Clarke Valve receives API 641 for Shutter Valve design

14 May 2018

Clarke Valve has received API 641 certification of its proprietary Shutter Valve design, the first control valve to achieve this certification of low fugitive-emission performance.

The API 641 standard applies to all stem seal materials and requires a stringent maximum allowable leakage of 100 parts per million by volume (PPMv). This API test standard calls for 610 cycles of the valve under extreme temperature fluctuations to evaluate emissions performance over an accelerated life cycle.

Fugitive emissions from legacy valve designs in industrial facilities are a major contributor to air
pollution and global warming. Kyle Daniels, President & CEO said, “Most people are unaware
that 80% of refinery methane emissions come from traditional valve stems. Since the Shutter
Valve’s unique design provides a superior seal at the valve stem, it drastically reduces these

The patented Shutter Valve, by Clarke Valve, was independently tested by Yarmouth Research
and Technology, LLC, who certified the valve passed testing with less than 20 PPMv of leakage,
well below the 100 PPMv limit. The Shutter Valve’s distinct design, already the best performing control valve in the world, is now also the most environmentally friendly control valve ever certified.

Image courtesy of Clarke Valve