YUHONG GROUP has more than 35 years of experience in supplying seamless and welded steel pipes and tubes in carbon steel, austenitic stainless steel, duplex stainless steel, and nickel alloys, including Hastelloy, Monel, Inconel, and Incoloy. Our annual sales volume exceeds 80,000 tons, and our products have been supplied to customers in more than 85 countries. Our group companies and manufacturing facilities have obtained applicable international certifications and approvals, including CE, TÜV, LR, ABS, DNV, BV, KR, PED, AD 2000, CCS, TS, CNNC, ISO 9001, ISO 14001, OHSAS 18001, and ISO 45001.
| Element | Requirement |
|---|---|
| Carbon C | 0.020 percent maximum |
| Manganese Mn | 2.00 percent maximum |
| Phosphorus P | 0.045 percent maximum |
| Sulfur S | 0.030 percent maximum |
| Silicon Si | 1.00 percent maximum |
| Chromium Cr | 19.00 to 23.00 percent |
| Nickel Ni | 23.00 to 28.00 percent |
| Molybdenum Mo | 4.00 to 5.00 percent |
| Copper Cu | 1.00 to 2.00 percent |
| Nitrogen N | 0.10 percent maximum |
| NPS Designator | Over Tolerance from Nominal | Under Tolerance from Nominal |
|---|---|---|
| NPS 1/8 to NPS 2 1/2 inclusive all t D ratios | 20.0 percent | 12.5 percent |
| NPS 3 to NPS 18 inclusive t D up to and including 5 percent | 22.5 percent | 12.5 percent |
| NPS 3 to NPS 18 inclusive t D greater than 5 percent | 15.0 percent | 12.5 percent |
| NPS 20 and larger welded all t D ratios | 17.5 percent | 12.5 percent |
| NPS 20 and larger seamless t D up to and including 5 percent | 22.5 percent | 12.5 percent |
| NPS 20 and larger seamless t D greater than 5 percent | 15.0 percent | 12.5 percent |
UNS N08904 pipe shall be supplied in the heat-treated condition.
The minimum heat-treatment temperature specified for N08904 is 2000 degrees Fahrenheit or 1100 degrees Celsius. The pipe shall be quenched in water or rapidly cooled by another suitable method after reaching the required heat-treatment condition.
Heat-treatment control can include:
The final heat-treatment condition shall be stated on the Material Test Certificate when required by the purchase order.
Available documentation can include:
The certification shall identify whether hydrostatic testing was performed or which nondestructive electric examination method was used.
Document language, format, number of copies, electronic submission requirements, and purchaser approval sequence shall be stated in the purchase order.
ASME SA312 UNS N08904 904L seamless stainless steel pipe is used in:
