| Temperature control is an essential quality factor in metal fabrication. Many processing steps apply heat to the workpiece. This can affect dimensions and material structure. Cooling time is required to exclude the possibility of overheating. The cooling window can be reduced if carbon dioxide (CO2) snow or liquid nitrogen are used as cooling agents.
Liquid nitrogen
It takes 0.5 - 1 liter of liquid nitrogen per kilo of metal to reduce the temperature from
+20°C to –196°C (ΔT = 216 degrees). Liquid nitrogen must be handled like boiling water because of the risk of cryogenic burns.
CO2 ice/snow (dry ice)
It takes about 0.2 kilos of dry ice per kilo of metal to reduce the temperature by 98°C. Dry ice can be sprayed or applied as pellets.
LINSPRAY® – CO2 cooling
The LINSPRAY® CO2 cooling system was developed for use in conjunction with thermal spraying but it is also ideal for temperature control during grinding, welding and machining.
Air or CO2 are generally used as cooling agents for thermal spraying. In certain cases, liquid nitrogen is also suitable.
CO2 is the most effective dry cooling agent. CO2 snow is also a highly effective cleaning agent. Special CO2 nozzles have been developed to enable uniform, directed and continuous cooling results.
LINSPRAY® components
LINSPRAY® systems consist of a CO2 high-pressure tank (or cylinder bundles with dip tubes), withdrawal valves, safety valves, a pressure gauge, a high-pressure hose and a solenoid valve with a fine filter, an expansion nozzle, nozzle holders and a control panel.
Various nozzle sizes are available to suit individual application needs. These nozzles are designed to intensify or reduce the cooling effect. The range of CO2 consumption varies from 220g/min to 730g/min with standard nozzles. |
