Reducing drive torque in needle valves through tip material selection with a tribological approach

Abstract

High-pressure regulation, critical in applications such as cold gas thruster, often faces stiction between the needle valve tip and body, affecting precision and reliability. The interaction between different needle tip and valve body materials plays a significant role in pressure regulation. This study evaluates the performance of needle valve tips made from four distinct materials (steel, aluminum, POM-polyacetal, and Nylon-66) paired with a steel valve-body. Experimental validation reveals that the steel tip offers the highest wear resistance and torque (1.2 Nm at 100 bar), while POM and Nylon 66, benefiting from low friction properties, require lower torque (0.55 Nm and 0.65 Nm, respectively). The steel tip exhibits increased surface roughness, whereas aluminum demonstrates higher wear compared to the other materials.