In case of pure nitriding, the nitriding characteristic number can be calculated from the degree of dissolution of ammonia i.e. quantity of hydrogen in a furnace.
Determination of H2 in furnace atmosphere is resulting from the H2 probe. MCon Nitro is using the signal of this probe, calculating the nitriding characteristic number Kn and compares it with set value. In case of variation an adequate signal is sent to the mass-flow controller for ammonia to increase or decrease the ammonia flow. The flow is being tuned until the calculated Kn value is matching the setup Kn value.
Current data regarding the flow is provided by the mass-flow controllers giving current signals 4...20 mA. Due to free input scaling MCon Nitro is capable to operate using various flow meters. Calculated results are interpreted as current signal 4...20 mA and choosing a free scale is also feasible. NH3 flow can be controlled by two mass flow controllers of different size. In order to provide such capability MCon Nitro is disposing separate parameters for controller adjustment. Regulation of process is also possible without mass-flow controllers.