Abstract:
This thesis is prepared and written about information system for a company, which business is to sell imported control valve and its parts to petrochemical chemical industry. This thesis covers how to prepare the preventive maintenance and part management for the purpose of higher efficiency of control valve's maintenance schedule and parts sales. Preventive maintenance can be planned by taking into consideration historic data of control valve's usage, appropriate maintenance frequency, which is recommended by suppliers, priority and operation frequency of the production process, operating efficiency and also the performance record kept by maintenance section the plant. The importance of control valve can be critically classified by method of ABC control. There are 4 criteria, which are importance level, location, process condition and impact on product quality. Applying the criteria, discussion with those concerned and by their deduction, the planning of the preventive maintenance of the control valves can be separate into categories, which relies on requirement level of maintenance. In this thesis, classification will be separated into group of A, B1, B2, B3 and C, respectively, including the maintenance of each, In general, control valve shall be inspected and tested every specific duration, such as quarterly, semi-annually, annually or at any specific shutdown period. Preventive maintenance plan shall be practiced by 4 actions, which are Inspection, Test and Calibration, Clean and Check Inside Value, and Overhaul of the Valve. The parts need to be changed for any cases, while control valve is at the time of maintenance, those overhead parts should be compatible and also should be recommended by makers. In this thesis, there are list of parts which should be normally kept in warehouse for any emergency maintenance following the method of interchangeability technique, and prepare the maintenance report to record in the maintenance section. Part management of the control valve will be organized from the database and necessary part items for each type of valves which are very important for operation will be prepared. It will be done as per maintenance manual and serial no., which must be prepared by experienced technicians. Part sale will be offered to customer 2 months prior to next maintenance. This is the extension of sales process, consisting of such stages as quotation preparation, waiting for confirmation of purchase order, ordering to makers for production and its lead time for delivery. Practical program shall be access for making database. Delphi is main program and it will be a the interface to the users. The program will run for the process of part management, which included be the calculation of price, cut and reservation of products, issuing quotation, issuing production order and etc. Overall, we were able to design and make information system for preventive maintenance plan of the control valves as well as to manage the necessary parts for appropriate maintenance plan, which can reduce duration of the processes to getting the parts. The parts inventory of the sales company will be managed by the just in time method and customers will be confident enough about parts arrival in time.