Burkert LFC Enhances Steel Heat-Treatment Process

Burkert Fluid Control Systems has revealed that the Institute for Materials Engineering (IWT) in Bremen, Germany, is using a liquid flow controller (LFC) in its heat-treatment processes. The IWT uses the nitrogen-methanol process to harden steel as an alternative to gas carburising with endogas. In this process, liquid methanol is directly introduced into a furnace, with the precise regulation of the methanol controlled by Burkert's LFC.

The advantages of this method are that dosing of the methanol is achieved with precision and is transparent; recording the reproducible consumption and flow values is carried out through the LFC and can be fully documented. In contrast to endogas, methanol is cheaper, easily stored and can be precisely fed into a furnace, depending on the process requirement. In addition, because there are no operating and investment costs for an endogas generator, the nitrogen-methanol offers a real alternative - particularly as it is more energy efficient.

In the IWT's test plant, the Burkert LFC automatically controls dosing of methanol, reacting to disturbance variables such as pressure - either as fluctuating pump pressure in the loop upstream of the LFC, or as pulsations in the pipe downstream of the LFC - and always keeps the required dosage of methanol constant through re-adjustment. The resulting high precision dosage keeps operating costs low and guarantees optimum efficiency. In comparison to flow controllers that measure according to the Coriolis principle, the LFC, using differential pressure measurement, offer advantages due to its lower cost.

In addition, because the measurement principle of the LFC requires no moving parts, such as impellers, incidence of wear in the unit is considerably reduced. Useful for the scientists at the Bremen institute is the improved knowledge of the process obtained through the recording of methanol consumption and the temporal flow characteristics. The LFC is an intelligent, integrated, cost saving solution for applications where several liquids or a liquid and a gas must be regulated simultaneously.

Due to its fast and accurate flow-rate measurement, the LFC is suitable for the dynamic control or metering of liquids such as deionised or demineralised water, methanol or low-viscosity oils. The LFC can therefore be used in a number of industrial applications, including heat treatment (by carburisation or endogas generators), testing, surface coating, cooling (machine tools), filling, packaging, and in combination with Burkert mass flow controllers, the simultaneous dosage of gases and liquids in atomising or sterilisation processes.