No-bake moulding

Sinoterm: High mechanical strength environmental-friendly furan resin based on Hüttenes Albertus technology and enabling high resistance with low binder addition. Its application ranges from authomatic fast hardening tasks to longer useful life more sophisticated works. Low nitrogen and low sulphur resins have been developed for steel and high quality nodular iron casting, respectively.

Sinoterm NS: Alkaline phenolic resin mainly used in the steel industry. This nitrogen and sulphur-free system shows low emission levels during moulding, casting and hardening. Furthermore, it allows easy mould release, avoids recarburation problems in steel pieces and presents low heat cracking trends.

Koldex and Waselit: Inorganic no-bake system based on sodium silicate and mainly used in steel casting. For non-ferreous metals, binders incorporate additives enabling easy desanding. This system is being replaced by novel organic systems.

Pentex: Phenolic Urethane reactive system allowing high yields in short and medium series steel and aluminium castings. Low binder addition levels provide very good strengths with short curing times but quite lengthy sand bench life. Furthermore, the system shows good demoulding properties, low odour nuisance and provides good surfaces in steel casting. This sulphur and phosphorous-free system is environmentally friendly thanks to the use of new solvents.

Resins based on furfuryl alcohol (furan binders) are commonly cured with organic sulphonic acids and contain sulphur above 12%. This compound is responsible for sulphur dioxide emissions, odours and casting defects. Low sulphur systems, with total sulphur reduced nearly by half, drastically reduce SO₂ emissions, with the corresponding environmental and working conditions benefits. Furthermore, these systems enable sulphur reduction in recovered sands, which significantly benefits high quality nodule iron smelters.

Low sulphur systems operation is similar to that of conventional ones and their implementation lowers environmental impact and improves safety at work.

An additional advantage lies in the lower sulphur absorption by the metal matrix, that in nodular iron casting leads to graphite degeneration in parts close to the mould.



The figure above shows how sulphur is significantly reduced in casting rims.