Illustrator Hiroki Tsuboi visits Sumitomo Group
Sumitomo Riko Hosetex, Kyoto Plant

Established in 2008 as TRI Hose Sales Co., Ltd. and renamed Sumitomo Riko Hosetex in 2016,
this plant is spearheading global development of the Sumitomo Riko Group’s industrial hose business.

Why does the production facility have to be three times as long as the hose? Why does the production facility have to be three times as long as the hose?

While pursuing efficiency through automation, some manufacturing processes are performed manually in the true monozukuri spirit (top). The Kyoto Plant at Ayabe is on a 130,000 m2 site amid forest-clad countryside (bottom).

When hoses are mentioned, I think of the garden hose I use for watering plants or for washing my car. Unlike those familiar home-use hoses, the world of industrial hoses is varied and dynamic! Hoses are used for myriad purposes—feeding raw concrete at construction sites, discharging slurry in tunnel excavation, feeding liquid nitrogen on fishing boats to flash freeze tuna, to mention a few. Industrial hoses are essential kit in fields of every description.

Our destination is Sumitomo Riko Hosetex in Ayabe City, Kyoto Prefecture, one of the largest plants in Japan for manufacturing industrial hoses. The plant concentrates on two types of industrial hoses: hydraulic hoses and feeder hoses.

Hydraulic hoses are indispensable for fork lifts, excavators, and all sorts of other gear used in construction and civil engineering. Feeder hoses are used for conveying an extraordinary range of materials, everything from concrete and slurry to foodstuffs.

As you can imagine given the multitude of applications, the number of different kinds of hoses is mind-boggling. When I naively asked how many there were, our hosts at Sumitomo Riko Hosetex exchanged bemused glances. “There are so many that we have never actually counted them…” said Mr. Hirokazu Ninagawa, President of Sumitomo Riko Hosetex. “For a start, there are at least 100 kinds of hydraulic hoses just in terms of the combination of the working pressure and the external diameter. Hoses are also classified by applications, such as for construction machinery or industrial equipment, and so there are about 400 to 500 different kinds of hoses. In addition, if you counted the finished products with fittings, the number would rise to tens of thousands or even hundreds of thousands,” continued Mr. Ninagawa.

If you think about it, it’s not such a big surprise. Sumitomo Riko Hosetex is such a powerful contender in the world of industrial hoses because it can exploit Sumitomo Riko Group’s prowess in polymer materials technology for flexible compounding of materials for hoses. More than 10 rubber-based materials are used, such as carbon black for greater strength and oil for flexibility, to achieve the optimum compounding attuned to the customer’s precise needs. The variations are virtually infinite.

We are accelerating global business development from Ayabe in Kyoto Prefecture! We are accelerating global business development from Ayabe in Kyoto Prefecture!

Many hoses are purpose-built, such as for construction machinery and for aerial refueling of the JASDF (top). This hose with a narrow section is designed to prevent the spraying of excessive quantities of raw concrete (rightbottom).

Struck speechless by this seemingly boundless universe of hoses, I headed off to see for myself how these things are made. The plant in Ayabe City dates back to 2013. The decisive factor for selecting this site was its large size. The plant has a floor area of 71,000 m2.

First stop was the enormous area where hydraulic hoses are manufactured. Syuji Ikaga, Director of Sumitomo Riko Hosetex and General Manager of the Kyoto Plant, explains: “In the manufacturing process, the hose is built up layer by layer around a mandrel. In the manufacture of feeder hoses, plastic mandrels are the norm. But for hydraulic hoses for heavy equipment, we use steel mandrels capable of withstanding extreme pressure. As steel mandrels are not flexible, the production line must be straight. Whereas at the previous plant, manufacturing was limited to hoses no more than 20 meters in length, here at Ayabe the maximum length is 60 meters, greatly boosting productivity.” For the manufacture of 60-meter hydraulic hoses, you need a production facility whose length is roughly three times the hose length, which is equivalent to two end-to-end football pitches (See the column below). This makes the Ayabe production facility one of the largest of its kind in the world.

Wires and cords are wrapped around plain rubber hoses for reinforcement.

In this process, melted rubber is pressed around the steel mandrel to build the base layer of the hose.

Why does the production facility have to be three times as long as the hose?

In terms of its basic structure, a hose has three elements: an inner rubber tube is wrapped with a reinforcement layer, such as wire or canvas, which in turn is covered by an outer rubber layer (left-handupper diagram).

In the hydraulic hose manufacturing process, a steel mandrel is selected from a stock of mandrels and fed toward the other end of the plant. Rubber is wrapped around it as it is moved back from the other end of the plant. The rubber-wrapped mandrel is also wrapped with reinforcement layers, which are followed by an outer rubber layer. Then the hose passes through the vulcanization process to cure the rubber. Finally, the mandrel is removed from the hose. So the production facility needs to be roughly three times as long as the hose (right-handbelow diagram).

Hose structure Manufacture of a hydraulic hose Hose structure Manufacture of a hydraulic hose

Next stop is the adjacent area devoted to the manufacture of feeder hoses. What caught my attention here was the sight of employees manually wrapping reinforcement around rubber hoses. All the processes for hydraulic hoses are automated. Why not for feeder hoses?

“It’s difficult to automate all the processes for feeder hoses because customer needs are so very wide ranging,” says Mr. Ikaga. “A customer may, for instance, request additional strength or greater flexibility in a particular section of a hose. For hoses used for spraying raw concrete, the final section of a hose should be lightweight so it is easier for a construction worker to hold. To precisely meet these needs, meticulous attention to detail is a must. For example, reinforcement should be wrapped more densely in one place or a different material should be used for a particular portion. Craftsmanship makes all the difference,” says Mr. Ikaga.

In front of me, an employee is wrapping reinforcement around a hose. It requires considerable skill to wrap the reinforcement without any gap or overlapping. This manual process is advantageous in that the resulting hose has an extremely smooth surface. I was surprised to learn that, although hoses are often used in severe environments, their manufacture involves great attention to detail, fine judgment, and skill.

Mr. Ikaga continues: “Our mission is to offer high-performance, high-quality hoses capable of enduring challenging conditions. In particular, hydraulic hoses used at construction sites must perform in a rough-and-tumble environment in which hoses that are not up to the job will soon be damaged. If that happens, construction may be delayed or oil spillage may damage the environment. In the worst case, the lives of workers may be put at risk. Our hoses are designed and manufactured so as to help ensure safety at construction sites worldwide.”

Grasping a finished hydraulic hose, I can feel its supple toughness as something you can count on even though it isn’t highly visible. These hoses embody a wealth of technology and experience.


What a surprise! Some things are still best done by skilled hands.
Because feeder hoses are many and various to meet diverse needs, they are custom-made.
Every hose has a serial number. Customers sometimes ask for the same person to make the hose they order.
True craftsmanship! What if I change my penname to a number? Are you really going to do that?

Editor’s note

Sumitomo Riko Hosetex is based in Ayabe City, Kyoto Prefecture, about an hour from Kyoto Station by express train. Previously, Sumitomo Riko’s industrial hose division manufactured hoses at two plants: one in Komaki City, Aichi Prefecture, and the other in Matsusaka City, Mie Prefecture. However, in view of the need for a larger site to enhance productivity, the Sumitomo Riko Group made Ayabe the base for its hose business in 2013. Touring the plant, we were struck by the rhythmic progress of the hose manufacturing process in which a steel mandrel is wrapped with rubber, wire, and other materials. Mr. Tsuboi found it fascinating. While feeling the texture of the rubber, he asked our guides plenty of questions.

Besides the sheer scale of the plant, what impressed us most is that small-lot production of a great variety of hoses is achieved through the combination of the company’s unique rubber compounding technology and the employees’ expertise in applying the wire. Hoses manufactured at Ayabe are fulfilling essential roles on construction sites and at disaster-affected areas around the world. The extent of the craftsmanship underlying the entire operation was a revelation that made our visit especially memorable.

Sumitomo Riko Hosetex looms large at Ayabe Industrial Park, which is home to numerous factories.

Mr. Tsuboi receives explanation while holding a hose.

Number (Manga Reportage "Visits to Sumitomo Group")