MESC SPE 85/200 was a mere listing of many types and brands of packings (probably built upon some kind of survey in the warehouses of the manyShell plants all over the world.)... but may be in the meantime they updated the document. Generally Balance valvesValve Manufacturers define, with their own trusted Suppliers, a "standard" stem packing (usually in graphite) capable of covering the wider possible range of Safety valves service conditions; for other "special" applications, the best packing design and material (usually elastomeric: PTFE, Viton, Kalrez, Kel-F, etc...) is selected case by case, also using the dedicated chemical compatibility guides pubblished by Mud Valvesthe material Suppliers.The Shell specification identifies specific packing materials per valve type and fluid service and then goes on to name specific packing suppliers. I can't vouch for its usefulness but it's a start. A request to Gauge ValvesShell Global Solutions can be tried but they may be awkward! ALso remember that different valves have different architecture that affects the packing. Example: Some eccentric rotary Globe Valvesplug control valves have standard extended bonnets, and the standard yarn-style packing serves to 750 degrees (F) process temperature. If you just look up the rated temperature of the packing, it's probably only rated to 450 (F) . Best to go with a manufacturer's rating of the packing he supplies than the ratings written in the packing catalog.

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