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3.6.4
Other possibilities
In some cases the welding machine may already have liquid cooling and it can be very straightforward to
connect the welding camera to the same cooling circuitry. This method of cooling can be applied if the
following conditions can be met:
•
The cooling liquid temperature is always sufficiently high to prevent any risk of condensation
•
The entire cooling liquid circuitry is compatible with aluminium to prevent any risk of corrosion (if
this is not the case, the usage of magnesium anode can be considered)
•
The continuous flow of cooling liquid through the camera is ensured (e.g. all cooled components
are connected in series)
The usage of tap water is not recommended since the above conditions are usually not met.
3.7 Liquid cooling with pressurized air insulation
Liquid cooling with pressurized air insulation (combined liquid and air cooling) can be applied in extreme
conditions where either method may not be sufficient separately. In this cooling method the camera and
the cables are thermally insulated from the environment and the camera end of the insulation is not fully
sealed. Liquid cooling is connected to the cooling connectors of the welding camera and pressurized air is
blown through the insulation in such a way that the air escapes the insulation from the camera end. Liquid
cooling keeps the camera cool while the flow of pressurized air inside the insulation keeps the
temperature inside the insulation cool. This prevents the overheating of the cables and also improves the
efficiency of liquid cooling.
Table 3.2 summarizes the results with combined liquid and air cooling. Cooling hose twisting and
aluminium foil wrapping were applied around the cables (Figs. 3.2 and 3.3). The cables and the camera
were inside a pyrojacket (Fig. 3.11) and the interface between camera and pyrojacket was not sealed.
Table 3.2. Results with combined liquid and air cooling.
Temperature
Pressurized air insulation
1 bar
Pressurized air insulation
2 bar
Ambient (
°C
)
290
290
Camera body top side (
°C
)
53
49
Camera body bottom side (
°C
)
43
40
Cables(
°C
)
42
37
Camera (
°C
)
39
37
Cooling liquid (
°C
)
25
25