文档介绍：中华人民共和国国家标准
National Standard of the People’s Republic of China
GB 6479-2000
neq ISO 9329-2:::1997
Supersedes GB 6479-1986
高压化肥设备用无缝钢管
Seamless steel tubes for high-pressure
For chemical fertilizer equipments
Approved by the State Bureau of Technical Supervision on 2000–10- 25 Implemented from 2001 – 09 – 01
GB 6479 – 2000
Foreword
This Standard is not equivalent to adopt ISO 9329 – 2:1997 Seamless Steel Tubes for
Pressure Vessels ---- Delivery Specifications ---- Part 2: Carbon Steel and Alloy Steel of
Specified High Temperature Performance.
The criteria of allowable deviation for size, degree of bend, press-flat deformation coefficient
for steel tubes in this Standard are more strict than international criteria while the criteria of
physical performance is equivalent to international ones.
This Standard, compared with original edition, has made revision to following provisions:
1. The criteria of allowable deviation for size are revised. Original Table 1 is deleted. The
specification for the size is changed to refer to Table 1 of GB/T 17395 – 1998.
2. The brand number of 12SiMoVNb is added. Phosphorous and sulfur content in different
brand numbers of steel is revised.
3. Supplementation is made to the delivery status of steel tubes.
4. The provision of using leaking ic testing to replace hydraulic test is added while
the provision of using ultrasonic testing to replace hydraulic test is deleted.
5. The stipulations of making press-flat test to steel tubes with OD > 400mm is deleted.
6. The requirements for low-fold inspection for steel tubes rolled of steel ingot is added as
well as the requirements for inspection of non-metal inclusion in steel tubes rolled of
continuous cast blank and steel ingot.
7. Definite stipulations are made for the class of ultrasonic testing.
From the date of implementation, this Standard shall supercede GB 6479 – 1986