GB/T 37910.1-2019Non-destructive testing of welds -- Acceptance levels for radiographic testing -- Part 1: Steel, nickel, titanium and their alloys (English PDF)

1 Scope

This Part of GB/T 37910 specifies acceptance levels for indications from imperfections in butt welds of steel, nickel, titanium and their alloys detected by radiographic testing.

If agreed, the acceptance levels can be applied to other types of welds or materials.

The acceptance levels can be related to welding standards, application standards, specifications or codes. This Part assumes that the radiographic testing has been carried out in accordance with GB/T 3323.1 or GB/T 3323.2. When assessing whether a weld meets the requirements specified for a weld quality level, the sizes of imperfections permitted by standards are compared with the dimensions of indications revealed by a radiograph made of the weld.

2 Normative references

The following referenced documents are indispensable for the application of this document. For dated references, only the edition dated applies to this document. For undated references, the latest edition of the referenced documents (including all amendments) applies to this document.

GB/T 3323.1, Non-destructive testing of welds - Radiographic testing - Part 1: X- and gamma-ray techniques with film (GB/T 3323.1-2019, ISO 17636-1:2013, MOD)

GB/T 3323.2, Non-destructive testing of welds - Radiographic testing - Part 2: X- and gamma-ray techniques with digital detectors (GB/T 3323.2-2019, ISO 17636-

2:2013, MOD)

GB/T 6417.1, Welding and allied processes - Classification of geometric imperfections in metallic materials - Part 1: Fusion welding (GB/T 6417.1-2005,

ISO 6520-1:1998, IDT)

GB/T 32259, Non-destructive testing of welds - Visual testing of fusion-welded joints (GB/T 32259-2015, ISO 17637:2003, MOD)

- A sum of projected areas of indications related to each L × Wp , in % (see Annex

B);

- b width of excess penetration of weld, in millimetres;

- d diameter of pore, in millimetres;

- dA diameter of pore envelope area, in millimeters;

- h width of indication, the width or height of surface imperfection, in millimetres;

- L any 100 mm testing length, in millimeters;

- l length of indication, in millimetres;

- s nominal butt weld thickness, in millimetres;

- t base material thickness, in millimetres;

- Wp width of the weld, in millimetres;

- sigmal summary length of imperfections within L, in millimetres.

If the interval between any two adjacent imperfections is less than or equal to the main dimension of the smaller imperfection, they shall be deemed to be one imperfection.

For the calculation of accumulative areas of imperfections see Annex C.

Indications shall not be divided into different Ls.

Annex A (Informative)

Guide to the limitations of radiographic testing