01Separate heat-up and holding loads
For heat-up, record mass, specific heat, initial and target temperatures, and the time available. For holding, account for ambient temperature, insulation, exposed surfaces and heat drawn away by the process.
If the heater warms a filled vessel, include the contents in the assessment rather than using the vessel wall alone.
02Estimate sensible heat first
Use P = m × c × ΔT ÷ t. With mass in kg, specific heat in kJ/(kg·K) and time in seconds, the answer is in kW. For 2 kg of aluminum at a specific heat of 0.9, a 40 °C rise in ten minutes takes about 0.12 kW before losses.
That figure covers the aluminum only. Add fixture heating, losses and process heat demand separately.
03Check watt density on the active area
Divide the heater wattage by the actual heated area. Exclude holes, the lead exit and unheated margins. Shrinking the active area at the same wattage raises watt density.
Check the model’s rating for the intended mounting, adhesive and operating temperature. The same watt density may not suit a different mounting method.
04Measure both temperatures on the trial
Record the workpiece temperature and a representative temperature near the heater. The first shows whether the process reaches its target. The second helps check the heater and mounting materials.
For a quote, send a mounting photo or drawing, supply voltage, heat-up time and insulation details.