| Design reference | API RP520 |
| Structural length | API 526 |
| Flanged ends | ASME B16.5a |
| Test &inspection | API527 |
Note: The dimension of connecting flange can be designed according to customers’ requirements.
| No. | accessory name | Sign of Materials | ||||||||
| C | C6 | S | SM | SL | Mc | M | H | |||
| 1 | Body | WCB | WC6 | CF8 | CF8M | CF3M | WCB | Monel | Hast.C | |
| 2 | Seat | 304/316 | 304/316 | 316 | 316L | 316L | Monel | Monel | Hast.C | |
| 3 | Adjust ring | CF8 | CF8 | CF8M | CF8M | CF3M | CF8M | Monel | Hast.C | |
| 4 | Valve Clack | 304 | 304 | 316 | 316L | 316L | 630 | Monel | Hast.C | |
| 5 | Valve Clack Holder | 420 | 420 | 630 | 630 | 316L | 316L | Monel | Hast.C | |
| 6 | Guide | 304 | 304 | 304 | 316 | 316L | 316 | Monel | Hast.C | |
| 7 | Spring Seat | WCB | WCB | 420 | 420 | 420 | 420 | 420 | 420 | |
| 8 | Spring | 50CrVA | ||||||||
| 9 | Stem | 420 | ||||||||
| 10 | Bonnet | WCB | WC6 | CF8 | CF8M | CF3M | WCB | Monel | Hast.C | |
| 11 | Bellows | 316L | Monel | Hast.C | ||||||
Note: Major parts of the valve series and materials of sealing surface differ according to casual working condition and customers' special requirements.
