SY/T 6423.4-1999 (English Version) PDF

Scope: 1.1 This standard specifies the Super Lubo inspection requirements for delamination defects near the welds of pressure-bearing welded steel pipes according to three different acceptance levels (see Table 1). The purpose of this standard is to detect delamination defects and/or weld defects near welds that may affect the integrity of the weld. Note 1: This test can also be carried out in accordance with the provisions of SY/T 6423.5. Ultrasonic testing can be carried out on the longitudinal edges of flattened steel strips/steel plates (used to manufacture welded steel pipes) before welding. 1.2 This standard is applicable to the testing of welded steel pipes with a nominal outer diameter greater than 30mm. The lower limit of steel pipe wall thickness is not specified, see Note 2. Note 2: For steel pipes with a nominal wall thickness less than 5 mm, difficulties may be encountered when using this method to detect and determine the size of delamination defects. When this happens. The purchaser and manufacturer are required to negotiate to determine the testing method to be used.

SY/T 6423.4-1999 history

2013 SY/T 6423.4-2013 Petroleum and natural gas industries.Non-destructive testing (NDT) methods of steel tubes.Part 4: Automated ultrasonic testing of seamless and welded steel tubes for the detection of laminar imperfections
1999 SY/T 6423.4-1999 Petroleum and natural gas industries.Non-destructive testing (NDT)methods of steel tubers for pressure purposes.Ultrasonic testing of the area adjacent to the weld seam of welded steel tubes for the detection of laminar imperfections