Detail of GB/T 12604.5-2008

Introduction of GB/T 12604.5-2008

Codeofchina.com is in charge of this English translation. In case of any doubt about the contents of English translation, the Chinese original shall be considered authoritative. This standard replaces GB/T 12604.5-1990 Terminology for Non-destructive Testing — Magnetic Particle Testing. The following technical deviations have been made with respect to the GB/T 12604.5-1990 (the previous edition): — Terms and Definitions is modified (Clauses 2, 3 and 4 of Edition 1990; Clause 2 of this edition). This standard was proposed by China Machinery Industry Federation. This standard was prepared by SAC/TC 56 (National Technical Committee 56 on Non-destructive Testing of Standardization Administration of China). The previous editions of this standard are as follows: — GB/T 12604.5-1990. Non-destructive Testing — Terminology — Terms Used in Magnetic Particle Testing 1 Scope This standard defines terms used in magnetic particle testing as a common basis for standards and general use. 2 Terms and Definitions 2.1 A.C. electromagnet yoke yoke connected to the AC power 2.2 alternating current current whose magnitude and direction vary sinusoidally with time, is indicated by the symbol AC 2.3 alternating current field conductor is connected to an alternating current, and a magnetic field is induced inside and around the conductor 2.4 alternating current magnetization magnetization with a magnetic field generated by an alternating current inductor 2.5 ampere unit of current, abbreviated as A or amp 2.6 ampere per meter magnetic field strength at the center of the coil when a single-turn coil of 1 m in diameter is used in the air with a current of 1 A. Abbreviated as A•m-1 or A/m 2.7 ampere turns product of the number of turns of a coil and the current in amperes flowing through the coil   2.8 arc glow caused by discharge when an electric current passes through a gas clearance 2.9 arc strikes partial burn damage of a component due to poor electrical contact 2.10 axial current flow component is clamped along the axis between the two magnetic chucks of the flaw detector to allow current to flow directly through the component to be inspected, creating a closed circular magnetic field on the surface and inside of the component 2.11 black light ultraviolet light with a wavelength of 320 nm to 400 nm (3 200 Å to 4 000 Å), i.e. UV-A 2.12 black light filter filter that absorbs other wavelengths but allows near-ultraviolet transmission 2.13 cancel magnetic field when the ferromagnetic material is magnetized, the magnetic field generated by the magnetic poles in the material is a cancel magnetic field, which weakens the external magnetic field 2.14 central conductor electric conductor positioned in the centre of an aperture of the component is energized to form a circular magnetic field on the component after current flow 2.15 circular magnetic field magnetic field generated inside and around the component when current flow through the elongated conductor 2.16 circular magnetization current flows directly through the component or through the central conductor, generating a circumferentially closed magnetic field in the component that surrounds it and is perpendicular to it's long axis 2.17 circumferential magnetization see circular magnetization (2.16) 2.18 coercive force magnitude of the reverse magnetic field required to reduce the residual magnetic induction to zero 2.19 coil method method of wrapping a current carrying conductor coil around all or part of a component to make it fully or partially magnetized 2.20 coil shot technique in which a current is passed around a coil surrounding a component to magnetize it longitudinally 2.21 coil technique see coil method (2.19) 2.22 color magnetic particles white or other color magnetic particles made of industrial pure iron particles or other raw materials and coated with adhesive 2.23 rectified current alternating current is converted into a unidirectional current by a rectification method 2.24 contrast aid paints in order to improve the contrast between the magnetic particles display and the surface color of the component, a white suspension may be applied to the component surface before the flaw detection, and the suspension is called as contrast aid paints 2.25 contact head electrode for clamping the component to facilitate current flow   2.26 contact method see current flow techniques (2.31) 2.27 contact pad braid that is placed on the electrode to improve electrical contact and prevent arc strikes from the component, typically made of lead or copper 2.28 continuous technique procedure in which a component is magnetized while applying magnetic particles 2.29 crossed yoke magnetic particle inspection device that produces a rotating magnetic field on the same plane (or curved surface), two-phase sinusoidal alternating magnetic fields having a certain phase difference (not equal to 0° or 180°) and crossing each other at an angle (not equal to 0° or 180°) are superimposed on each other 2.30 curie point temperature at which the ferromagnetic material cannot be magnetized and the residual magnetic field disappears under the action of an external magnetic field (most metals are 650℃ to 870℃). 2.31 current flow techniques method of magnetizing a current through a component using a contactor or contact head; the current can be AC, DC or rectified 2.32 current induction technique by the action of the alternating magnetic field, a method of inducing a ring current in the annular component to realize magnetization is achieved 2.33 dark adaptation transient time of visual adjustments to the environments with reduced illumination 2.34 D.C. electromagnet yoke yoke connected to the DC power 2.35 demagnetization reduce the residual magnetic field of the magnetized ferromagnetic material or component to an acceptable level 2.36 demagnetization coil special coil for demagnetization 2.37 diamagnetic material materials with a relative magnetic permeability slightly less than 1 2.38 direct current current of constant in both size and direction and is represented by the symbol DC 2.39 direct current field residual magnet ic field or active magnetic field generated by a direct current passing through a conductor 2.40 magnetic domain small area of spontaneous magnetization that exists inside the ferromagnetic material 2.41 dry method method of magnetic particle detection using dry magnetic powder 2.42 dry magnetic powder dry, particulate, magnetic powder of suitable size and shape for detecting discontinuities 2.43 electrode conductor that introduces electrical current into or out of a component 2.44 electromagnet soft iron core wound around a coil becomes a temporary magnet as current passes through the coil   2.45 effective magnetic field effective magnetic field on the component is equal to the applied magnetic field minus the cancel magnetic field 2.46 electricity magnet magnet that requires a power source to maintain its magnetic field 2.47 ferromagnetic material material with relative magnetic permeability is much greater than 1, which varies with the magnetic field strength 2.48 fill factor ratio of the cross-sectional area of the coil to the cross-sectional area of the component when magnetized by the coil method 2.49 fixed installations fixed flaw detector has a large volume and weight, and the rated circular magnetization current is generally from 1 000 A to 10 000 A 2.50 flash magnetization magnetization of current flow in a short time 2.51 flash point the lowest temperature at which the volatile inflammable substances or the vapor in the air generated by volatilization of inflammable substance is ignited by the flame 2.52 flexible coil cable winding magnetization using a cable wrapped closely around a component 2.53 fluorescent visible light emitted by a substance due to its absorption of ultraviolet light   2.54 fluorescent magnetic particles magnetic particles formed by coating a layer of a fluorescent substance on the outer surface of the ferromagnetic particles 2.55 fluorescent magnetic particles testing method of detecting fluorescent magnetic particles by observation with a black light 2.56 flux density see flux density (2.85) 2.57 flux leakage field after the magnetization of the ferromagnetic material, magnetic field formed by the magnetic induction line leaving and entering the surface at the discontinuity or the change in the cross section of the magnetic circuit 2.58 flux meter electronic device for measuring magnetic flux 2.59 full-wave direct current penetrating and directional DC currents obtained by single-phase or three-phase AC rectification 2.60 tesla unit of flux density or magnetic induction strength can be abbreviated as T. A 1 m long conductor perpendicular to the direction of the magnetic field passes through a current of 1 A. When the force of the magnetic field is 1 N, the magnetic induction strength at the place where the energized wire is located is 1 T 2.61 tesla meter magnetometer that reads the field strength in tesla 2.62 half-wave rectified current half-cycle cut-off current in the opposite direction obtained by single phase A.C. through single-phase rectification; it is used for unidirectional magnetic field to generate pulses 2.63 heads clamp attached to the desktop magnetic particle testing device 2.64 high permeability ferromagnetic materials are strongly magnetized in an external magnetic field, producing a very strong additional magnetic field 2.65 hysteresis when the direction of the external magnetic field changes, the change in the magnetic induction strength lags behind the change in the magnetic field strength 2.66 hysteresis loop curve describing the relationship between flux density and magnetic field strength 2.67 shot impact current current generally obtained by charging and discharging of the capacitor 2.68 induced current flow inductive current method is to insert the iron core into the ring-shaped component, and use the component as the secondary coil of the transformer to generate a circumferential induced current in the component through the change of the magnetic flux in the iron core

Contents of GB/T 12604.5-2008

Foreword II 1 Scope 2 Terms and Definitions English Index