I was informed that API Std.682 states the specifications for the QUALIFICATION TEST on shaft sealing system for rotary and centrifugal pumps. Could it be applied to quarter-turn rotary valves too (e.g.: packing of triple-offset butterfly valves)? Use API 609, the industry standard for butterfly valves. The demands of a pump shaft sealing system are much higher than one for a butterfly valve shaft. From a UK perspective, we have completed the ISO and 77/312 type testing, in essence you have to be carefull with the mechanical testing, whilst we succeded in meeting the fugitive emission standard such as 1000 cycles, max 50 ppm for a gate valve the limiting factor is the cycles at or around 1000 cycles the valve top works tend to fail this is very relevent when looking at small forged steel valves as about 100 is the maximum cycles. One other point, the most crucial factor in overall performance from a emission standpoint is temp cycling

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