Saturday, November 14, 2020

HK 300mm Compressed Heater Chuck

HK 300mm Compressed Heater Chuck

 BACKGROUND

To reduce the overall cost for an existing application, BCE developed a 300mm aluminum heater chuck that is un-brazed utilizing the compression of two plates with countersink set screws. The heater surface specs were 0.003” flatness at a 0.005” parallelism. Using a 208-volt power supply at 9.7ohm, start @ 25°C temperature and ramped from 100°C to 465°C in 23 minutes. 

SCOPE

Aluminum Heater Chuck needed to satisfy the following:

  • Achieve temperature up to 435°C  @ +/- 2% or better 
  • Internal element must be able to withstand temperatures up to 600°C
  • Anodized surface for electrical isolation 
  • 208 Volt, 9.7 Ohm, 4,460 Watt (+5% / - 10%) 
  • Thermocouple bore hole to be placed at the center (variable) 
  • 4 point temperature profile on the top surface of the heater 
  • Used an infrared sensor for each 4 point locations
  • FINISH: Hard coat anodize per MIL-A-8625F, Type 3 Class1 Hard-coat thickness  

OUTCOME

BCE produced a highly effective high 300mm heater with exceptional uniformity better than the proposed 435°C (+/-2%).  After the initial ramp, the heater maintained 435°C (+/- 1%) as per the chart below (Temp profile #5). 

300mm heater chuck
BCE
510-274-1990