Casting Without Coatings – Vision or Reality?
The demands on the foundry industry become more exacting every day. Globalization not only opens up new markets and opportunities, but it also creates an enormous squeeze on costs. Only those who succeed in enhancing productivity can withstand this growing cost pressure, however, only if they do not neglect aspects such as emission control and responsible care. Foundries have increasingly become the focus of public attention as a result of growing environmental awareness and the more stringent interpretation of environmental regulations.
Dr. rer nat. Jens Mller, Hans-Jrgen Werner, Gnter Weicker, Ashland-Sdchemie-Kernfest GmbH, Hilden/Germany Presented at the German Foundry Conference (Deutscher Gieereitag) 2006, which took place in Bremen from 3 - 4 April 2006. www.ashland-suedchemie.de
* If not stated otherwise the percentages refer to mass fractions
In spite of all limitations, the casting quality must not suffer, as it is the key to the success of the foundry industry. There is much need for action - constructive ideas are required to be able to realize the above mentioned goals. An optimal value chain is one of the key preconditions. The use of plant technology and production materials must be optimized. Here collaboration between suppliers and foundrymen plays an important (if not the central) role in establishing innovative and more advanced systems on the market.
Casting without coatings Pros and cons
The cold box process might offer the possibility of producing castings without use of coatings. On the one hand, this would increase productivity and, on the other hand, it would guarantee a very high casting quality. But what exactly does casting without coatings mean and which advantages - and disadvantages - does it provide?
Casting without coatings primarily means the use of a system of additives and suitable binders intended to improve the surface of a casting such that the coating process can be dispensed with.
In the following we will discuss the question as to under which circumstances and in which areas of iron casting it seems feasible to dispense with coatings.
Advantages of casting without coatings. Casting without coatings provides the possibility of saving material costs, both in terms of input material and in terms of peripheral equipment (drying oven equipment, coating bath, etc.).