Heat pipes are passive heat transfer components based on the use of a two-phase fluid. Most of EHP heat pipes are made of aluminum extruded profiles filled with ammonia. Our products portfolio also includes other models of heat pipes with a large variation of size, diameter, fluid, material, heat flux, etc. 

Space-qualified components available off-the-shelf or customized products based on your precise needs, both are possible. EHP can design innovative solutions with full customization. 

EHP also delivers equipment for spacecraft propulsion or thermal control, like ultra-clean piping (rigid or flexible). 

With more than 40 years of heritage, EHP has manufactured many different heat pipes made of different materials (aluminum, stainless steel, copper, etc.) and working fluids (ammonia, propylene, water, etc.). 

EHP has been the sole supplier for heat pipes of the the OneWeb GEN1 megaconstellation (> 648 satellites). The OneWeb project started a new era for EHP heat pipes product line: a new dedicated production line has been built and delivers now 4.000 heat pipes per year and per shift. With the signature of additional contracts, following the end of the OneWeb deliveries, EHP became the leader of Space heat pipes.

Based on the latent heat of the working fluid, heat pipes act as highways for the heat. Completely passively, they homogenize the temperature in every point of themselves and allow to transport power. 

The working principle is the following: 
• In front of the hot source, the liquid is evaporated. 
• Then the vapor goes through the pipe to the cold source. 
• In front of the cold source, the vapor is condensed. 
• The liquid goes back to the hot source because of capillary pressure created by a groove or a mesh and the cycle continues.