About the life of the Air Blow Heater, it becomes the value which completely different with directions for use.
A concrete numerical value cannot be shown and cannot guarantee it about the life. The most accurate life prediction method is measured by the pyrometer and other non-contact thermometer maximum temperature of the heating elements used in the state, to estimate the lifetime of heating element temperature from the graph below.
Moreover, the heating element temperature becomes a value higher about 300 ℃ than hot air temperature.
It is also possible to presume heating element temperature from hot air temperature at that of that.
However, since this difference in temperature changes with flows, it becomes quite inaccurate presumption.
If it is 800 ℃ in hot air temperature when it will carry out from now on, heating element temperature is about 1000 hours, seeing a life moderately at about 1100 ℃.
If it is 700 ℃ or less in hot air temperature, the heating element temperature reaches 1000 ℃ or less, and a life value will approach infinitely, and it will be said that it is not necessary to take the life into consideration.
However, this is a general talk and brings a sharply different result on condition of each.
As described above, it is greatly affected also by the method of voltage control.
It is affected also with the impurities (water, oil, metal powder) contained in vibration, a shock, and air.
Since various kinds of factors are involved, the life of the Air Blow Heater cannot be expected easily.
The probable life to the hot air temperature used is as follows.
These values differ also with the thickness of an electrically heated wire.
The diameter of an electrically heated wire of this life is about phi0.5.
In the case of a more thinner (an amperage rating value is low) Air Blow Heater, a life value becomes shorter.
However, there is resulting little in disconnection in normal consumption in fact, and it results in overheating disconnection by the control mistake at the time of use, in many cases.
About 300 ℃ of heating element temperature becomes high to hot air temperature.
Hot air temperature 850℃ → Heat element 1150 ℃ → Lifetime 300h
Hot air temperature 800℃ → Heat element 1100 ℃ → Lifetime 1000~2000h
Hot air temperature 700℃ → Heat element 1000 ℃ → Lifetime most permanent
However, the difference of hot air temperature and heating element temperature changes also with flows, and a difference also becomes large, so that a flow generally becomes large.
In order to obtain a hot air as much as possible after securing required life time, the one where this difference is smaller is desirable.
Therefore, if an air flow is set up few, it can be expected that a high temperature hot air could be obtained.
As an example in the case of being used as an object for high temperature, the actually applied voltage is stopped before and after 60% of rated voltage (electric power about of rating 1/3), and if an air flow is reduced according to it, an about 900 ℃ high temperature hot wind will also be obtained at the heating element temperature of about 1100 ℃.
Thus, the life of the Air Blow Heater is mainly determined by heating element temperature.
However, about the life of a heater, the guarantee as a maker is difficult.