equipment into its group companies. In 2007, the total amount disposed was 923 tons and the recycling rate was 98.5 percent, compared to 5,465 tons of annual waste disposed and an 87 percent recycling rate in 2001. The equipment has played a big role in moving closer to zero industrial emissions. At the same time, it has contributed to cost reductions.

The equipment was also released into the market, including being sold to competitors, and it has already been introduced in many kinds of factories such as machine parts makers and automobile manufacturers, thus contributing further to the achievement of zero emissions initiatives in the industry.

NTN targeting environmental challenges in its supply chain and global cooperation

In addition to contributing to zero emissions initiatives, NTN is making other concerted efforts in improving its environmental management by practicing green procurement, for example. To promote environmental management throughout its whole supply chain, however, NTN and its partner companies, such as parts suppliers, are required to work together. Therefore, NTN has recommended to its major partner companies that they acquire an environmental management system certificate by 2010 such as ISO14001.

Some of NTN's partner companies, however, are small family-run businesses. For these, NTN introduces them to the Eco Stage system, a Japanese private certification system that simplifies ISO14001 for small- and medium-sized businesses, or the Eco Stage Introductory Version, which is an environmental certification system that NTN originally developed for businesses that find the Eco Stage standards still hard to meet. It was adopted in 2004 by the Eco Stage Institute as a trial-level certification system. In the case of businesses that find it difficult to meet the criteria because of lack of manpower or financial support, NTN tries to help them get certified by visiting each in the field and offering individual support.

About Japanese private certification systems that simplifies ISO14001

"Some companies are also promoting environmental management throughout the whole supply chain," said Kiyoshi Nakanishi, "but our uniqueness is that we support each factory individually and try to respond to its specific needs. Our method requires a lot of work, but we believe it is important to help expand environmental management to all companies willing to cooperate, including small-size businesses."

With the aim of increasing the incentives for improving environmental management along the whole supply chain, NTN established the "NTN Environmental Grand Prize" to reward partner companies that have actively challenged themselves to acquire certifications or have shown environmental improvement. Among 281 major cooperative companies, 86 percent of them have already been certified and are making efforts to reduce the environmental load throughout their whole supply chain.

Another important task, NTN believes, is to collaborate with others in the global bearings industry in promoting activities that contribute to the environment. As the average person is not aware that rolling bearings are inherently ecological products that contribute a great deal to protecting the environment, NTN joined in the work of editing and publishing a brochure titled "Bearing is Ecological" by the World Bearing Association (WBA) in May 2008. The WBA was founded by the Japan Bearing Industry Association, to which NTN belongs, the American Bearing Manufacturers Association, and the Federation of European Bearing Manufacturers' Association in September 2006 with the aim of tackling global issues such as environmental problems.

World Bearing Association

Bearing is Ecological.

"This brochure is the first outcome of the collaborative work by Japan, the United States, and Europe," Nakanishi said. NTN intends to achieve environmental contributions not only in its local supply chain but also in the global bearings industry.

(Written by Kazuko Kojima)