Selection
Selection of PTFE Heating Tube and Teflon Electric Heating Tube
Select different materials according to different process requirements. For example, PTFE electric heater has excellent heat resistance (long-term use temperature from -250℃ to 260℃), strong acid corrosion resistance, and is not easy to scale (almost all viscous substances cannot adhere to its surface, so it is widely used in surface treatment industry). The intelligent temperature control system used with it can control the process temperature within about 1℃. Set automatic control of heating, heat preservation, and cooling, with high and low temperature alarm digital display intuitive and clear.
Selection Basis
1. Internal dimensions of the tank: length X height X width, liquid level height.
2. Process temperature, starting temperature, ending temperature.
3. Process required heating or cooling time (h).
Heat Exchange (Heating, Cooling)
Q＝V×C×r×β（t2-t1)/T (kcal)
V: Solution volume (liter)
C: Specific heat of solution (kcal/liter×℃)
r: Specific gravity (kg/liter)
t1: Initial temperature of solution
t2: Final temperature of solution
β: Heat loss coefficient (take 1.10-1.30)
If Q is positive, it is the heat required for heating
If Q is negative, it is the cooling capacity required for cooling
T: Heating or pre-cooling time h (hour)
Electric Heat Equivalent (Electrolytic Heat)
Q＝0.864×I×V (Kcal/h)
I: Total current A V: Tank voltage V
Determination of Heat Exchanger Area S
S＝Q/K×ΔT×t
Q: Heat exchange (kcal)
K: Heat transfer coefficient kcal/m2×hr×℃ (refer to heat transfer coefficient table V)
V: Solution volume (liter)
ΔT: Average temperature difference
t: Set heating (cooling) time (h)
Selection
Determine the heat exchanger area based on calculation, and determine the number and shape of heat exchanger groups according to the tank (reactor) size, generally "U", "W", "L" coil type. When heating, the heat exchanger is at the bottom of the container; when cooling, it is placed 100mm below the liquid level, and the product is in a "一" shape.
