This frying pan features a rather special material: small particles of ferritic chromium steel have been applied to its base by contract coating company obz innovation using a cold spraying process. Machining then provides the “final finish”. Working jointly with LMT, the coating specialists have now perfected and substantially speeded up this process.
Modern pans are characterized by non-stick coatings and perfect heat conductivity. The production of their complex high-tech surfaces is carried out by specialists, such as obz innovation in Bad Krozingen. This leading contract coating company is an acknowledged specialist in cold and thermal spraying technology. obz CEO Eberhard Schopp explains how the pans are made: “We first treat the base using a cold spraying process. The next step involves perfecting the resulting chromium steel surface.”
Turning rather than polishing – but how?
Originally the coating experts relied on a time-consuming and therefore cost-intensive polishing process. “We asked ourselves how we could optimize this slow production process,” says Schopp. A feasibility study showed that a turning process would offer huge time benefits. However, the chromium steel layer tends to adhere to the turning tool, which results in decreased tool life.
Eventually teamwork produced the perfect machining solution: obz CEO Eberhard Schopp and LMT TOOL SYSTEMS’ Marco Becker and Sven Ebinger found the right tool innovation. Their answer uses the Steeltec indexable insert with FMS geometry and PVD super nitride coating produced by LMT alliance partner Boehlerit. Its crystalline structure stops the chromium steel particles adhering to the insert. The main machining parameters, such as cutting pressure and workpiece holder, were also optimized.
The result is impressive: the time it takes to process one pan has been cut from 5 minutes to 30 seconds. Now up to 250,000 induction pans a year leave the plant in Bad Krozingen. “The turning process brings us enormous economic benefits,” acknowledges Schopp.