Elbow finishing plant, whether it is stamping elbow, elbow or push the system, or large diameter elbow, when it corrosion how to do it? And how it was detected corrosion of it? Elbow in the use of certain an important role and performance, in the course of maintenance and need to be detected, the bend corrosion-usually elbow wall thinning, partial pits and pitting. For elbow internal corrosion causes and ways need to follow a certain way and principle, can now more widely used at home and abroad elbow corrosion detection method is leakage flux and ultrasonic detection. Ultrasonic ultrasonic inspection method is the use of ultrasonic pulse reflection principle to measure the wall thickness after etching.
Method leakage flux detected by the magnetic flux leakage of the basic principle is based on the high-permeability properties of the ferromagnetic material, the magnetic permeability of the elbow corrosion defects much less than the permeability of the elbow, the elbow magnetizing the magnetic field is applied, when the bend of the non-defective, the magnetic field lines substantially through the pipe, then the magnetic field lines uniformly distributed; elbow when internal defects, the magnetic field lines are curved, and a portion of the surface of the magnetic field lines leaking out of the pipe. Detecting the escaping surface leakage magnetic flux bends, can determine whether a defect exists. One of the more common is the alloy elbow, alloy elbow resistance of air, steam, water and other corrosive medium and weak acid, alkali, salt and other chemical etching medium corrosion of steel. Practical applications, often the weak corrosion resistance as stainless steel corrosion medium alloy elbow, while the resistance to chemical corrosion of steel known as acid-resistant steel. Due to the difference in chemical composition, the former does not necessarily resistant to chemical corrosion, while the latter generally have a stainless steel. Stainless steel alloy elbow does not produce corrosion, pitting, corrosion or wear. One of the highest strength material with metal or stainless steel construction materials. Because stainless steel has excellent corrosion resistance, so it can maintain a permanent structural components of the engineering design integrity. Bend test method alloy corrosion leakage flux method. Fundamentals flux leakage detection method is based on the high-permeability properties of the ferromagnetic material, the magnetic permeability of the corrosion defect elbow bend is much less than permeability head bends under the applied magnetic field is magnetized when the elbow is no defect, the magnetic field lines substantially through the pipe, then the magnetic field lines uniformly distributed; elbow when internal defects, the magnetic field lines are curved, and a portion of the surface of the magnetic field lines leaking out of the pipe. Detecting the escaping surface leakage magnetic flux bends, can determine whether a defect exists.
When the probe detects a vertical inner wall of the elbow to transmit ultrasonic pulses, the first probe is received by the inner wall surface of the reflected pulse, and then receives the reflected ultrasonic probe pulse will come from the outer wall surface, the inner surface of the pulse and the reflected pulse of spacing distance between the reflecting wall thickness. Elbow in accordance with the actual needs of the detection of the actual situation and instructions, in accordance with the ultrasonic inspection method can detect a good way.
