Regarding an oven for heat treatments, as for any thing, its cost depends on many variables.
1.temperature control regulators programmers, serve as the object .Also with the most 'economic and' can set many stops but you can not save programs, and this 'implies less reliability.' I Regulators with programming, disproportionately expensive.
Finally, the PID and 'a must if you want a good precision.
2.Actuators: You can 'have a good accuracy of 1 degree Centigrade, -1 degrees Celsius, even with a normal teleinterructors (a relay' electromechanical).
Rele'a a solid state (SSR), with a command-Off (time proportioning) gives greater reliability '.
With 50 euros you can take a SSR affordable, reliable, equipped with a sink.
3.Power: To determine the maximum power, you need to size the resistors.Calculate those Ampere and Ohm resistors should have the function of supply voltage and the maximum power you want to own the bakery.
Note that a few hundred watts them use the same electrical equipment concerned.
Type overtemperature alarms, the cycle ends, etc.. Are not required, but it would be better to provide them a "place" in the design of an electric oven.
4. Refractory strate: It is calculated according to the desired thickness and materiali.I insulating refractory bricks are usually used for thermical treatment furnaces .Per the type of application that we are concerned (knives, razors and freehand), you can ' opt for Class 23 or 26.
The former are more 'lighter,' easy to work (in case you need to do to incorporate pre-existing channels) and have a lower conductivity 'heat (greater insulating power). Their strength and' pear 'and possess a lower temperature Maximum operating less than 1260 degrees centigrade.
refractory strate insulation available are low in iron, both for use in reducing atmospheres and is normal.
Those for reducing amosfere on equal 'class, cost much more'.
5.Termocoppia: For the types of applications that concern us are happy that both the K-No. The latter are cheaper and can be used up to 1200 degrees centigrade.
The k-coated AISI 310th inconel can be used up to 1100-1150 degrees Celsius, otherwise you will opt for those to finish last ceramico.these last longer, 'than Inconel coating, but most have a temperature detection 'slow.
6.Note end: The divided voltage power (W / V) provides Amps (current density).
Example: 2000/220 = 9.1 Ampere
The Ohms are V / A.Esempio: 220 / 9.1 = 24.1.
2.5 kW are used in heating and then another few hundred for the other electrical components.