Development of Application Software for Stock Material Selection for Manufacturing of Shafts

Transcription

1 Development of Application Software for Stock Material Selection for Manufacturing of Shafts Oduola. M. O., Akinluwade, K. J., Immanuel, T., Efozia, N. F., Musa, D. I., *Adetunji, A. R. Department of Engineering, Prototype Engineering Development Institute (PEDI) [National Agency for Science and Engineering Infrastructure, NASENI] *Department of Materials Science and Engineering Obafemi Awolowo University, Ile-Ife Corresponding: ABSTRACT Proper production planning ensures judicious utilization of manufacturing resources. It is understandable that the administrative rigor of planning appreciates intervention of programmable software to ease the stress and improve efficiency. The present study developed application software to predict and select stock material of minimum dimension ahead of turning of shafts of a specified finished dimension. Microsoft s Visual Studio Integrated Development Environment (IDE) was utilized to develop the multi-module software application. Finished dimension data supplied (diameter and Length) are the operands utilized at arriving at required raw dimension data. The keyed in data (diameter and length) are the program variables used by the application at run time. Decision constructs based on standard material sizes (constants) was keyed into the application for raw dimension diameter data, ranging from and the Standard sizes are in 3 categories. The specified conditions were programmed into the application to arrive at and display raw length data output. The software was tested based on the stated categories and from the results displayed the application software did resolve to a great extend the challenge imposed on production engineers in the area of production. Keywords: Micro-processor, computers, IDE, Finished Dimension, Raw Dimension, Algorithm, and Stock-materials, production, planning, software, efficiency, stock materials, resources, raw materials, materials selection, cost INTRODUCTION To meet the rigorous demands of product designers and development engineers, prototyping materials are the critical link to product design validation and product development process efficiency. Successful product developers understand the value of time. Time-to-market can be dramatically reduced if prototype-to-production bridge materials mirror production material specifications [1]. An important part of the production process is the raw materials used to produce goods. Finding the right type of production materials helps companies to produce competitive goods for consumers. Using the right type of materials ensures that companies earn the highest profitability with the least amount of product defects or consumer complaints [2]. Material selection is a step in the process of designing any physical object. In the context of product design, the main goal of material selection is to minimize cost while meeting product performance goals [3]. Systematic selection of the best material for a given application begins with properties and costs of candidate materials. For example, a thermal blanket must have poor thermal conductivity in order to minimize heat transfer for a given temperature difference. Cost of materials plays a very significant role in their selection. The most straightforward way to weight cost against properties is to develop a monetary metric for properties of parts [4]. Production planning processes are used by manufacturing companies and other types of organizations to make a logical plan for work performed by computers, machines and humans. This specialty usually falls to industrial engineers, but managers in manufacturing also make decisions that affect the production planning process [5]. The basic purpose of production planning and control is to get maximum output out of the given resources of men, 12

2 machines and plant. This can be achieved through better utilization of these resources and by getting a higher rate of production [6]. According to Tiwari [6], the quality, size and composition of materials also have their own effect on the rate of production and output. The goal of this paper is to demonstrate the roles that a simple computer software application can play in simplifying the material planning function in the production of materials. The application simplifies the task of raw materials selection. This helps in eliminating waste, which in turn leads to decrease in production costs. Manufacturing process management is a collection of technologies and methods used to define how products are to be manufactured [6]. Manufacturing processes are the steps through which raw materials are transformed into a final product. The manufacturing process begins with the creation of the materials from which the design is made. These materials are then modified through manufacturing processes to become the required part. Manufacturing processes can include treating (such as heat treating or coating), machining, or reshaping the material. The manufacturing process also includes tests and checks for quality assurance during or after the manufacturing, and planning the production process prior to manufacturing [7]. The scientific contribution of the paper in view of the fact that materials management is concerned with; (1)the planning and programming of materials and equipment, (2)market research for purchase, (3)procurement of materials, packaging, storage and inventory control, (4)transportation of materials, salvage, materials handling, disposal of scrap and surplus [8] and (5)it helps to reduce the quantity of waste from production materials. The structure of this paper is as follows: section 2 describes the proposed software, testing and system configuration, section 3 discusses results obtained from testing of the software and section 4 draws conclusion. 2.0 METHODOLOGY Description 2.1 SOFTWARE DESCRIPTION AND SYSTEM CONFIGURATION It s a software application that assists production engineers in easily deducing or realizing the raw material dimensions (comprising of diameter and length) required for the production of shafts. It simplifies the task of figuring out the quantity of raw materials required to produce a finished product. The software application calculates and produces the required raw materials dimensions (diameter and length) based on the finished materials dimensions (length and diameter) key in by the application user. The required output is deduced based on standard material sizes programmed into the application. The standard material sizes were detailed by users during the requirement gathering and analysis phase of the development process. Minimum material standard size is 5 Ø, while maximum material standard size is 310 Ø. Annotated diagram of typical shaft For a turning process where the required output is a finished length FL and finished diameter FD as shown in Figure 1. 13

3 Fig 1. Diagram of Finished Shaft Dimension The stock material for turning must have a minimum initial length Li and initial diameter Di as shown in Figure 2. Fig 2. Diagram of Minimum stock material It follows that, the required stock must have a dimension required diameter RD by required length RL as shown in Figure 3. Tools and Programming Language used Fig 3. Diagram of the required stock Microsoft s Visual Studio Integrated development environment (IDE) was utilized to develop the software application. Visual Basic.NET was the programming language used in the IDE. The IDE was used because it contains tools to build robust applications for windows quickly and efficiently. Forms were used as user interfaces for the application. The forms have controls such as text boxes, buttons, labels etc. VB Program code was added into button controls to process user clicks and produce required output. Modules The software application is comprised of the following modules Launch the application module 14

4 Capture user input module Process captured user input module Display results module Exit application module Stock material selection software Launch Application Exit Application Capture Input Process captured input Display result/output Figure 4: System modules diagram 2.2 System Requirements Hardware Requirements Pentium 3 and above 256 RAM and above Minimum screen resolution is 800 x 600 pixels Software Requirements Microsoft Windows XP, Vista operating system and above Software precautions Limit cap of input digits for both finished diameter and length is 300.5, while maximum output displayed is 310 and 315 for raw diameter and length respectively. The calculation is based on material standard sizes spelt out by users (during the requirement analysis and information gathering phases). Input can consist of either decimal point numbers (e.g. 45.6, etc) or whole numbers (46) but output is displayed in whole integer numbers (e.g.50,105,115 etc) as a result of the standard material sizes programmed into the application. 2.3 SOFTWARE/MODEL BUILDING Keyed in finished dimension data (diameter and Length) are the operands utilized at arriving at required raw dimension data. The keyed in data (diameter and length) are the program variables used by the application at run time. For example the system will output the following raw dimension information for the following entries: Keyed in material dimensions (finished dimension) - 15

5 Ø62.5 x 80lg and Ø x 82.15lg. Output results(raw dimension) - Ø65 and 85lg and Ø75 x 87lg respectively. Note: Ø implies Diameter and lg implies Length. Keyed in entries for finished diameter are compared against standard material values programmed into the application. These standard values are the constants of the application, stored into an array container. Program constructs were used to compare keyed in values with the constants to determine the appropriate raw diameter material value to be displayed. Conditional logic was programmed into the application to arrive at required raw dimension length information. The standard material sizes (constants) keyed into the application for raw dimension diameter data range from Standard sizes are in 3 categories: (difference between standard material sizes in this range is 5 e.g. 5, 10, 15, 20 etc) 2. From (difference between standard material sizes is 10 e.g. 105, 115, 125 etc) 3. From (difference between standard material sizes is 15 e.g. 220, 235, 250 etc) Raw length data is derived based on the following: 1. Keyed in finished length data plus 5 for materials within raw diameter range Keyed in finished length data plus 10 for materials within raw diameter range Keyed in finished length data plus 15 for materials within raw diameter range Decision constructs based on the specified conditions above were programmed into the application to arrive at and display raw length data output. 2.4 GRAPHICAL USER INTERFACE DEVELOPMENT The application is named Stock Materials selection software. The user interacts with the software through a GUI. The GUI components include buttons, input/display fields, icons etc. Software operations are invoked by actions performed on GUI components using input devices such as the keyboard and mouse. The GUI was developed using the Visual basic.net visual studio IDE. The IDE s palette of developer objects (controls) were used for the GUI components. Features of the GUI include the following: The startup graphical user interface This is the interface that is displayed when the application is launched. The interface has two buttons Start Application and Exit Application. Step1 Start Application button takes the user to the interface containing fields to capture input/entries (finished diameter and length) that the application will use to the produce raw dimension (diameter and length) information required amongst others. Step2 The Exit Application button closes the application. 16

6 Figure 5: Screen capture of the startup user interface The Data capturing, processing and display graphical user interface This is the interface that is used to capture finished dimension data (diameter and length) needed to arrive at the required raw dimension data (diameter and length). Captured data is processed and result is displayed in another part of this interface. This interface comprise of the following sections: 1. Finished Dimension Section: This part of the GUI contains entry fields to enable user key in required data (diameter and length) needed to produce displayed raw dimension data. 2. Raw Dimension Section: This part of the GUI has display fields that are used to output and present calculated data. The calculated data is displayed in the diameter and length fields respectively. The Data capturing, processing and display user interface also has buttons (Calculate, Clear and Exit). Clicks on the buttons perform the following operations: 1. Calculate button: A button click calculates required raw dimension data (diameter and length) which is displayed in their respective fields on the GUI 2. Clear button: A button click clears entries from text boxes on the GUI 3. Exit button: A button click closes the application The user interface also has icons such as minimize and exit. The former causes the GUI to minimize thus placing it at the windows task bar while the latter closes the application. 17

7 Figure 6: Screen capture of the Data capturing, processing and display user interface Despite the potential usefulness and intuitiveness of the GUI, limitations identified include its inability to present required information in tabular format. This feature makes provision for the presentation/display of multiple bits of data (output results) at a time. Another limitation includes GUI s inability to support materials that have dimensions that contain thickness (in addition to diameter and length). The application currently supports dimensions in diameter and length only. These limitations require modifications to the implementation. The current GUI implementation however, provides a reasonable foundation upon which further improvements can be based. Despite these limitations the GUI in its current format provides a useful and intuitive interface to assist users in easily calculating the raw material (diameter and length) required from finished material dimensions supplied for the production of shafts. 2.5 SOFTWARE TESTING AND OPERATION Testing was carried out to assess the application s response to null or incomplete and invalid inputs as well as to valid data inputs. With the testing below, the goal of the computer-aided system for material selection to aid production effectiveness was achieved. The following table contains a set of test data used. Step1: Inputs Finished Diameter data Finished length data 25 Ø 70lg 34 Ø 100lg 50 Ø 110lg 56 Ø 35lg 62.5 Ø 80lg 118 Ø 48lg 200 Ø 60lg 228 Ø 115lg 300 Ø 295lg 305 Ø 55lg 18

8 Output data for the above set of test data is presented in the next table below. Step2: Outputs Finished Diameter data Finished length data 30 Ø 75lg 35 Ø 105lg 55 Ø 120lg 60 Ø 40lg 65 Ø 85lg 125 Ø 53lg 205 Ø 65lg 235 Ø 125lg 310 Ø 310lg 310 Ø 60lg Figure 7: GUI showing a typical input data and output results 2.6 ALGORITHM OF PROBLEM SOLVING The ordered set of instructions that the software application uses for problem solving is summarized as follows: 1. Accept user input (Finished diameter and Finished length) 2. Validate user input 3. Calculate Input 4. Display result (Raw diameter and Raw length) Figure 8 below is a diagrammatic representation of the algorithm. 19

9 Start Read inputs (Finished Ø & Finished lg) Flag error Validate input s (Finished Ø & Finished lg) False Is input valid? True Calculate inputs to get results Display Result (Raw Ø) Display Result (Raw lg) Stop Figure 8: Diagrammatic representation of the algorithm 2.7 SOFTWARE VALIDATION The software was validated to ensure that it complies with user needs and functional requirements. A set of test data and scenarios were utilized to determine the correctness of final software product. They include the following: Step1: Test Input Finished Diameter data field Finished length data field 25 Ø 70lg 34 Ø 100lg Null entry 110lg 56 Ø Null entry 62.5 Ø 80lg a Ø 60lg 20

10 300 Ø 295lg 55 Ø Tlg 305 Ø 55lg The following table presents output from above test data set and scenarios. Step2: Test Output Raw Diameter data field Raw length data field 30 Ø 75lg 35 Ø 105lg Error flagged to enter finished Ø data 110lg 56 Ø Error flagged to enter finished lg data 65 Ø 85lg Error flagged to indicate that system accepts numeric 60lg values only Error flagged to enter finished Ø data Error flagged to enter finished lg data 55 Ø Error flagged to indicate that system accepts numeric values only 310 Ø 60lg Output realized from utilized test data and scenarios complied with expected results. The software is expected to calculate raw material dimensions (diameter and length) based on finished dimension inputs. Scenarios with invalid or null inputs were expected to flag appropriate errors to notify the user. Valid inputs calculated the expected results based on system requirement specifications DISCUSSION The result from the validation of the software has shown that the application is very simple to use and capable of meeting users need i.e. determining stock material selection for manufacturing of shafts. This has simplified a part of material planning function. The import of this is that raw material size selection, which hitherto had been an engineering task, could be treated as administrative function. The software, apart from simplifying the task of raw material selection, will also ensure elimination of waste. This, in turn, will result in decrease in the cost of production of component parts, particularly for shafts. A few Error flagged indicated in both the Finished Diameter and Finished Length fields as output only go to show that those input test data i.e. T lg, a Ø, Null Entry which resulted into Error output were invalid. This was done deliberately to prove that the application accepts numeric value only. This also serves as additional support to the validity of the application software as a reliable tool in raw stock material determination. To meet the challenges imposed on production engineers in the area of cost of production, it is desirable for him to have thorough knowledge of material selection and sizing in order to keep the production process competitive. Since computers are finding more and more usage in production processes, production engineers will find this application software very useful, especially in handling of vast amount of data needed to utilize raw information such as determining total raw material requirement for a particular product. Computer-aided stock material selection, the basis of this work, is an obvious choice for large industrial houses because of advantages offered by the application software. 21

11 Needless to say, present day manufacturing demands high degree of computer-aids, from design and selection of materials to final inspection of products. Based on this, manufacturing engineers are expected to have good knowledge of computer and micro-processor systems. 4.0 CONCLUSION The application was developed specifically to assist users in their roles of stock material selection in production planning process for the manufacturing of shafts. The software doesn t just aid in product design, it is also an important part of supply chain management. It allows manufacturers to find suppliers that can provide materials that meet their requirements. A brief literature was introduced in the introductory section, in the rest of the sections we discussed shafts, the software, the various task that each modules in the application software performed such as the capturing of input data. The required system configuration, testing and validation steps were also performed and finally results was discussed and conclusion drawn. Overall the software helps manufacturers maintain a competitive advantage by reducing development and certification costs as well as turnaround time. REFERENCES 1) 2) 3) George E. Dieter (1997). "Overview of the Materials Selection Process", ASM Handbook Volume 20: Materials Selection and Design 4) Ashby, Michael F. (2005). Materials Selection in Mechanical Design. USA: Elsevier Ltd. p ISBN ) 6) Tiwari, R. A. (1971). Production Planning and Control. Management Guide 9, National Productivity Council, Productivity House, Lodi Road, New Delhi, India. 7) Machover, Carl ( ). "18". The CAD/CAM Handbook. Beverly Beckert. McGraw-Hill Companies. p ISBN ) Banga, T. R. and Sharma, S. C. (1984). Industrial Organization and Engineering Economics. 12 th Edition, Khanna Publishers Delhi, India. 9) 10) Microsoft Visual Basic 2008 Step by Step by Michael Halvorson Published by Microsoft press (Copyright Michael Halvorson 2008) 22