Measurement Mechanism And Method Of Tire Multilayer Film Thickness Based On Terahertz Technology

As an important part of tire,the quality of tire film affects the overall performance of tire,and indirectly affects the safety and comfort of automobile.At present,the detection of tire semi-finished parts in tire production industry at home and abroad mainly depends on X-ray and artificial eyes,which can not fully meet the needs of the development of tire industry.In recent years,great attention has been paid to terahertz technology and developed in the field of detection because of its advantages of safety and non-contact,but it has not been studied in the field of tire film detection.The quality problems such as uneven thickness of tire,uneven coating thickness of steel cord fabric,internal defect and other quality problems are common during the production process of tire film,which can affect the performance and the service life of tire.Therefore,it is necessary to check the thickness non-uniformity of multi-layer tire film.According to the quality index and precision requirement of,the mechanism and method of multi-layer tire film thickness detection based on Terahertz technology are discussed in this paper:(1)Based on the characteristics of penetration and reflection to non-ionizing media of THz wave,the mechanism and method of detecting the thickness and internal defect of multi-layer tire film are studied in this paper.A method based on the terahertz technology for measuring the thickness of multi-layer tire film was established;(2)Based on the reflection and refraction characteristics of terahertz wave,a mathematical model for measuring the thickness of multi-layer tire film was established.The experimental study and test are carried out for single-layer,two-layer,three-layer tire film and steel cord fabric.The calibration method of the thickness of multi-layer tire film detection by THz technology was established,and the test resultswere analyzed and compared with the results of caliper test.The stability and accuracy of the tire film thickness results detected by THz wave can meet the requirements;(3)The tire film with preset defects was prepared,and the terahertz imaging test was carried out by scanning,and the internal defects could be identified by this method;(4)Based on terahertz technology,the on-line and off-line testing equipment for tire film thickness was designed,the 3D model of the equipment was established,and the design and analysis of key components were described in detail;The test results show that the thickness of steel cord fabric can be measured by terahertz technique,and its accuracy and stability meet the requirements.This study provides a new and effective method for measuring the thickness uniformity of steel cord fabric and tire film.