Heat Pipe Recipe

 

Heat Pipe (HamPipe™)

Recipe By: Kownurko, Chu, Teperov 

Ingredients:

• 3 Copper Tubes (In this case 1/4" and 1/2" and 3/4" in diameter)
• Braided Stainless Steel Netting (enough to cover the length of the interior tube 2 or 3 times)
• Lead-Free Solder (a lot)
• 1 Blowtorch 
• 1 Copper 1/2" to 1" fitting
• 1 Copper 1/2" to 1/4" fitting
• 1 Copper 1" End Cap
• 1 Copper 1/2" End Cap
• 1 Drill
• Steel Wool
• Flux for Tinning 

(Optional Ingredients):

•  1 Pressure Gauge
• 2 Thermocouples 
• 1 Heat Gun
• 1 Vice
• 2 Small Pieces of Oak (or really any other wood)
• 1 Valve (used to evacuate heat pipe and re-fill with different heat transfer fluids) 

Prep. Time: 4 Hours
Solder Time: 30 Mins
Cooling Time: 30 Mins
Total Time: 5 Hours

Directions:
1. Begin by making sure that all of ingredients are in order, including all of the necessary safety equipment for the task ahead (gloves, eye protection, et al.).
2. Use the drill to drill between 12 and 18 holes along the top 1/6 of the 1/4" copper tube.
3. Use the steel wool to clean the inside and outside of each end of tubing, so that each portion is prepped for soldering.
4. Use flux on the outside of the 1/4" tube (leave about 2" of tube exposed above where the fitting will rest) and the inside of the 1/4" to 1/2" fitting. Solder the two together.
5. Layer braided stainless steel over the outside of the 1/4" tubing until it fits snugly within the 1/2" tube. Feed the 1/4" tube into the 1/2" tube.
6. Flux and solder the 1/2" tube and the 1/4" to 1/2" fitting to hold the two tubes together. Set aside for the next several minutes.
7. Flux and solder the 3/4" cap onto the 4" length of 3/4" tubing followed by the 3/4" to 1/2" fitting on the other side. This will make up your fluid "well" (also known as the evaporator end of the heat pipe).
8. Feed the 1/4" and 1/2" segment of the heat pipe into the fluid well, and solder the 3/4" to 1/2" fitting onto the 1/2" tube. (Don't forget to use flux on the joint first)
9. Here, either add a properly sized valve to the open 1/4" end, or fill with 25mL of whichever heat transfer fluid you chose (we recommend water for this specific heat pipe) and cap the 1/4" end.
Note:  If you choose to cap the system, make sure to heat the fluid at the bottom, and wait for some vapor to come out of the top of the heat pipe before capping the system. This will ensure that your heat pipe is properly evacuated.
10. Now you are free to test your heat pipe however you so choose! This is where you use the vice to hold the heat pipe (at an angle), the oak to isolate the system, the heat gun as a heat source, and if you chose to use the valve, you can also attach a pressure gauge to the top.