Case-hardened bearings gave Kanthal significant benefits

Kanthal had major problems with roller bearings in rolling mills that caused costly production shutdowns. Together with Nomo, Timken and Avans Maskintillbehör AB, a special solution was developed. Kanthal has not had a bearing breakdown since the change to Case-hardened roller bearings, says the head of the mechanical workshop at Kanthal in Hallstahammar.

Kanthal is a world-leading brand for Sandvik's products and services in industrial thermal engineering and resistance materials, well known for very high product quality. Their special alloys and some of the products they make are the only ones in the world. Most of the products produced in the Hallstahammar streelworks are exported in wire form. It's about very thin rolled threads used in a variety of applications and products worldwide, which means Kanthal has a very wide customer group. Key applications are demanding industries in different segments, including energy and power generation, electronics, petrochemicals, medical technology, automotive and aerospace industries.

Deferred production environment

Kanthal is a customer of Nomo's dealer Avans Maskintillbehör for many years. A visit to the factory in Hallstahammar a few years ago showed damage to roller bearings used in the rollers. A demanding environment causes bearings to be exposed to severe strains. The bearings, measuring about one meter in diameter, were irreversible at regular intervals and resulted in costly production stops for changing bearings. "When Avans saw the damage to the bearings, they soon realized that case-hardened roller bearings would work better. A saturated layer is more durable than conventional layers.

Big commitment

Together with Kanthal, technicians from Nomo and the team from Avans began to seek reasons for the bearing problems. They investigated what were available for market solutions and what could be improved. The head of the mechanical workshop at Kanthal in Hallstahammar is very pleased with the commitment that everyone showed to find a solution. A development work that lasted of and on under a few years. He says, "Many have put a lot of time and thought about how we would solve the problem. We started discussing ideas with Avans and then we met with Nomo's application engineers who really worked hard to find a solution. Nomo has also done follow-ups and everything has worked very well. Even Timken's application engineers visited us and participated in the development work."

Biggest win

The solution was to use case-hardened special bearings from Timken in the application. Case-hardened bearings are slightly more expensive than conventional bearings, but in return they have longer life. The biggest profit is that we can keep our productivity by avoiding major breakdowns and costly production stoppages. Because it's a lot of money, you want to be sure it will work when you switch to a new solution. Here, all parties believed that it would lead to improvements and give something back. The head of the mechanical workshop at Kanthal in Hallstahammar received a clear sign from management when presenting the solution, which would lead to longer lifespan on roller bearings in rollers and fewer production stops. This shows that Kanthal wants to develop and dare to make investments in order to make everything to work optimally in production.

New security system

Since spring 2016 Kanthal uses exclusively case-hardened roller bearings from Timken with very good results. "We have not had any bearing damage since we switched to the new ones and are now analyzing rollers and bearings every three months. We have three complete sets of bearings, which means a total of 12. One set is in operation, one that we process and one ready set in reserve for short-term replacement." Kanthal has also installed a condition monitoring system for bearings and housing units, which means that planned maintenance stops can be done and bearings can be replaced on time by looking at trends in wear and tear.

Ready higher load

The explanation that Kanthal had for the bearing problems in its rollers is that new products and harder alloys together with increased volumes increased the strain on houses and bearings. Kanthals plant in Hallstahammar were put into operation during the 1950s. Initially, reinforcing iron and flat iron were rolled. Eventually, the development has led to new products and harder alloys, which places higher demands on production equipment. There are creative weights that hit the rollers. With case-hardened roller bearings there are now more margins, because they tolerate higher load and stroke better. It is important to accompany the machine park to meet the future.