Application Of Control Chart Technology In Dynamic Monitoring Of Double Twist Process

With the rise of intelligent manufacturing,intelligent textile industry development has entered a new period.With the fierce competition in the market,enterprises can enhance their competitiveness only by constantly improving the quality of their products.There are many links and complex processes in textile production.In order to ensure product quality,it is necessary to improve the quality control level of key processes.The quality control of double twisting process is an important part of producing qualified and high quality textile products.The use of traditional methods such as post measurement,manual statistics and estimation to control the quality of textiles can no longer meet the needs of modern textile production process.At present,the double twisting process has entered a new stage of development with intelligence.With the integration and application of information technology and Internet of things technology,double twisting production data can be collected,so that enterprises have a large number of data resources.Combined with the actual production site of double twisting in the enterprise,by excavating the value in data resources,looking for the idea of modern double twisting quality control,and studying the method of quality control of double twisting process which is suitable for modernization at the present stage,it is of great significance to improve the quality control level of double twisting process.This topic takes the double twisting workshop of High Fashion Silk(Zhejiang)Co.Ltd.as the research object to explore new ideas and methods to improve the quality control level of double twisting process and equipment condition management.The main research work and related conclusions are as follows:(1)First of all,the double twisting process is analyzed,the present situation of production data information collection and quality control in the digital double twisting workshop of High Fashion Silk(Zhejiang)Co.Ltd.is investigated,and the relevant methods of quality control are studied.On this basis,the dynamic monitoring scheme of double twisting based on spindle speed is determined,and the control chart technology is introduced into the monitoring of double twisting process.In this paper,a method of dynamic quality control and equipment condition monitoring of double twist based on control chart technology is proposed,which establishes the foundation for the global control of the research direction and idea of quality control in double twist production process.(2)On the basis of studying the relevant application theory of control chart technology in quality control,the realization path of dynamic monitoring of double twist is determined,the monitoring object is established,and two monitoring indexes of spindle speed Ntier and spindle speed CVtier are designed,the sample data acquisition scheme for double twist process is established,the data missing preprocessing method is determined,and some problems in the database design of double twist dynamic monitoring and analysis are solved.The experimental application of the dynamic twister monitoring method based on control chart technology was studied by using the production data obtained from Dali Silk(Zhejiang)Co.,Ltd.First,the production data of 25 batches of twister analysis were collected and sorted out,and the sample data of monitoring indexes were calculated.The characteristics of sample data are analyzed in detail from three aspects of variation source,independence and normality.According to the characteristics of the double twist sample data,by judging the estimation method of the control limit,it is determined that the I-MR-R three-way control chart is used to monitor the two indexes.The analytical control charts of the two monitoring indexes are established and analyzed by calculating the control limit,the stable results of the production process of the research equipment are obtained,and the transformation of the control chart is realized.Finally,the production data of 22 batches were collected and collated to carry out the subsequent application verification by using two methods of continuous verification and interval verification,which initially verified the feasibility of the method research.(3)By using the I-MR-R control chart of spindle speed Ntier and spindle speed CVtier,we can directly,quickly and dynamically judge the spindle speed and spindle speed unevenness between spindles,quantitatively judge the change and trend of the index through the fluctuation of index data,and judge whether the double twist production process is stable and whether the equipment condition is abnormal by using the relevant abnormal criteria of the control chart.From the short-term and long-term time dimensions,monitor and forecast the small range variation of spindle speed unevenness and monitor the variation of twist unevenness,so as to provide a basis for the formulation of equipment maintenance strategy,and realize the purpose of quality control of double twisting process and equipment state monitoring,improve the efficiency and level of quality control of double twist production.It is beneficial to the company’s quality management concept transformation,production control level and efficiency improvement,product quality assurance,equipment maintenance strategy formulation,data resource management and application and so on.Through the exploration and research of this subject,it is considered that it is feasible to improve the quality control level and equipment state management of double twist process by using dynamic monitoring method based on control chart technology,and the stability of double twist production process can be judged by using three-way control chart.The control chart technology to monitor the double twist production has important practical significance to improve the double twist quality control and equipment management level.