For the selected media "Sodium hydroxide" it's recommended to use the following disk materials: iron GGG40/GG25, carbon steel WCB, stainless steel with molybdenum CF8M, aluminum-bronze, and the following seats materials: stainless steel with molybdenum CF8M, NBR, PTFE. Also in some cases it's allowed to use rather stable materials. As for disks they are: stainless steel CF8, and as for the seats: EPDM, stainless steel CF8.
You can choose the butterfly valves of PromArm manufacturing from our catalog.
| Disk material | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Concentration | Ductile iron | Carbon steel | stainless steel CF8 | stainless steel CF8M | Aluminum-bronze | |||||
| <10% | A | A | - | A | A | |||||
| 30% | B | C | B | B | B | |||||
| 50% | B | C | B | C | C | |||||
| 70% | B | C | C | C | C | |||||
| Seat material | ||||||||
|---|---|---|---|---|---|---|---|---|
| Concentration | EPDM | NBR | CR | Natural rubber | SILICONE | FKM (Viton) | FFKM | PTFE |
| <10% | B | A | A | A | A | B* | A | A |
| 30% | B | A | B | B | A | B* | A | A |
| 50% | B | B | B | B | B | B* | A | A |
| 70% | C | B | C | B | B | B* | A | A |
where: A - excellent, B - good, C - not recommended, * - inaccurate data