Selecting A Heater For Your Molding Application

December 10, 2018

It’s imperative to select the right heater for a molding application if the operation is to be a success. For use in molding applications, strip heaters, cartridge, and tubular are the most common heating elements.

Selecting the right heater for a molding application entails considering both the physical requirements and heating requirements at hand. In considering heat requirements, know what temperature needs to be reached; how quickly that temperature is achieved; and potential heat loss sources through conduction, convection, and radiation. In considering physical requirements, know the physical space the heater must fit, any insulation adjustments in the fit, and any additional space needed for junction boxes and lead terminations.

Installing A Heater:

After selecting the heater, lead terminations, condensation, ground connections, temperature control, insulation, and accessibility must be considered. Address each factor before initiating the heater installation process.

Thermocouples And Temperature Control Factor:

Consistent part production is ensured by proper temperature control. Consider essential characteristics and features in selecting the ideal temperature controller. Processing conditions can be checked via a range of diagnostic functions that exist in most modernized design controls. These diagnostic functions include the location of thermocouples, optimization of amperage to the norm of 15-30 amps, and evaluation of control zones. Achieving basic control of the mold temperature could be as easy as attaching thermocouples to an exposed surface after inserting it into the mold. Built-in thermocouples are features in certain types of heaters. Internally positioned thermocouples in cartridge heaters have several potential positions along the length of the heater. Most types of cartridge heater thermocouples and positions are either along the heaters length and grounded to the sheath, bottom grounded at the end disc opposite leads, or center-positioned for relative temperature sensing.

Lead Wire Channels Factor:

Magnetic fields and heat tend to be generated when currents circulate through lead wires. Pressing those wires together isn’t advisable, which is why it’s always a good practice to oversize wire channels by 50% whenever possible. To prevent damage, it’s also good practice to split wires into different channels and cover all external wire channels. Leave enough room to not strain for junction box connections, and never force bends in lead exits. Avoid assembly peeling of insulation by rounding corners. Avoid junction box connection confusion by tagging all wires.
Please contact ESCO Heating, AC, Plumbing & Electric at (801) 204-9444 for more information on selecting and installing the right heater for your molding application.