The possible defects of groove include delamination and crack. The former is rolling defect, which is parallel to the surface of steel plate and is generally distributed near the center of plate thickness.  There are two kinds of cracks, one is along the layered end crack, the direction is mostly parallel to the plate surface;  The other is flame cutting crack.

X-ray Orientation Analyzer is developing towards smaller volume, lighter weight, higher energy conversion efficiency, stronger penetration ability and better stability.  The high frequency constant voltage technology has shown us the dawn, but we still use the frequency conversion technology 30 years ago, the difference is very big.  The scope of groove flaw detection is groove and blunt edge.

Interlayer flaw detection: for some steel grades with poor welding performance, it is required to conduct inspection once for each layer of welding. if cracks are found, they shall be handled in time, and welding shall be continued after no defects are confirmed.  Another case is the welding of extra-thick plates. When it is difficult to inspect internal defects, X-ray inspection can be performed once for each layer welded.

The scope of flaw detection is weld metal and adjacent groove.  Flaw detection of arc gouging surface: the purpose is to check the cracks caused by surface carbonization caused by arc gouging.  The scope of flaw detection shall include arc gouging surface and adjacent groove.  The purpose of weld flaw detection is mainly to inspect welding defects such as welding cracks.

The scope of flaw detection shall include the heat affected zone of weld metal and base metal, and the width of the heat affected zone is about half of the width of weld.  Therefore, it is required that the width of flaw detection should be twice the weld width.  Before you use the flaw detector for testing, you must first carry out a careful inspection of flaw detection equipment. Only those equipment that are in a complete state can be used for inspection.

In order to prevent non-professional personnel from operating this type of equipment, special personnel must be assigned to take care of the equipment and put up warning signs.  Before using any flaw detection equipment, it is required to undergo strict and formal flaw detection operation training, and then it is required to operate according to the formal flaw detection operation process. During flaw detection, the radiation dose must be strictly controlled.