3-8 EB 3018 ENDesign and principle of operationTable 3-2: Materials · Material number according to DIN ENType 2423 E Valve balanced by a bellowsPressure rating PN 16 PN 25 PN 16, 25 and 40Valve body Cast ironEN-GJL-250Spheroidal graphiteironEN-GJS-400-18-LTCast steel1.0619Cast stainlesssteel 1.4408Forged stainlesssteel 1.4571 1)Seat 1.4104, 1.4006 1.4404Plug Up to DN 100 1.4104, 1.4006 2) 1.4404DN 125 to 250 1.4301, 1.4404 with PTFE sealPlug stem 1.4301Metal bellows 1.4571 · DN 125 and larger: 1.4404Bottom section P265GH 1.4571Body gasket Graphite on metal coreType 2423 E Valve balanced by a diaphragmPressure rating PN 16 PN 25 PN 16, 25 and 40Valve body Cast ironEN-GJL-250Spheroidal graphiteironEN-GJS-400-18-LTCast steel1.0619 6)Cast stainlesssteel 1.4408 6) –Valve seat Red brass 3) 4)Plug (standard version) Red brass 3) 5) · With EPDM soft seal, max. 150 °C or with PTFE soft seal, max.150 °CPressure balancing Balancing cases made of sheet steel DD11 · EPDM balancing diaphragm, max.150 °C or NBR diaphragm, max. 80 °CType 2426 ActuatorDiaphragm cases 1.0332 1.4301Diaphragm EPDM with fabric reinforcement · Special version for mineral oils: FKMGuide bushing DU bushing PTFEType 5824 and Type 5825 Electric ActuatorsHousing, housing cover Plastic (PPO with glass fiber reinforcement)Coupling nut Brass1) DN 15, 25, 40 and 50 only2) Optionally with soft seal with standard KVS coefficients3) Special version 1.44094) DN 65 to 100: 1.40065) DN 65 to 100: 1.4104/1.40066) DN 125 to 250 only