UNS S41426 and HP-2, the Super 13 Chrome alloys, are martensitic stainless steels that have been quenched and tempered. Their purpose is to provide corrosion resistance in conditions that are sweet (CO2) and mildly sour (H2S) with a moderate chloride concentration, up to 350°F.
Compared to regular 13 Chrome, super 13 Chromes have better mechanical qualities and are more resistant to the effects of CO2, H2S, chlorides, pH, and temperatures. They can be used as downhole tube components, packers, and other subsurface equipment in deeper wells with high pressure and high temperature (HPHT) conditions due to their greater strength and temperature resistance compared to 13 Chrome L80. Super 13 Chromes can be used in mildly sour conditions since they are more resistant to H2S and chlorides than Modified 13 Chrome.
- Applications for Gas and Oil in Upstream
- Conditions that are corrosive and contain CO2 and H2S < 1.5 psi Tubing
- Closing Lines
- Sand screen base pipe
- Extensions
- Guns with Perforations
- Joints of Landing Extensions
- envelops maker joints
- VIT Swell Packers Pipe
- Carbon Capture and Sequestration (CCS) with Geothermal Power
- Chemical Composition
The grade offers improved mechanical qualities and corrosion resistance and is derived from the regular 13Cr grade. While preserving the martensitic microstructure, the low carbon makes the material more weldable.
| Weight % | C | Si | Mn | Cr | Ni | Mo | Cu | N | Ti | V | S | P | |
| Min. | S41425 | 0,50 | 12,00 | 4,00 | 1,50 | 0,06 | |||||||
| Max. | 0,05 | 0,50 | 1,00 | 15,00 | 7,00 | 2,00 | 0,30 | 0,12 | 0,005 | 0,020 | |||
| Min. | S41426 | 11,50 | 4,50 | 1,50 | 0,01 | ||||||||
| Max. | 0,03 | 0,50 | 1,00 | 13,50 | 6,50 | 3,00 | 0,50 | 0,50 | 0,005 | 0,020 |
- Product Standards: 95ksi or 110ksi yield strength, mid radial material.
- Approvals: NACE MR 0175 for 95ksi type.
| Yield strength Rp0.2, MPa | Tensile strength Rm, MPa | Elongation [%] | Hardness [HRC] | Impact, Charpy-V, -10ºC [J] | ||
| S41425 | Min. | 750 (110 ksi) | 862 (125 ksi) | ≥ 16 | ≥ 60 | |
| Max. | 862 (125 ksi) | ≤ 32/33 | ||||
| S41426 | Min. | 655 (95 ksi) | 724 (105 ksi) | ≥ 18 | ≥ 60 | |
| Max. | 724 (105 ksi) | ≤ 27 |
- Applications:
- Downhole completion tools (e.g., offset mandrels, packers, safety valves)
- Corrosion Resistance:
- Suitable for limited NACE sour service environments
- Excellent resistance to CO2 and chlorides
- Availability:
- 95 ksi yield condition (limited NACE sour service)
- 110 ksi version (standard and CO2 oilfield environments)