Technology
Tools for wax injection
All tools for wax injection are designed in-house and fabricated in the tool-making department of the Company. The design of components and the runner system is based on the experience of our metallurgists and technologist and aided by sophisticated CAD/CAM/CEA tools.
Technology
Wax patterns and components
Wax patterns and components of the runner system are injected on a wax injection machine using tools developed and produced in house. Patterns and runner systems are manually assembled in a wax tree by gluing and welding of wax.
Technology
The shelling process
Once the wax trees are finished begins the shelling process, where several ceramic layers are applied in order to form a ceramic shell. In case of titanium, which is a reactive alloy the chemical composition of the ceramic material has to be appropriate in order to prevent a reaction during the casting. In between each layer the growing ceramic shell has to be dried in a controlled environment by means of temperature and humidity.
Technology
Ceramics preparation
When the shell is properly dry the wax is extracted and the ceramic is fired in order to obtain the appropriate properties to withstand the casting of titanium.
Technology
Titanium preparation
Scrap titanium is separated based on quality and chemical structure.
The next step involves the use of two shredders, which shred scrap titanium into appropriate size pieces for making briquettes. Titanium pieces are then cleaned to remove grease and dirt. After cleaning, the material is compacted into briquettes.
Technology
Vacuum casting
Before the casting the shell is additionally prepared and placed in a vacuum chamber of the melting unit. Because titanium is a reactive alloy (high affinity for other elements at elevated temperatures, especially in liquid state) it has to be cast in a vacuum. The ceramic shell is placed on a spinning table that rotates at high rpm, which enables us to cast thin wall parts and reduce the alpha case layer; consequently, pre-heating of the ceramic shell can be minimized or even completely avoided when compared to normal gravity casting.
Technology
Finishing and inspection
After the casting process is finished, the ceramic shell is knocked out and casted parts are cut off from the runner system. In accordance with the intended use of a particular part it can be sandblasted as well as polished in a vibratory polishing machine in order to obtain the desired surface finishing.
Casted parts are inspected using X-ray radioscopy and controlled by other non-destructive methods (dimensional measurement, surface roughness, visual inspection, liquid penetrant test, etc.) and destructive methods (chemical analyses, gas analyses, tensile test, hardness measurements, etc.).
Technology
Dimensional inspection
All this enables us to provide high quality casted parts in titanium for our exhaust systems or for other customers as well.
