Heating a Nichrome wire around a glass tube

[swallace36]

Hello,

Stupid computer scientist student speaking here.

I am looking to heat a few inch long glass tube with a OD of around 10mm and wall around 1.5mm wrapped in Nichrome wire to around 365F. Air will then be drawn through the tube to heat up herbs sitting about the glass tube. (vaporizer) I want to use a battery to heat the wire. I will probably put another glass tube around the inside one to keep with wire from being exposed.

Does this sound plausible? I am in the very rough stages of research but NEED to find out if I am headed in the right direction...

 

[stedwards]

A hot nichrome wire can be used to cut glass through heat induced expansion stress. See you tube. There are few videos. So you don't want that.

You might want to use pyrex glass or insulate the wire from localized heating. You can can also buy lengths of heating wire taking various standard voltages.

 

[jerromyjon]

I would think cutting the glass wouldn't be a concern between 355-385F and I imagine you wouldn't want to exceed 400F but you would presumably need to adjust the temperature for calibration, and perhaps for preference... so you need to figure out how much energy you need to bring the length of wire to 400F and add a suitably rated potentiometer.

 

[stedwards]

A concern would be cracking from localized heating where the NiCr alloy contacts the glass.