Function and standard of NDT for welded workpieces

Date：2021-12-13 16:33:00Views：2123

Penetrant testing is a non-destructive testing method based on the principle of capillary action to inspect surface opening defects. Penetrant testing can be used to detect the surface opening defects of metal and non-metal workpieces, which is not affected by the structure, chemical composition and defect shape of the inspected workpieces. However, conventional penetrant testing cannot or is difficult to inspect porous materials, and is not suitable for detecting defects that the opening is blocked due to external factors. Because of its simplicity and easy operation, penetrant testing is widely used in various fields of modern industry.

The main application of penetrant testing is to inspect the surface opening defects of metal (steel, aluminum alloy, magnesium alloy, copper alloy, heat-resistant alloy, etc.) and non-metallic (plastic, ceramic, etc.) workpieces, such as surface cracks.

Penetrant nondestructive testing and Pt penetrant testing of weldments: the basic principle of dye (penetrant) testing is to use capillarity to make the penetrant penetrate into the defect, remove the surface penetrant after cleaning, and absorb the residual penetrant in the defect by using the capillary action of developer to detect the defect.

Penetrant nondestructive testing and dye penetrant testing of weldments belong to one of the methods of nondestructive testing, which is to apply penetrant on the cleaned workpiece surface. If there is a defect, the penetrant will penetrate into the defect. Then wash the excess penetrant on the surface of the workpiece, and then apply the developer. Due to capillarity, the residual penetrant in the defect is sucked out. Although the dye penetrant flaw detection method has low accuracy compared with other detection methods, due to its simple operation and no special device, it can obtain satisfactory flaw detection results only by preparing or purchasing appropriate dye penetrant flaw detection agent and using it in strict accordance with certain methods. Therefore, it is still often used to detect the surface defects of welded parts.

Scope of application:

Penetrant nondestructive testing of weldments, applicable to testing parts of various metallic and non-metallic materials, including parts made of various iron and steel materials, aluminum alloy, magnesium alloy, titanium alloy, FRP, glass, plastic, ceramics, etc;

It is suitable for testing various cold and hot processed parts, including castings, weldments, forgings, extrusions, heat treated parts, surface treated parts, various machined parts, etc;

It is applicable to the inspection of raw material samples, parts in process, finished parts and parts in service.

Penetrant nondestructive testing and penetrant testing of weldments can be used as a supplement to magnetic particle testing. For non-magnetic materials such as aluminum weldments, Pt penetrant testing is better.

The following NDT standards for welded workpieces at home and abroad compiled by the core testing team are for your reference only:

JB / t6062 penetrant inspection method for welds and classification of defective magnetic traces

Iso10675-2 nondestructive testing of welds - Part 2: evaluation and acceptance level of radiographic testing of aluminum alloy products

GB / t3323 radiography of metal fusion welded joints

ASTM E390 standard radiograph for fusion welding of steel

ISO 5817 incomplete quality classification of fusion welded joints of weld steel, nickel, titanium and their respective alloys (except beam welding)

GB / t11345 manual ultrasonic testing methods for steel welds and classification of test results

Jisz3081 ultrasonic bevel flaw detection method for aluminum pipe welds and classification method of inspection results

JB / t9212 ultrasonic flaw detection for welds of atmospheric steel oil tank

ISO 17636-1 non destructive testing of welds X-ray and gamma ray film techniques

GB / t12605 radiographic technology and quality classification of circumferential fusion welded butt joints of steel pipes

JB / t6061 magnetic particle testing method for welds and classification of defective magnetic traces

Iso17638 non destructive testing of welding magnetic particle testing of welded joints

Nb / t47103 nondestructive testing of pressure equipment

GB / t14693 symbols for nondestructive testing of welds

ASTM e1032 radiographic testing method for weldments

GB / t15830 ultrasonic testing methods and classification of test results for butt circumferential welds of steel pipes

Iso11666 non destructive testing of welds acceptance level of ultrasonic testing of welded joints

TB / t1558 ultrasonic flaw detection for butt welds

Iso10042 incomplete quality classification of welded aluminum and its alloy arc welded joints

Iso10675-1 nondestructive testing of welds - Part 1: evaluation and acceptance level of radiographic testing of steel, nickel, titanium and their alloy products

Jisz3080 ultrasonic bevel flaw detection method for aluminum welds and classification method of inspection results

Iso17640 nondestructive testing of welds ultrasonic testing technology, acceptance level and result evaluation

Iso17636-2 nondestructive testing of welds X-ray testing and gamma ray electronic imaging technology

Iso3452 nondestructive testing Penetrant testing

Iso23278 non destructive testing of welds magnetic particle testing acceptance level of welded joints

Jisz3105 radiographic inspection method and film rating method for aluminum welds

ASTM e1648 radiographic reference film for aluminum fusion welding inspection

Iso23277 nondestructive testing of welds acceptance level of penetrant testing of welds