Butt welding elbow can produce corrosion phenomenon in incorrect use. After the corrosion of butt welding elbow, it is usually manifested as the tube wall of butt welding elbow thinning, local pits and pitting. Butt welding elbow detection method after corrosion: The basic principle of flux leakage detection is based on the basic characteristics of high permeability of ferromagnetic materials.
The magnetic conductivity of butt welding elbow corrosion defects is far less than that of butt welding elbow. Butt welding elbow is magnetized under the action of external magnetic field. When there is no defect in butt welding elbow, most of the magnetic force lines pass through steel pipe, and the magnetic force lines are evenly distributed. When there is a defect inside the butt elbow, the magnetic field lines bend and part of the magnetic field lines leak out of the surface of the steel pipe. The existence of defects can be determined by detecting the flux leakage escaping from the surface of the magnetized butt welding elbow. Ultrasonic method Ultrasonic method is to use the pulse reflection principle of ultrasonic wave to measure the thickness of the tube wall after corrosion. The process adopts the method of self-spreading centrifugal casting molding, mainly using the chemical reaction of the material itself, exothermic combustion produces high temperature, and the technology of synthesizing new substances in the process of combustion wave spreading. When detecting, the probe emits ultrasonic pulse vertically to the inner wall of butt welding elbow. The probe first receives the reflected pulse from the inner surface of the tube wall, and then the ultrasonic probe receives the reflected pulse from the outer surface of the tube wall. The distance between the pulse and the reflected pulse of the inner surface reflects the thickness of the tube wall. Bending: refers to the pipe processing into butt welding elbow, generally refers to the professional metal pipe and electrical PVC threading pipe hydropower; Butt welding elbow: it refers to metal butt welding elbow of water supply and drainage specialty. Butt welding elbow of small pipe diameter can be obtained by bending