Design And Research On A New Type Defect Detector For Wire Ropes

Steel wire ropes as an important part of traction and load are widely used in the coal, metallurgy, and marine industry. The condition of them is related to the safety of the equipment directly. It will be the terrible result once the accident happened. At present, the detection methods and systems for steel wire ropes have some disadvantages. High magnetic detection has not enough testing accuracy, and is largely affected by the detecting speed. The structure of the detector is complicated, and the magnetization and defect detection are not synchronized; many detectors use singlechip as control system, which has lower performance. Therefore, based on the technology of weak magnetic detection, a new defect detector for wire ropes was designed in this paper. The main contents and results of research are as follows:Firstly, non-destructive weak magnetic testing technology was proposed through analyzing the structure of wire ropes and non-destructive testing principle. The magnetization module and sensor were designed. The weak magnetic sensor was selected as detection sensor and the vector synthesis of magnetic field was used to detect.Secondly, based on the modular design method, the overall structure of the detector was analyzed and divided into four function modules. The model of each function part was established and assembled into a whole module by means of Pro/E software. The weak magnetic magnetization and defect detection are designed as a whole, breaking the traditional two-step testing situation. Then, the finite element dynamic analysis was used to analyze the guide rollers to ensure the product structure design is reliable.Next, according to the need of the on-line detection, tthe detection system was designed based on the ARM7 microprocessor. The key part of the system uses LPC2368 chip of the Philips ARM7 TDMI. Hardwares of the system include signal conditioning, A / D converter, keyboard input, liquid crystal display and USB interface. The system can carry on real-time detection alone using communication interface, and also can connect with the PC to analyze the testing results.At last, lots of experiments have been done to test the system and structure of the defect detector for wire ropes.Experiment results show that the new type defect detector can detect different kinds of defaults of wire ropes by means of weak magnetic detecting technology. The detecting results are in accordance with the actual damage of wire ropes basically. The studys provide a useful reference for the application of weak magnetic detecting in other relative fields.