Study On The Quality Improvement Of Humidifier Of S Company

Established on 1998,S company is a production enterprise with the qualification of import and export.S company began to design,produce and export humidifiers seventeen-years ago.The humidifiers made by S company win a great reputation among its foreign customers.However,some kinds of quality problems remain.During the recently years,the manufacture scale of S company is still growing and the cooperation with foreign famous enterprise is extending,these problems do need to be settled for the further improvement of humidifier quality.At the beginning,the paper collects and analyses the quality problems arose during the year 2012 to 2014 by using statistical survey method and Pareto Chart,and it is found that the warpage of plastic part and water-leakage of reservoir are the main problems.According to the present actual conditions of S company,PDCA cycle is choosen as the improvement method,beginning with the analysis of the two main problems,finding out the main factors,then making a plan and executing the plan,checking the results and finally adding all the revised data to the technical files in order to achieve its standardization.To solve the plastic part warpage problem,Moldflow software is introduced into the improvement.With the help of the software the gate location is optimized,the coolant circuit is rectified,the deformation degree and the specific deformation areas are more clarified,which contribute a lot to the further improvement.The paper also optimizes four main parameters of the molding process based on the present ones by the means of orthogonal test and numerical simulation tool.The optimized parameters have already been used in the production.In order to enhance the sealing performance of the reservoir,a full study on the material,shape and dimension of sealing ring and the height of reservoir lip is made.Their improving plans are suggested later.Two sets of work tools are made for shortening the reservoir lip dressing time and sealing performance inspection time.During the improvement of sealing ring,a better solution based on the stress and deformation analysis result of Ansys software is put forward,which makes the sealing performance increased once more.Due to the lack of advanced analyzing method or inspection tools,the warpage problem and the water-leakage problem cannot be solved till this time.After the improvement,the assembly process is more smooth,the labor efficiency is highlyenhanced.But there are still some items left to be improved,which will be considered in the PDCA cycles afterwards.