Two Ways of Manufacturing the Valve - Case Study Example

Manufacturing of Valve Body Name: Course: Date: Report As a manufacturing engineer in the Fort Vale Engineering limited in Burnley, I have been entrusted with the task of manufacturing the valve body. The following is a report of the manufacturing method of the valve including the images of the different processes of manufacturing the valve. Two ways of making the valve There are two ways of manufacturing the valve at Fort Vale Engineering. These ways include investment casting method and the CNC milling method. I shall explain what these two different strategies involve in terms of manufacturing engineering. Investment casting method According to Winker 2010, investment casting is a method that involves a lot of waxing. Investment casting is also used in the production of ferrous and non-ferrous metal parts (Winker 2010). Investment casting produces excellent surfaces finish and high dimension accuracies. The valves therefore produced in the investment casting method are fitting and need no further adjustment. In the investment casting method almost 200 alloys are used meaning that no other production method can use. The investment casting method uses the ceramics and other expandable parts it is therefore essential for the production of detailed and complex design patterns (Winker 2010). Intricate parts that are difficult to manufacture are manufactured in this process. The investment casting process begins with a pattern. The Gates and the vents are attached to the pattern to be used and eventually attached to the sprue. Many patterns attached to the sprue form what is called a casting tree. The casting tree is then dipped into slurry a process known as investment to form a hard shell. According to Winker 2010, the investment process is followed by the burn out process in the melting of the patterns leading to the cavity in the process. A preheated metal alloy is then poured into the investment leading to the shells breaking after cooling. At this point therefore the metal parts are cut from the tree and then the gates and the vents are broken from the slurry. CNC Milling CNC milling falls under the category of pattern less valve making (Pastircak, Urgela and Krivos 2012). CNC means computer numerically controlled milling. CNC has come into being with the rise in the technological process of milling where the machines are programmed into what kind of patterns are to be produced. The CNC milling involves the mixing of mixtures such as those containing synthetic resins (Pastircak, Urgela and Krivos 2012). The mixture is hardened by blowing carbon dioxide through it. The dimensions used for the casting are fed in the inflow system that is used for casing. The core is produced, saved in the step process and then opened using the Cut 3d program. The cut 3d has got several options of what faces of the core to mirror, the faces to be rotated and the areas to be set according to the various measurements standard such as the inches or the metrics. Several tool paths are created and saved in the G-code. The G-code is responsible for the roughing up of the process and eventually finishing of the process. A (b) The choice of investment casting method The investment casting method according to me is the best choice of the manufacturing of the valves. The investment casting method is a very quality way of producing valves that are unique and the specificity in production is seen in the involvement of the patterns in the production process. The pattern that has been made in the investment casting method can easily be modified to harden the shell of the valve so as to prevent cracking of the valve (Winker 2010). The hardening of the valve distinguishes it from the other processes of making valves such as the CNC milling method. Still in the design phase, the internal patterns size can easily be modified so as to create room that prevents the expansion phases of the amount of expansion forces. The benefit of the investment casting method in the manufacturing of valves is the precision that the investment casting method of manufacturing comes with. The shapes being cats in this process are almost neat thus improving the versatility of the process. The dimensions that are used in the manufacture of items are precise and therefore making it efficient for the production of automobiles and even jets. Since the shapes are made in a single molding there is uniformity in the process of production. In the economical view, Investment casting method saves a lot in the production process. Only a single machine is required in the process of manufacturing as compared to other processes such as the CNC machine milling process. The Investment casting method is also cost efficient while dealing with lesser quantities of products. The prototyping method also enables the production of items for test as well. In conclusion therefore Investment casting method is clearly preferred to other manufacturing methods. Process plan with figures Mondal 2004, lists out several processes that are involved in the investment casting method. The process begins with the fabrication of the wax into the pattern that is designed to appear in the last cast. The investment wax is basically injected to the metal wax injection die and thus this process is referred as injection molding. This is indicated in figure 1.1 As soon as a pattern is formed, the wax is attached to the stick referred to as a sprue so that they may together form a clustering pattern referred to as an assembly of the various patterns. This is illustrated in figure 1.2 The pattern is additionally dipped into the slurry and then covered with a sand stunnco for drying. This is a process known as moulding. It is shown in figure 1.3 The next process is referred to as dewaxing (Cotton 2013). This is where the stucco-covered pattern is placed in a steam auto clave to remove the wax. A furnace is used to burn out any remaining wax. Figure 1.4 The mold left after dewaxing is heated to a specific temperature and then it is filled with metal casting a process known as metal casting (Cotton 2013). Figure 1.5 After casting has cooled off, the molding is chipped from the casting a process known as Knock out. Figure1.6 The gates and the runners are cast off from the molding a process referred to as cutting off. Figure 1.7 The last process is where the casting is finished and is ready for sale or use. Figure 1.8 Source of images: Solid work models Costing of the manufacturing process The first item of costing is labour. There is need for a high number of skilled personnel to operate the machinery to handle the technical issues as well as the administrative issues that are found in a company. In Burnley the costing of labour can be approximated to be around 30-40 % of the total cost of production. This is mainly because labour is essential for the running of the business. The total cost shall be $AUD 2.0 M for the hiring of quality labour in the market. The cost of manufacturing may be $5000- $25000. This includes the cost of the tools that are used in the manufacturing process as well as the personnel involved in the process. There are various materials that are used in the production process. The unit cost per object produced in Burnley is $ 300. This is economical compared to the total costs of the items. The mark up and the overhead costs of manufacturing stand at $ 1.2 M and 1. 0 M respectively. References Cotton John 2013, Investment Casting: An Investment in Quality. Retrieved from http://www.mandplabs.com/interface/uploads/files/whitepapers/investment-casting-white-paper.pdf NATIONAL CONFERENCE ON INVESTMENT CASTING, & MONDAL, B. (2004). Proceedings of the National Conference on Investment Casting: NCIC 2003. New Delhi, Allied Publishers. Pastircak, R ,Urgela, D, and Krivos,E 2012, Production of Castings by Pattern less Method. Retrieved from http://www.afe.polsl.pl/index.php/en/3512/production-of-castings-by-patternless-process.pdf Winker, Robert 2010, Investment Casting Retrieved from http://www.cimetrixsolutions.com/downloads/AG-InvestmentCasting.pdf Read More