Open Air Thermostats are classified as our A series units and they are as versitile as our B closed body conduction type thermostats. The only difference between the conduction type and the open air type is the way they sense thermal energy. Open air thermostats sense temperature through convection rather than conduction.
Snap Disc Thermostats are classified as our A series; spanning from through Water freezes at 32 degrees Fahrenheit 0 degrees C. If you were to stick a thermometer in a cup of water and put the cup in the freezer, you would find that the temperature of the water falls to 32 degrees F and then hangs there until all of the water is completely frozen.
Then the temperature of the solid water falls to the temperature of the freezer. What if you could somehow supercool the water?
That is, say that you could get the water's temperature to 10 degrees below the freezing point without it crystallizing into a solid -- you can sometimes do this using a very clean glass and distilled water so there are no points for the water to begin crystallizing. In this condition, if you tap the glass the temperature of the water will jump up to 32 degrees F 0 degrees C , and the water will solidify quickly.
A heat pack like the one you are describing contains sodium acetate and water. It turns out that sodium acetate is very good at supercooling.
It "freezes" at degrees F 54 degrees C , but it is happy to exist as a liquid at a much lower temperature and is extremely stable. Clicking the disk, however, has the ability to force a few molecules to flip to the solid state, and the rest of the liquid then rushes to solidify as well.
The temperature of the solidifying liquid jumps up to degrees F in the process. When you boil the solid, you melt it back to the liquid state. You have to completely melt every crystal, by the way, or the liquid will quickly re-solidify. You can repeat this cycle forever, theoretically, just as you can freeze and melt water as many times as you like. Our heat packs are fully reusable again and again and are ideal for any application where safe, convenient, fast, scent free, heat is required.
No batteries or electrical cords are required for use. These heat packs can produce therapeutic heat from 30 minutes to two hours or more, depending on heat pack size and application. Heat times are extended by using any form of insulation. After use, the spent heat pack can be recharged by simply placing it in hot water. Another popular model, the SH is great for wrist and elbow pain. It's designed to wrap around to ease relieve pain from tendonitis or tennis elbow.
It's is the perfect size for taming menstrual cramps. It also works great on calves, ankles and cold feet. Great for travel, car and emergency kits.
0コメント