Flexible heat conductors for efficient thermal transfer in conduction cooling

July 23, 2015 // By Graham Prophet
Pentair’s Flexible Heat Conductors (FHCs) help ensure effective thermal transfer for conduction cooling and are particularly well-suited for small single-board systems and larger systems that cannot be air-cooled with active fans for or perforated ventilation designs.

Pentair’s FHCs also provide the necessary heat dissipation for embedded systems, which must be completely enclosed due to Ingress Protection requirements.

Conventionally, the heat from a processor is transferred to the case through heat sinks, attached to heat pads with thermal paste. This results in poor heat conductivity values from the pad or thermal paste material and limited height tolerances for processors. FHCs are made from a flexible aluminum design, with superior heat conductivity properties and spring-loaded variable height adjustment. The Flexible Heat Conductor ensures processors will remain in constant contact: height tolerances no longer play a role. The FHC consists of two interlocking sections – one which is in contact with the heat-emitting component (e.g., the processor) and the other is adjusted vertically in relation to the first section. The FHC has two sections that are spring loaded and maintain consistent contact to the top of the chassis, against the inside of the case top cover. The dissipated heat is reliably transferred away from the source and into the environment through the case surface by means of heat conduction. Additional benefits include better processor performance and higher clock speeds due to effective, direct heat dissipation.

FHCs are available as off-the-shelf products in two sizes in the Schroff portfolio: 25 x 25 x 20 ±2 mm and 50 x 50 x 69 ±2 mm(L x W x H). The smaller FHC design dissipates around 15W of heat, while the larger model can dissipate approximately 50W. Larger sizes and heights are available upon request. The heat conductors are either attached to the processors by means of the existing assembly configurations on the PCB or, in the case of smaller processors, the heat conductors are attached to the processor using thin, heat-conducting, double-sided adhesive tape.

These heat conductors have already been integrated into the Schroff Interscale range of cases from Pentair as a standard cooling solution. These cases for non-standardised PCBs include