Projects id Formidable Social Challenges “Comfort for the Site”— S-FREE™, A Driver of the Evolution of Industrial Electric Wires & Cables

Develop Flexible, Strong and Stress-Free Electric Wires & Cables Story behind the development of S-FREE™ ②

Bunching machine to bunch conductors

Production process of S-FREE™ Vulcanizer to enhance the physical properties and durability of rubber (CCV: Catenary continuous vulcanizer)

Production process of S-FREE
Vulcanizer to enhance the physical properties and durability of rubber (CCV: Catenary continuous vulcanizer)

Extruder for extrusion molding

Extruder for extrusion molding

Stock to quickly accommodate diversified needs

Stock to quickly accommodate diversified needs

Delivered after cutting in accordance with users’ needs

Delivered after cutting in accordance with users’ needs

Birth of welding cables using a high-strength aluminum conductor

The design and development of industrial electric wires and cables are managed by the Engineering Department of the Industrial Wire & Cable Division, in which Shinichi Uehara assumes the responsibility for managing the development of S-FREE products. They are being developed for not only sheathing material formulation, but also conductor materials. A typical example is welding cables using a high-strength aluminum conductor, with the total weight of the cable being considerably reduced. The products were developed as Japan’s first welding cables using an aluminum conductor in place of copper. At manufacturing sites of large structures such as ships and bridges, workers repeatedly carry arc welding machines and welding cables. There was thus a compelling need to reduce the weight of welding cables.

“Among industrial wires and cables, welding cables can use aluminum, but many manufacturers have failed in their development due to the issues of durability and strength. Since the Sumitomo Electric Group has experience of using aluminum for automotive wiring harnesses, we made use of technical knowledge obtained from the experience, developing welding cables about 50% lighter than conventional products. The products help to reduce burdens on workers as well as to extend the service lives of the cables themselves, since less friction is caused even when they are dragged on the ground. Since the electrical resistance of aluminum is higher than that of copper, the temperature of the conductor becomes higher. Therefore, we accommodated this issue by using cross-linked polyolefin with higher heat resistance as a sheathing material. Until we completed the products, we visited customers’ work sites many times to hear their opinions. However, the release of the products is not our goal. We will continue to hear customers’ opinions to see if there is anything we can make better to improve the user-friendliness of the products,” says Uehara.

In order to introduce a wide range of products developed by incorporating users’ opinions in this way and disseminate the development philosophy of the Sumitomo Electric Group, in November 2019, the Group launched the new brand “S-FREE” with the brand concept “Comfort for the site.” The brand name “S-FREE” reflects the Sumitomo Business Spirit (“S”), which values sincerity, and desires to “free” users from stress during work as far as possible.

Shinichi Uehara, Senior Manager, Engineering Dept., Industrial Wire & Cable Div.
Shinichi Uehara, Senior Manager, Engineering Dept., Industrial Wire & Cable Div.
S-FREE™

Production base of S-FREE—Wakayama Plant

The production base of S-FREE is the Wakayama Plant of Sumitomo Electric Industrial Wire & Cable Inc., where more than 300 kinds of S-FREE products of different sizes and items are produced. One of the features of the plant is that it produces not only cables but also sheathing materials such as insulators.

Masaki Tani, the General Manager of the plant, says, “We are now required to improve productivity by realizing speedy manufacturing. Both employees and organizations are flexibly trying new things, such as innovating production engineering including the use of IoT*, information sharing and a new method of quality control.”

Mitsuaki Mukaiyama of the Rubber-Insulated Electric Wire & Cable Engineering Group, Electric Wire & Cable Engineering Department assumes the role of realizing products as physical objects.

“When a new material is developed, we need to determine optimal conditions for stable manufacturing and quality. It is necessary to repeat fine-tuning at the production site while checking the state of the product and considering the ability of the machinery. I feel a sense of achievement when new S-FREE products are released,” says Mukaiyama.

Takayuki Kurisu of the Production Group assumes the responsibility for ensuring stable manufacturing by strictly watching for changes in product quality and hearing the voice of site workers.

“Our group mission is to manufacture stable, high-quality products. We will continue to seek stable quality and efficiency improvement by conducting thorough numerical data management. We also promote the digitization of quality control by using digital devices such as image recognition monitoring systems. However, observation by site workers is the most important. It is also necessary to raise their sensitivity to changes and pass down their experience,” says Kurisu.

Tadashi Nishimura of the Production Control Group, who is responsible for affairs that could directly affect customers, such as delivery time management, stock control and logistics, says that he aims to contribute to the improvement of customer satisfaction by flexibly responding to requests from customers.

“The strength of our company is the availability of a wide variety of product items in stock and the short production lead time. Since our products are high-mix and low-volume, we endeavor to conduct agile production management so that we can deliver products as quickly as possible. We need to flexibly respond to customer requests for sizing and delivery. Not only the features of the products, but all the services we provide are important to contribute to the realization of a comfortable site that S-FREE aims at,” says Nishimura.

Tani, the General Manager of the plant says, regarding their vision for the future, “We aim to develop new markets of S-FREE and gain the top market share in the category of rubber-insulated electric wires and cables. To achieve this, we will evolve our production site so that we can quickly accommodate a wide range of requests from customers.”

* Internet of Things

Masaki Tani, General Manager of the Wakayama Plant, Manager of the Rubber-Insulated Electric Wire & Cable Production Dept., Sumitomo Electric Industrial Wire & Cable Inc.

Masaki Tani, General Manager of the Wakayama Plant, Manager of the Rubber-Insulated Electric Wire & Cable Production Dept., Sumitomo Electric Industrial Wire & Cable Inc.

Takayuki Kurisu, Leader of the Wakayama Production Group, Rubber-Insulated Electric Wire & Cable Production Dept., Sumitomo Electric Industrial Wire & Cable Inc.

Takayuki Kurisu, Leader of the Wakayama Production Group, Rubber-Insulated Electric Wire & Cable Production Dept., Sumitomo Electric Industrial Wire & Cable Inc.

Tadashi Nishimura, Leader of the Wakayama Production Control Group, Rubber-Insulated Electric Wire & Cable Production Dept., Sumitomo Electric Industrial Wire & Cable Inc.

Tadashi Nishimura, Leader of the Wakayama Production Control Group, Rubber-Insulated Electric Wire & Cable Production Dept., Sumitomo Electric Industrial Wire & Cable Inc.

Mitsuaki Mukaiyama, Leader of the Rubber-Insulated Electric Wire & Cable Engineering Group, Electric Wire & Cable Engineering Dept., Sumitomo Electric Industrial Wire & Cable Inc.

Mitsuaki Mukaiyama, Leader of the Rubber-Insulated Electric Wire & Cable Engineering Group, Electric Wire & Cable Engineering Dept., Sumitomo Electric Industrial Wire & Cable Inc.

Wakayama Plant of Sumitomo Electric Industrial Wire & Cable Inc.

Solution Case 01
Reduce Burdens on Shipyard Workers
—S-FREE Welding Cables Using a High-Strength Aluminum Conductor