China Standardgb T 158221 2005 Non Destructive Testing Magnetic Particle Testing Part 1general Principles PDF Download

This document specifies the requirements for magnetic particle inspection of seamless and welded ferromagnetic steel tubes for surface imperfections on the tube body and imperfections on the end face/bevel at the tube ends. This document specifies the requirements for the detection of imperfections on the outer surface of all or part of steel tubes. Upon negotiation and agreement between the purchaser and the manufacturer, it can be applied to the detection of the inner surface over a limited length from the tube end (depending on the diameter of the steel tube). When applicable, this document can be used to locate the position of the external surface imperfections detected by other non-destructive testing (such as ultrasonic) methods before grinding, and to confirm that the imperfections have been completely removed after grinding. This document specifies the requirements for the detection of laminar imperfections on the end face/bevel at both ends of plain-end tubes and beveled-end tubes that may affect subsequent manufacturing and testing (such as welding and ultrasonic testing of welds). This document applies to the detection of laminar imperfections and other imperfections on the end face/bevel. In this case, the direction of the magnetic field shall be as perpendicular to the direction of the imperfection being detected as possible. This document also applies to the inspection of hollow parts.