Zhejiang Guanyu Steel Tube Co., Ltd.
Zhejiang Guanyu Steel Tube Co., Ltd. has been serving global customers since 2003. The company has passed multiple certifications, including:
- China Special Equipment Manufacturing License TS-A & B
- EU Pressure Equipment Directive PED 2014/68/EU
- ISO 9001 International Quality Management System
- ISO 14001 Environmental Management System
- ISO 45001 Occupational Health and Safety Management System
Overview
Guanyu Steel Tube is a specialized manufacturer of high-quality stainless steel tubes and pipes as well as nickel alloy tubing and pipes. The production area covers 35,000 square meters with an annual output capacity exceeding 10,000 metric tons.
Quality Management
The company has established a complete quality management system aligned with ISO 9001:2015 and PED 2014/68/EU. Quality control begins with an audit trail of raw materials, selecting the best materials, and continues through all stages of production. Finished products undergo destructive and non-destructive testing according to standard specifications and customer requirements, including verification by independent third-party test houses.
Production Range
- Outer diameter (OD): 1–530 mm
- Wall thickness (WT): 0.5–65 mm
- Length: Up to 25,000 mm
Material Grades
Guanyu produces a wide variety of stainless steel, duplex steel, and nickel alloys, including:
- Austenitic stainless steels: 304, 304L, 304H, 309S, 310S, 321, 321H, 316, 316L, 316H, 316Ti, 317L
- Duplex & super duplex steels: SAF1805, SAF2205, S31803, SAF2507, S32760
- High nickel and alloy tubes: 904L, Ni6, 800H, 625, 825, 600, 400, 4J29, 4J36, GH3030, GH3039
- Other special grades: 06Cr19Ni10, 022Cr19Ni10, 07Cr19Ni10, 06Cr25Ni20, 07Cr25Ni21NbN, 06Cr17Ni12Mo2, 022Cr17Ni12Mo2, 07Cr17Ni12Mo2, 06Cr17Ni12Mo2Ti, 06Cr19Ni13Mo3, 022Cr19Ni13Mo3, 06Cr18Ni11Ti, 07Cr19Ni11Ti, 06Cr18Ni11Nb, 07Cr18Ni11Nb, 16Cr20Ni14Si2, 022Cr23Ni5Mo3N, 022Cr25Ni7Mo4N
Application Standards
- China: GB/T 14976, GB/T 13296, GB/T 21833
- Europe: EN 10216-5, DIN 17456 / 17458 / 17459
- ASTM / ASME: ASTM A213/A312/A269/A789/A790/A511/A376/A688, ASME SA213/SA312/SA269/SA789/SA790/SA511/SA376, ASTM B163/B165/B167/B338/B407/B423/B444/B619/B622/B626/B668/B677/B829
- Japan: JIS G3459, JIS G3463
- Russia: GOST 9940, GOST 9941
Industries Served
Guanyu Steel Tube products are widely used in petroleum, chemical, aerospace, shipbuilding, nuclear power, pharmaceuticals, high-pressure boilers, heat exchangers, and other industrial applications, providing safe and high-performance solutions for demanding environments.














