The final quality of a cast iron casting depends on various parameters identified when defining the process, and the ability to keep them constant. It is therefore essential that these parameters be continuously monitored using the most appropriate methods from time to time. The following can be mentioned:

Checks on the binder and moisture content in the mould production stage

The consistency and stability of the moulds highly depends on the appropriate quantities of sand and binders. Moreover, too much moisture (if the water + bentonite system is used) or too many organic binders may trigger, in contact with the liquid cast iron, the development of vapours or gases which, incorporated into the cast iron itself, lead to surface defects called “blowholes”.

Dimensional checks of moulds

Dimensional checks of the moulds are essential in order to obtain castings with the expected geometric characteristics according to the design and to limit mechanical machining, where envisaged, to remove machining allowances.

Checks of casting temperatures

These checks are needed to ensure the best possible balance of fluidity (associated with high temperatures) and reduced energy costs (requiring casting temperatures to be as low as possible).

Checks on the flow rate of the liquid cast iron during casting

These checks are important in ensuring the consistency and repeatability of cast iron pouring into the mould.

Checks of cast iron composition

The relatively rapid determination of the composition of the cast iron in the melting and holding furnaces, and of the cooling curves. These checks are essential in ensuring the desired microstructures, and therefore the desired mechanical and technological characteristics of the casting, are obtained. All of these measurements should be integrated with process simulation and optimisation codes in order to be able to predict the microstructural, mechanical and qualitative characteristics of the castings in real time.

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