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Qualities

The riser additives employed today are produced from insulating and/or exothermic materials.


The exothermic materials are based on Goldschmidt’s process, which is also referred to as the aluminothermic process. The aluminothermic reaction between aluminium and oxygen, which originates in part from the added iron oxide, releases a large quantity of heat.



Fluorine compounds in small quantities serve as a catalyst for this reaction. In order to prevent the powders from slagging as a result of the high temperatures, the reaction has to be moderated. This is achieved by diluting the exothermic components with various fillers.

Heating, welding and anti-piping powders are based on this aluminothermic reaction, in the course of which very high temperatures are generated.

THERMEX

Our standard material THERMEX is a highly exothermic, quickly igniting riser material of extremely high stability. After the reaction, the riser body possesses a high pore volume and good insulating properties. The characteristic EXO values such as ignition and burning time are adapted to the modulus of the risers.
The THERMEX qualities have been developed especially for use on modern high-pressure moulding lines and thus possess a high level of mechanical stability.


THERMEX „FA“

THERMEX “FA” was developed to help our customers reduce the fluorine content in the sand system. This material offers an exothermic capacity comparable to THERMEX and identical properties, but with a reduced level of fluorine content.

THERMEX „FF“

This is a highly stable fluorine-free riser material. Its properties are roughly comparable to those of THERMEX. Fluorine is substituted in this riser material.

THERMEX „CB“

THERMEX “CB” is a low-fluorine and exothermic/insulating riser material of good stability and reduced weight. Due to the high level of high-quality insulating materials contained in this agent, the riser body possesses a high pore volume and excellent insulating properties after the reaction. The characteristic EXO values are adapted to the modulus accordingly.

 

THERMISO

THERMISO is an insulating riser material which, in addition to its main area of application at non-ferrous foundries, has also been developed for special steel casting applications. The high proportion of high-quality insulating materials enables the riser modulus to be extended.