Salt Bath 709 / 718 / 818
Installation and Operating Manual
North American Model
June 2019
Page
17
of
36
Programming the TAP to Achieve Molten Salt
You will program the TAP control to do 3 things: ramp-up (heat up) to your chosen molten temperature, heat to your chosen molten temperature itself and hold at
your chosen molten temperature. Let’s discuss these 3 things one at a time and in order:
Temperature Rate (Speed)
: The TAP uses a degrees-per-hour format for controlling the speed at which the heat will increase. Evenheat recommends a
heating rate of no faster than 1000°F per hour (537°C per hour).
Setpoint Temperature:
The Setpoint is the actual temperature you are attempting to achieve for the heat treating process. Heat treat salts have working
temperature ranges. The desired heat treat temperature of your material must be within the working range of your heat treat salts.
DO NOT OVERHEAT YOUR SALTS
– You must know the acceptable, safe working range temperatures of your salts. Do not program or otherwise
allow the salts to reach a temperature higher than the acceptable and safe working temperature range. Nitrite containing salts are prone to
explosion if over-heated. KNOW YOUR SALTS and operate the salt bath accordingly!
Hold Time:
Once the setpoint temperature has been achieved the salt bath is allowed to hold at that temperature for a period of time. It’s during this hold
time that you will perform your heat treating process. The amount of hold time depends upon the amount of time you expect your heat treat session to
last. Keep in mind that you can always abort the heat treat process via the TAP control at any time.
Using the above information, program your TAP control to ramp-up at no faster than 1000°F/hr. to reach your heat treat temperature and hold for a period of time.
Given that you are heating your salts for the first time use a hold time of 6 hours. You shouldn’t need this amount of time to complete the process and you can abort
the process when you are complete.
Start the heating process per instructions found in the TAP control users manual.
Chamber Thermocouple Controls Heat-up
You will note that the TAP control indicates “Chamber” when the process is started, as will always be the case. This means that the TAP control is working from the
Chamber Thermocouple for its control information. The reason is that chamber heat is a reliable measure of temperature at start-up when the salts are in a solid
form. Sensing the direct temperature of the solid salt does not/would not accurately reflect the heat being exposed to the salt pot and could lead to a heating rate
that is too fast.
Generally, you will allow the TAP to use the Chamber thermocouple to control up the molten, setpoint temperature.
You’ll note in the Kiln Temp row that “Cha…” is displayed. This
indicates that the Chamber thermocouple is being used for control.
After about 10 minutes of screen inactivity a large text
screen appears and “Chamber” is prominently displayed.
