摘要:
An information recorded medium (10) comprising a base (2a), a resin layer (2) provided on the base (2a), a hologram region (6) comprising a diffraction grating (4) provided regularly or irregularly on the resin layer (2), and a ferromagnetic thin film layer (3) formed on the hologram layer (6) and holding as management information for forgery prevention a magnetic characteristic which corresponds to the hologram pattern of the hologram region (6) and can be read as a signal pattern corresponding to the hologram pattern.
摘要:
L'invention concerne un procédé d'inspection d'un tronçon de canalisation (T) s'étendant en dessous d'une surface (S sol ) de sol selon un axe longitudinal (Y). Le procédé comprenant les étapes suivantes : - enregistrer, à l'aide de magnétomètres (M 1 , M 2 , M 3 , M 4 ) agencés au-dessus de la surface de sol et du tronçon de canalisation, des premiers signaux (S 1 ), les magnétomètres étant alignés selon un axe orthogonal à l'axe longitudinal du tronçon de canalisation et parallèle à la surface de sol ; - générer, à l'aide d'une première bobine (C, C 1 , C 1 ') parcourue par un premier courant (I, I 1 , I 1 ')présentant au moins une première valeur (I min , I v1 ) non nulle et une deuxième valeur (I max , I v2 ) non nulle et différente de la première valeur, un premier champ magnétique additionnel (F c , F c1 , F c1 ') ; - enregistrer, à l'aide des magnétomètres, des deuxièmes signaux (S 2 ) ; - déduire des premiers et deuxièmes signaux l'existence d'au moins un défaut dans le tronçon de canalisation.
摘要:
The invention relates to a sensor (5) for detection and/or monitoring the growth of defects, in particular cracks (2), in ferromagnetic structures (1), such as civil engineering and marine structures, comprising a plurality of magnetometers (4) for measuring magnetic flux leakage (MFL), which magnetometers (4) are arranged in a plane, and a support (7) carrying the magnetometers (4). The sensor (5) comprises a layer (6) of a magnetically permeable material extending over and/or between the magnetometers (4).
摘要:
The present invention is directed to a system and a method for inspecting a subsea pipeline. The method comprises the steps: detecting a defect along the subsea pipeline using a subsea magnetometric tomography method (MTM) module adjacent the subsea pipeline; and determining a position of the subsea MTM module, thereby determining the position of the defect. The method further comprises determining the position of the subsea MTM module relative to a surface vessel; and determining an absolute position of the surface vessel.
摘要:
This utility model relates to the field of magnetic flaw detection, to devices for non-destructive testing of pipelines, and, in particular, to a magnetic system for an in-pipe flaw detector. The technical effect of the claimed utility model consists in decreasing mutual influence of main belts of magnetic modules and improving uniformity of magnetic field distribution in circumferential and longitudinal directions. The magnetic system for transverse magnetization having fixed magnetic modules and designed for an in-pipe flaw detector consists of two main and four additional belts of magnetic modules, which are arranged on two magnetic conductors connected with a non-magnetic insert. Each magnetic module consists of permanent magnets and wire brushes that transfer a magnetic flux into the pipeline wall. Magnetic modules that are adjacent to each other in a belt have opposite directions of a magnetic field in an interpolar space. The main poles of magnetic modules are angularly offset relative to each other. The additional belts of magnetic modules are arranged at the edges of the main belts of magnetic modules, two additional magnetic modules being arranged between the belts of main magnetic modules and serving for compensating mutual influence of a magnetic field generated by the main magnetic modules and for decreasing non-symmetry of the magnetic field, which is caused by close location of the main poles. Each additional belt of magnetic modules serving for correcting non-symmetry of the field is angularly offset relative to a main magnetic belt.