Chromalox Provides Freeze Protection for DEF on EPA Compliant Mobile Heavy Construction Machinery

chromalox silicone tank heaters

The Challenge
The customer required three different versions of silicone laminate heaters to maintain the temperature above 5º C and to prevent freezing of diesel engine fluid (DEF) throughout various parts of an on-board selective catalytic reduction (SCR) system  used  for scrubbing exhaust of diesel engines on  mobile heavy machinery. These parts included a holding tank, pump and filter. Since these SCR systems are to be installed on-board large machinery, a great deal of movement and vibration is to be expected. Under these conditions, it is critical that the heaters remain in their proper positions on the pump. Therefore, the heaters needed to pass an extensive list of testing including thermal cycle, thermal shock, endurance, over voltage and exposure testing. In addition, two of the silicone laminate heaters had to be wrapped around the filter and pump. 

The Solution
From the beginning design phase, Chromalox engineers and the customer design team worked together to provide a practical, yet, simple solution that produced quality samples in a timely fashion.  The Chromalox team provided several iterations of samples to ensure the solutions were tailored to fit with the overall products and types of heavy machinery. Throughout the sample process, multiple design iterations were developed to ensure the customer was confident the pump and filter heater would remain in their respective positions.  Ultimately, an ingenious design that included Velcro® straps and rings to pull the heater tight around the circumference of the filter and pump were accepted. This final round of samples was submitted for the intense testing procedures. The final samples passed the first time through the testing processes and were unanimously approved. The final three silicone laminate heaters are: SLVI-8.41-2-0-6TP-24V-40W, SLI-14-2.75-0-6T-24V-40W, and SLAE-8.3-24.94-175P-1.67CGM-120V-250W.

The Benefits       

·   As with all customers, this customer was invited to, and visited, a Chromalox facility, specifically the facility in    
    LaVergne, TN 
·   Reduced costs
· Solution passed rigorous testing on first pass