Four managing directors, two secretaries, and two locksmiths, that was the initial lineup of the industrial furnace and hardening accessories GmbH Unna. The company started in 1993 as a small locksmith's workshop with administration in the basement of a private house.

"Originally, the plan was only to offer spare parts and accessories. But after seven years, the first complete furnace was sold," reports Hendrik zur Weihen, who is now the sole managing director and shareholder. The son of co-founder Friedrich Wilhelm zur Weihen has worked in the company during his studies before joining the management in 2016. Today, IHU employs around 30 people and also exports to other European countries and overseas.

Furnaces for various applications

The shaft, hood, chamber, and continuous furnaces are individually planned and manufactured according to the customer's needs. "There are various heat treatments to achieve different properties, depending on which parts are to be treated. Accordingly, the furnaces must be different, which operate in the temperature range between 400 and 1,100 °C," explains Hendrik zur Weihen.

The best-selling type of oven is the shaft furnace for heat treatment of gearbox components. "We are constantly working on improving energy efficiency through better insulation materials, as well as on a higher performance and availability of the plants," says the managing director. Almost half of the customers are contract hardening shops and gearbox manufacturers, 20 to 30% come from sheet metal and wire production. In the remaining cases, it's about a wide variety of applications around heat treatment, such as in aerospace technology. In addition to manufacturing various new furnace systems, repairs, modifications, maintenance, and servicing as well as contract work are also carried out at the Unna site.

Added Value through Sustainability

The ovens from IHU are characterized by special ease of use and good availability of spare parts - the staff by years of experience from contact with the customer. The company's 30th anniversary is to be celebrated accordingly. The company boss is not looking into the future too relaxedly, as investment decisions are often postponed and many customers are on short-time work. Nevertheless, his goal is the further development of the company. A focus is on improving the plants in terms of sustainability. The managing director is looking forward to further "exciting challenges in a versatile environment."