Development Of Quality Inspection System For External Threads Of LPG Cylinder Valves

Liquefied gas cylinders are normal tools which are closely related to our lives.Recently,liquefied gas cylinder explosion accidents have attracted people's attention.The occurrence of these accidents has seriously jeopardized people's property and life safety.Analysis of the causes of accidents has become the focus of our attention.Apart from the aging of connecting pipes and the improper operation of users,there is one of the most important factors,namely,sealing.Poor sex caused leakage of liquefied petroleum gas.We usually use a threaded connection to connect with other components,and the quality of the external thread directly affects the tightness of the liquefied gas cylinder.Therefore,we put forward higher requirements on the quality of the external threads of the liquefied gas cylinder valves.There are many kinds of quality inspection methods for the external thread of the valve,including the traditional method of detecting the external thread parameters by manual means,and the non-contact thread detection of the three-needle method and the image method.These methods are all developed with the times.And the update is improved,they all have their own advantages and disadvantages.Manual detection is greatly affected by human factors,and the efficiency is not high.The accuracy of the three-needle method is suitable for batch industrial operation.The detection method of image method is simple and easy to operate,easy to mass production,but easily interfered by external factors.To bring a large detection error.All of the above methods are not well adapted to the needs of the rapid development of today's industrial technology,so in this topic we have proposed a new detection system,a three-eye vision system combined with image processing technology to achieve external threads for liquefied gas cylinder valves The detection method is adopted by the layout design of the trinocular vision detection system,and then the image processing is used to measure the parameters of the external thread(thread diameter,pitch,tooth angle,etc.),and the optimal algorithm is selected to improve the detection.Accuracy,and finally compare with the standard parameters to achieve the judgment of the quality of the external thread quality,in order to achieve real-time efficient and can be tested in batches for industrial automation testing requirements.