Mitsubishi weighs in to rubber mixer market

Based on article published in the March/April edition of European Rubber Journal magazine

London -   Japanese machinery company Mitsubishi Heavy Industries Ltd (MHI) – well established as a maker of curing presses and other tire and rubber equipment – is trying to carve out a new position for itself as a supplier of intermeshing mixers for the tire industry.

About five years ago, Hiroshima-based MHI developed a new rotor for the tire industry. The design is based on experience built up over many years as a supplier of intermeshing mixers to non-tire rubber companies, including Mitsuboshi, Nishikawa, Tokai Rubber and Toyoda Gosai.

“We were a latecomer in the mixing area,” explained Jun Umemura, deputy manager, rubber & tire machinery sales & marketing section, Rubber & Tyre division at MHI. “We started making mixers that Kobelco – the largest rubber machinery maker in Japan – does not [focus on], which means intermeshing.

“But as tire makers do not usually buy equipment from a company without references we started with non-tire companies.”

But the recent trend towards low rolling-resistance tires employing high-silica tread compounds has created an opening in the tire market for MHI, particularly in Asia.

While tire makers in Europe, such as Michelin, Continental and Pirelli, largely switched to intermeshing mixers many years ago, tangential mixers have remained the technology of choice for Asian companies such as Bridgestone, Sumitomo, Yokohama and Nexen.

Another advantage, he said, is better cooling, which allows processors enhanced control over the temperature-sensitive reaction between the rubber and the silica-silane coupling agent systems.

“For a company, such as Bridgestone, which uses silica in all its tires, it would make sense for them to change to intermeshing,” said Umemura. “They are used to using the Banbury, for which Kobelco is the king in Asia. But since Kobelco is not so [specialised in] intermeshing, it is a very good business chance for us.”

The company is now selling its mixer to tire customers and has "many references" for machines now in [operation], said Umemura, who commented: “We are getting good feedback from these customers. Hopefully we can sell more in Asia and [eventually] in Europe.”

The company has started out by making 20-30 of these mixers a year, which Umemura reckons is about 10-20 times less that the output of the market leader. It also operates a testing facility at its base in Hiroshima which houses a down-sized version of the mixer.

Potential customers, explained Umemura, "send materials for testing but, of course, will not get the same results as with a bigger machine. However, if they get a good result with a down-sized machine they might then consider a prototype machine."

The curing press business, for example, "requires fewer spare parts and there are many copy-cats," he said. "You can sell a curing press with emails: It is more of a commodity business.

Selling a mixer is not a commodity [business]. It can affect the way of making the tire, so you have to have a good relationship with customers and this takes time.”