Does anybody know the top working temperature of nodular cast iron GGG-40 for bodies & discs in valves ? Only 0,1 bar working pressure.Long before metal material limitates your upper temperature range, bearing and sealing materials (stem and seat) will limit what you can do.Also the fluid, in combination with sealings and inner coating,(if any or other than the sealing material) will give you a temerature limitation.The third is of course the actual valve detailed construction: what is the valve in detail actually built for.A normal max limitation for a normal, soft sealed construction, centric industrial BFL valve would probably be araound 180-200 deg C, with PTFE based sealings. There is normally a somewhat lower limit for type 'district heating', metal seated (or soft sealed) BFL valves, being normally built to demanded for temperatures below 140 deg C.Standard valves with EPDM varies up to about 120 deg C.Be also aware that outer epoxy coating on the valve will have a much lower limitation, about max 70 deg centigrade outside temperature, or lower for difference inside/outside temperature. Above this outer epoxy will be miscolored and damaged.

MORE NEWS