New surface treatment procedure for seals eliminates sticking effects

RFN Effects Optimize Modern Solenoid Valves

Huge progress has been made in permanently reducing the sticking effects in solenoid valves using nanoscale materials - and the results are fascinating. Thanks to RFN™ (Reduced Friction by Nanotechnology), Simrit is able to modify elastomer materials in a way that not only drastically reduces the coefficient of friction and, consequently, sticking effects, but also keeps it virtually constant over the entire service life of the component.

The vast majority of armatures in modern solenoid valves are elastomer composite parts. This explains why the reliability and serviceability of such solenoid armatures depend on both deformability and adhesion minimization, which reliably prevents an elastomer from sticking to the valve seat. In many applications, reducing adhesion is a basic prerequisite for the functionality of the entire valve.

The contact area (i.e. the component’s geometry, roughness and topology), contact pressure force, mechanical and technological material properties such as hardness, modulus, and damping, the chemistry of the surface, and the lubricating media all have a direct influence on the size of the sticking effect. RFN minimizes these sticking effects.

In addition to these primary functional improvements, this innovative new technology for reducing a material’s tendency to stick has other advantages:

• the reduction in adhesion prevents the so-called “Monday morning effect”
• even switching times are possible
• lower magnetic forces save on installation space and allow for miniaturization
• an increase in the service life of the solenoid valve
• an improvement in chemical resistance
• a reduction in permeation as a result of the barrier effect
• no additional coatings (e.g. on the seal seat) are necessary
• RFN is FDA-compatible

Moreover, the performance of RFN solenoid armatures does not diminish even after well over 700 million switching cycles. There is no negative effect on the sealing characteristics of the elastomer; elastic properties are maintained. Nor does RFN have any negative effect on the evenness and the roughness of the sealing surface.