MDC’s Variable Leak Valves are engineered for fine and precision gas control into high and ultrahigh vacuum environments. Offered in two series, the MLV (Fine Leak Valves) and ULV (Precision Leak Valves), each is manually actuated and designed to regulate the admission of hot, corrosive, or reactive gases with exceptional sealing performance.

Fine Leak Valves (MLV Series) feature adjustable leak rates down to 7.5×10⁻⁸ Torr l/sec (9.99×10⁻⁷ Pa·l/s), utilizing a stellite superalloy seat and a replaceable nickel diaphragm. Constructed from 304 stainless steel, these valves operate reliably under temperatures up to 450°C (842°F).

Precision Leak Valves (ULV Series) deliver even finer control with leak rates adjustable to 1×10⁻¹⁰ Torr l/sec (1.33×10⁻⁹ Pa·l/s). A sapphire poppet and OFE copper seat ensure long-lasting precision. A cantilever-style manual actuator with ultra-fine threads offers unparalleled leak rate adjustment capability.

Industry Applications

MDC’s Variable Leak Valves are essential for controlled gas admission in UHV chambers, research labs, plasma physics, surface science, and thin-film deposition systems. With support for high temperature bakeout and chemical compatibility, they are ideal for precise pressure regulation, calibrated gas leaks, and residual gas analysis. These valves support reliable performance in aerospace, semiconductor, and materials science applications where leak-free, fine control is critical.