DuPont™ Kalrez® Valve Stem Packing (KVSP™), is a combination of chemically-resistant DuPont™ Kalrez® perfluoroelastomer (FFKM) parts and DuPont™ Vespel® V-rings that can reduce stem-based fugitive emissions and improve process control throughout the lifespan of the valve.

Fugitive emissions remain a concern for many industries due to their potential to create environmental harm and incur economic costs. KVSP™ has the ability to significantly reduce stem-based fugitive emissions of methane and can also be used for handling other gases including hydrogen. KVSP™ systems increase a valve’s ability to react quickly and smoothly to process changes. It reduces process control variability to the control system’s capability, resulting in improvements to both yield and product quality on specification.
Minimize fugitive emissions while increasing efficiency and cost savings
KVSP™ systems provide performance that approaches zero leakage. This is verified using EPA Method 21 for the determination of leakage of hydrocarbon-based volatile organic compounds (VOCs).
KVSP™ requires smaller valve actuators than those required for graphite packing because it requires less compressive force and has much lower valve stem friction, leading to significant cost savings.
KVSP™ reduces the frequency of costly repairs or replacements due to its lower loading (lower wear rate), extending the lifespan of the valve and without needing regular adjustment.
Benefits
Minimization of fugitive emissions over a long service life.
Lower actuator cost due to lower actuation force needed compared to graphite solutions.
Improved process control due to better alignment between the control system and valve response, thanks to low stem friction.