IceJet : Clean cutting technology with ice abrasive water jet with reduced environmental footprint

Knowledge Transfer Office UL

Andrej Černetič

Tel: +386 70 746 015

E-mail: gospodarstvo@uni-lj.si

The innovation involves the development of a pioneering technology for ice abrasive water jet cutting (LAVC). Standard existing AVC cutting machines use mineral particles at room temperature as the abrasive. This mineral abrasive reaches high velocities in the form of a water jet (above 600 m/s depending on the operating pressure). The use of ice instead of abrasive is possible at very low ice particle temperatures (below -100°C), since only at these temperatures does ice have the appropriate mechanical properties needed for effective material removal.

The essence of the innovation lies in the solution for the production of ice particles and a system for their stable introduction into a high-speed water jet and acceleration towards the workpiece for cutting purposes.

1. The system enables the production of ice particles of suitable dimensions, shapes, and crystal structures appropriate for the removal of materials such as metals, polymers, and biomaterials, which cannot be efficiently processed using a pure water jet.
2. The solution allows for the management, transfer, and introduction of the created ice particles into the cutting head at a temperature of around -190°C.
3. The solution enables the creation and control of parameters in the cutting head, such as the temperature of the high-speed water jet (down to -20°C), stability of mass flow, and appropriate temperatures of the transport gas and the cutting head walls. Control is established in all segments of the solution to ensure appropriately low temperatures of the ice particles, which critically affects their material removal capability and transport properties.

The innovation is intended for use in fields such as the food industry, medicine, seal manufacturing, and the processing of hard-to-machine materials, such as titanium alloys, where abrasive water jet cutting is already used, but inclusions are undesirable.

The advantage of using ice instead of mineral abrasives is the cleanliness of the machining process while maintaining high cutting efficiency. Chilled ice particles surpass soluble abrasives reported in the literature, as ice has greater hardness and compressive strength at low temperatures. After machining, the ice particles melt, leaving the workpiece clean and free of inclusions. The temperatures at the cutting edge are lower, which is important for use in the food industry and in microtechnologies. From an environmental perspective, compared to AWJ, the amount of solid particles in wastewater is reduced by 99%.