Model 26 Torch & General Torch Questions...

[DaveO]

A question about this video: at time index 2:15 the presenter picks up the wp18 torch to explain the layout of water cooled torches. The long lead is for water in; the second longest lead is for the gas attachment; the short lead is the power connection. Then at 2:26 he says "To prevent preheating of water into the torch head, the water should always exit the power cable." That doesn't make intuitive sense to me, but I can be convinced: what am I missing in that statement?

[performance]

A question about this video: at time index 2:15 the presenter picks up the wp18 torch to explain the layout of water cooled torches. The long lead is for water in; the second longest lead is for the gas attachment; the short lead is the power connection. Then at 2:26 he says "To prevent preheating of water into the torch head, the water should always exit the power cable." That doesn't make intuitive sense to me, but I can be convinced: what am I missing in that statement?

Yes, that is correct. 1. The hose is larger, and designed for fast "dumping" of the water, as all return lines in a hydraulic system are. 2. The primary goal of the water is to keep the torch head and handle itself cool, not the cable, though it does. This is an operator comfort issue, along with a longevity issue for the torch materials 3. The cable doesn't need to be kept as cool even though water flows over it, as long as it doesn't heat up to a melting point, and under the boiling point, which it does.

[performance]

As promised, here is a link to the video we loaded online. http://www.youtube.com/watch?v=WrDg5hRXY6c

[Ray C]

Total newby here but the way I interpret it is: the conducting cable warms up and if the feed water is routed next to the conducting cable, the feed water will get warmed-up before it even cools the torch off. On the downside though, running hot water next to a conducting cable will increase the cable resistance... Double edged sword but someone probably calculated the temperature rise vs. conductivity impact and deemed it was a good trade-off...

Yes, that is correct. 1. The hose is larger, and designed for fast "dumping" of the water, as all return lines in a hydraulic system are. 2. The primary goal of the water is to keep the torch head and handle itself cool, not the cable, though it does. This is an operator comfort issue, along with a longevity issue for the torch materials 3. The cable doesn't need to be kept as cool even though water flows over it, as long as it doesn't heat up to a melting point, and under the boiling point, which it does.