Why investment casting
Valve, pump and wellhead components in duplex, super duplex and nickel alloys are cast with the testing and documentation that pressure and sour service demand.
Components
- Valve bodies and trim
- Choke and flow-control parts
- Downhole tool components
- Instrumentation fittings
Materials
Duplex and super duplex, CA6NM, nickel alloys, low-alloy steels.
Frequently used alloys
| Grade | Type | Standard |
|---|---|---|
| WCB | Weldable carbon steel for pressure parts A216 WCB | ASTM A216/A216M |
| CF8M | Mo-bearing austenitic stainless steel, cast 316 type 316 type | ASTM A351/A351M, A743/A743M |
| CD3MN (4A) | 22Cr-5Ni-Mo-N duplex stainless steel 2205 type (Uranus® 45N, SAF 2205®) | ASTM A890/A890M, A995/A995M Gr. 4A |
| CE3MN (5A) | 25Cr-7Ni-Mo-N super duplex stainless steel 2507 type (SAF 2507®) | ASTM A890/A890M, A995/A995M Gr. 5A |
| CW-6MC | Ni-Cr-Mo-Nb alloy, cast Alloy 625 type Inconel® 625 type | ASTM A494/A494M |
Typical requirements
Sour-service hardness limits, impact toughness, corrosion testing and third-party inspection are common contractual requirements.
- Hardness limits for sour service
- Corrosion and ferrite testing
- Third-party inspection 3.2
Related engineering topics
Documentation
Documentation for investment castings: EN 10204 inspection documents 2.1, 2.2, 3.1 and 3.2, material certificates, dimensional and NDT reports, heat-treatment records and traceability.
Non-destructive testing
NDT methods for investment castings: liquid penetrant, magnetic particle, radiographic and ultrasonic testing, computed tomography, leak testing, personnel qualification and acceptance levels.
International equivalents
How to compare cast alloy designations across EN, DIN, ASTM, ASME, UNS, AISI, SAE, JIS, ISO and GB/T, and why similar grades are not automatically interchangeable.