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, including the United States, Canada, Chile, Colombia, Saudi Arabia, South Korea, Singapore, Australia, Poland, and France. 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 | 0.06 to 0.18 % |
| Manganese | 0.27 to 0.63 % |
| Phosphorus | 0.035 % maximum |
| Sulfur | 0.035 % maximum |
The tubes are manufactured by the seamless process and cold drawn. After the final cold drawing pass the base tubes are heat treated at a temperature of at least 650 degrees Celsius.
The finished tubes shall have a clean surface condition and shall be free from harmful scale and visible defects. A slight amount of surface oxidation may be accepted according to the applicable standard and purchase order.
The maximum hardness requirement for the SA179 base tube is 72 HRBW.
Flattening flaring hardness and other required mechanical tests are carried out according to the applicable lot requirements. Product analysis can be provided when specifically requested in the purchase order.
Each base tube is subjected to hydrostatic testing unless a permitted nondestructive electric test is specified as a substitute by the purchaser.
ASME SA179 seamless cold drawn carbon steel U bend tubes are used in:
The U bend radius, straight leg length, tube pitch, tube arrangement, and quantity for each radius are manufactured according to the approved heat exchanger tubesheet layout and equipment drawing.
