Watt density w p x d x hl.
Cartridge heater watt calculation.
Calculate watt density and fit after the wattage for each heater has been established the watt density and fit must be calculated.
Heat calculations watt density for cartridge heaters other heater applications.
How to calculate required wattage.
Heaters should always be sized for a higher value than the calculated figure.
For example a 1 2 x 12 cir heater rated 1000 watts has a watt density of 55 w in2.
The first thing to know is how many pounds of air need to be heated.
The size of the safety factor is dependent on the accuracy of the wattage calculation.
Kw w x c x t w weight of material in lbs.
Cartridge heaters electric insertion heaters immersion heaters square metric imperial cartridge heaters technology for industry toll free.
Watt density w π x d x hl.
Then use graph g 235 to be sure that the watt density is within allowable limits.
For calcualation purposes stock cartridge heaters have a 1 4 unheated length at each end.
Thus for a 1 2 x 12 heater rated 1000 watts the watt density calculation would be as follows.
For calculation purposes cir stock cartridge heaters have 1 4 unheated length at each end.
In order to determine whether a particular heater will perform well in your application you must compare its wattage with your requirements.
It is the number of watts per square inch of heated surface area.
You can use the following formula to determine your required wattage.
20 additional wattage is more common.
Kw wt x cp x δ t 3412 x h where.
Suppose you wanted to calculate the radiation loss.
L radiation radiation loss w in 2 x area x emissivity x 1 hr for example assume the tin block has a radiation loss of 1 1 w in 2 and an emissivity of 0 04.
Kw your kilowatt requirement.
Thus for a 1 2 x 12 heater rated 1 000 watts the watt density calculation would be as follows.
Standard air is 70 degf 14 psi scfm stands for standard cubic feet per minute and delta t exit temperature minus inlet temperature in degrees fahrenheit.
Follow the formula in this video given by chet omega engineer to understand exactly the type of surfac.
Kw scfm x delta t 3000 x 1 2 this formula can be used for standard air.
So the formula for calculating heat loss due to radiation is.
