Experience shows that it is frequently necessary to develop special breaker cores tailored to customers individual needs. The geometry of the breaker core can then be matched precisely to the contours of the casting concerned.
The production of such customised breaker cores often results in vast cost savings in the working and machining process which exceed the additional costs of the breaker core many times over.
With respect to performance and competitiveness, foundries and their supplier industries cannot turn their backs on the global trend to use resources more efficiently and to optimize raw materials and auxiliary resources. Great potentials can be found in the field of energy efficiency in the context of energy intensity of production processes in foundries. In addition to melting, additional energy is needed and accordingly supplied at various points in the production process. The riser system is one of the main points in the process where extra energy is added. Nowadays, solidification control is achieved primarily with exothermic feeder sleeves that are used for point heating of the feeder metal, thus enabling feeding relevant nodes of the cast part. Here, the exothermic reaction of the feeder material adds extra energy to the process while additional liquid metal is kept ready in the riser system for feeding. The basic design principle of the ECO riser is a combination of exothermic inner riser, which holds the liquid iron for feeding, and an insulating cover that reduces heat transfer to the environment of the riser and thus greatly increases energy efficiency. The supply of additional energy thus can be reduced and at the same time the efficiency of the product can be increased. This riser system was consistently further developed in the last four years in collaboration with Georg Fischer, Leipzig, and different ECO risers with a module range from 1.9 cm to 4.5 cm are now available as series products.
POINT risers® are thick-walled risers which enable feed metal utilisation of up to 60-70%. They have been developed especially for demanding applications in modern high-pressure moulding lines. The properties of the solid riser wall range from highly exothermic to highly insulating, according to the intended application. The optimised material properties and the adapted volume enable substantial improvements in output and economic efficiency.
The self-centering inner contour ensures fast charging of the pattern plate with risers in sync with the moulding plant. The small neck of the riser only requires the area of the metal connection channel between casting and riser. In contrast to risers with a breaker core, this enables absolutely accurate positioning of the riser. These risers can thus be used on the smallest items, such as cams or fins.
During pouring of the moulding sand into the moulding box, the POINT risers® are initially held up by a pin. As the moulding sand is compacted, the riser is moved in the direction of the pattern, thus compacting the moulding sand between riser and pattern. The casting contour under the riser is produced by the moulding sand which is moulded between riser and casting in the form of a breaker core. The neatly formed casting contour is only interrupted by the small metal riser neck.
THERMO-risers are thick-walled risers which enable feed metal utilisation of up to 60-70%. The properties of the solid riser wall range from highly exothermic to highly insulating, according to the intended application. The optimised material properties and the adapted volume enable substantial improvements in output and economic efficiency. A modulus range between 0.8 cm and around 8 cm can be covered with risers from this product segment.
In order to cover this broad modulus range, our formulations are tailored to the different geometries concerned. This enables modulus-specific factors such as firing temperature, ignition, burn-off and heating time to be optimised. The particularly robust design of the THERMO-risers means that they are equally suitable for use in hand moulding shops or in automatic high-pressure moulding lines. Fixed pins or spring-loaded pins can be used, according to the underlying conditions and the application concerned.
The sintering tendency of the riser rests allows them to be separated from the remaining moulding sand virtually in their entirety in the course of the shake-out process. In addition to the broad selection of different riser geometries, a choice of different qualities is also available.
Area of application:
The classic fields of application for our exothermic THERMO-risers are cast iron with flaky and spheroidal graphite and cast steel. The available ISO qualities also extend the range of applications to non-ferrous metals.
is one of Europe's leading manufacturers of exothermic and insulating risers in Europe.
We develop and manufacture our products for the European foundry industry at our company headquarters in Grevenbroich (between Cologne and Düsseldorf). Ever since the company was founded in 1988, we have rigorously pursued the ongoing development of our innovative product portfolio and our production engineering in order to offer our customers the broadest possible spectrum of solutions geared to the industry's practical needs. Our portfolio comprises several hundred types of risers covering a broad scope of modulus and applications. GTP Schäfer deploys a 3-shift production system, manufacturing its high-quality riser systems with a workforce of around 80. Our customers include iron and steel foundries with automatic moulding machines or hand moulding shops.