Oxygen detection in heat treating/annealing furnace atmosphere in manufacturing of precious and non-precious metal coins

Based in Idaho, U.S.A., Sunshine Minting Inc. (SMI) is a leading supplier of precious metal and base metal mint products. Customers include governments, financial institutions and major corporations around the world.

Well known by industry leaders, SMI sets the standard for purity and quality in the production of silver and gold blanks, coins and medallions.

SMI have chosen the EC913 process oxygen analyser from Systech Illinois to monitor the oxygen in the heat treating / annealing furnace atmosphere. Concentrations as low as 1,000 ppm can cause oxidation of certain metals at high temperature, which can lead to cosmetic flaws, pitting or a dull surface finish, which is unacceptable as a finished product. After installing the EC913, operators no longer have to guess the oxygen concentration and waste expensive nitrogen to displace it.

The EC913 monitors any oxygen (air) intrusion and any leaks can be blocked or plugged. This controlled process limits waste and increases efficiency of the minting operation.

Sean Moffat of SMI, says, ‘The Systech Illinois O2 sensor has worked great and found 2 separate points of O2 intrusion in the Hayes furnace as well as proving to the annealing supervisors and operators that certain procedures were introducing O2 into all the furnaces. Installing the EC913 has resulted in savings of 800 cubic feet per hour of nitrogen on the Hayes alone’.