Research On Dynamic Monitoring Method Of Wire Rope Tension Of Multi-Rope Hoist

As key pieces of equipment for coal,workers and materials transportation in coal mines,hoists play a vital role in ensuring production safety.To monitor the operation status of hoists,it is a common way to measure the tension of wire ropes at present.However,due to the harsh condition in mine shaft,wire ropes are easily subjected to longitudinal and transverse coupled vibration,making it a challenge to measure the tension with high accuracy.For this purpose,the dynamic monitoring method of wire rope tension of multi-rope hoist is researched.Firstly,the working principle of multi-rope friction hoist is introduced.The wire rope tension can be measured by converting it to the pressure acting on the sliding block in tension self-balance hanging device after comparing several existing dynamic tension measurement methods.On the basis of this method,the general scheme of the whole tension monitoring system and communication scheme between each part are designed.Secondly,a new type of pressure sensor with acoustic filtering characteristics is designed according to its installation position of the chosen method.The sensor is equipped with an oil cavity and a perforated panel.Vibrational energy can be dissipated through the fluid-structure interaction between oil and oil cavity and the reciprocating motion of oil on both sides of the perforated panel,and thus the influence of external vibration and impact on output signals of the sensor is eliminated.On the basis of this principle,specific structure of the sensor is designed,and its measurement and acoustic filtering principle are analyzed through structural simplification and equalization.In addition,to ensure the safe application of the sensor,corresponding statics simulation is also carried out.Then,in order to optimize the acoustic filtering performance of the sensor,its sound absorption characteristics under different structural parameters of oil cavity and perforated panel are researched.For the oil cavity,the sound pressure of extracted field point is selected as the research object,and the vibro-acoustic coupling response for coupling model under different oil cavity parameters is solved.For the perforated panel,the sound absorption coefficient is selected as the research object,and the sound absorption characteristics of perforated panel under different structural parameters are compared and analyzed.Finally,performance tests of the acoustic filtering sensor are accomplished.Atfirst,main static characteristics of the sensor are calibrated in the laboratory.Then,qualified sensors are installed on the tension self-balance hanging device to measure the tension of wire ropes.Compared with the data measured by oil pressure sensor and universal pressure sensor,the acoustic filtering sensor could effectively overcome the shortcomings existing in the other two methods,and its tension curves are in accord with the theoretical situation.Besides,to visually display the monitoring results and facilitate the staff to keep abreast of the operation status of the hoist,a set of tension on-line monitoring software is developed.The in-situ application results show that the whole system can achieve the wire rope tension monitoring in real-time and satisfy the requirements of coal mine.