Manufacturing Processes and Techniques - Assignment Example

AIR MOTOR MANUFACTURING PROCESSES By: Course: Professor: University: City: Date: Section 1 Manufacturing processes and Techniques i) Bunch Fitting: Base, Upright , pipes Fitting in manufacturing processes involves the use of measuring tools, marking out tools, hand tools, drilling tools and reamer and threading tools. These tools are all used together in order to come up with fine fitting spaces and to fit the required parts[Sch2]. Measuring tools that can be used for this process include vernier calipers, calipers, vernier height gauge, micrometer screw gauge, dial indicators and a combination set. Marking out tools include: scribers, engineer’s squares, spring dividers, surface plate, angle plates and vee blocks. Hand tools available include bench vice, files, file cards, hack saw, and hammer. There are two types of reamers available for this process: the hand reamer and the machine reamer[Sch2]. In the manufacture of the air motor, the above stated tools are to be used to aid in the fitting of the base, upright and the pipes. The necessary bit is to have the necessary measurements in place, then to work towards coming up with the integration of these parts by defining where the fitting will occur. i) The measuring tools are used to do the measurements on the parts. There should be some standard measures that will match up in order to come up with a precise fit. ii) Marking tools then aid in having the marking out of the measured areas in a way that the manufacturer will not have to struggle with noticing the measurements. iii) The drilling phase comes next. The twist drill can be used for this phase. iv) Manufacturers can also consider using reamers in order to: control the diameter of the created hole, to make improvements on the finish of the internal surface and the roundness of the hole. ii) Sheet metal/Press Brake: Mount of air motor Materials used for the manufacture of sheet metal In the manufacture of sheet metals, manufacturers roll large quantities of the available materials into sheets having differing thickness and then proceed to coat them with protective materials. The commonly used protective materials include zinc, tin and black oxide. The protective coating is used for the purpose of preventing corrosion hence giving the steel a longer life[Sch4]. Black iron sheet This material is used in the case where painting is necessary. A thin oxide layer is used to prevent the rusting of the sheet. Galvanized steel sheet These consist of steel sheets that have a zinc coating. The spangled appearance is the basic look that sets apart these sheets. Zinc offers good sacrificial protection based on the fact that it is highly resistant[Sch4]. Galvanized sheets that are of high quality can withstand bending and straightening for a number of times. This may however not be the case when welding or grinding is involved as the zinc gets damaged. This disqualifies galvanized sheets in the case where welding joints are to be used. Galvanized are readily available since they are the least expensive among sheet metals. Aluminum sheets These sheets are best recognized by their lightness and whitish appearance. They are preferred due to these two particular properties including the fact that they are highly resistant to corrosion[Sch4]. Stainless steel sheet These sheets have an untarnished appearance on the surface. The main advantage of these sheets is that they are resistance to corrosion. It is possible to weld and cut them without causing them to lose the corrosion resistance property. Nickel and chromium are the two main elements added to steel for alloying. The main classifications of stainless steel based on alloy content are: 200 series, 300 series, and 400 series[Sch4]. The Manufacturing process The processes used in manufacturing sheet metals are classified into two categories based on material deformation and material removal. The deformation process is a stage where the bending or the stretching of sheet metal parts into 3-Dimensional shapes occurs. On the other hand, material removal gives rise to complex 2-Dimensional shapes[Sch4]. Water jet is one of the basic manufacturing processes for the sheet metal without shearing. The process involves application of highly pressurized water (2000 ft. /sec) stream on a metal sheet. The water should have abrasive particles that enhance the cutting of the materials. In order to come up with more accurate cuts, the water jet machine is usually controlled by a computer. For the manufacture of the mounts of the air motor, this process is more applicable since the cuts have a width of 0.002 to 0.06 inches and since heat is not applied in the process, there is no heat distortion issue to be concerned about. iii) Lathe work/CNC: flywheel, crankshafts, cylinder, head, piston, connecting rod, bush, bearing housing, cylinder pivot, knuded nut. CNC stands for Computer Numerical Control. CNC machines work according to the already programmed instructions that are fed into the machine’s controller unit. The controller unit of the CNC machine is basically a microcomputer. There is a small board on the machine on which its user can feed the machine with instructions[Har15]. The microcomputer’s memory stores the machine’s programs and programmers are at the liberty to edit pre-existing codes or to create new programs if necessary. Fortunately enough, one program can serve in the generation of different parts hence repetition of the coding can be avoided[Har15]. How the machine works The CNC machine has the microcomputer o through which instructions are fed in order to have the cutting occur as requires. Once the instructions have been fed, the cutting process is set to begin. The operation of the CNC Machine can be compared to the operation of a robot which basically follows the programed instructions[Har15]. Lathe work Lathe machines are well suited to run on CNC machines. In the manufacture of the air motor, the pieces requiring lathe work for their formation can be created by having the CNC machines. The flywheel, crankshafts, cylinder, head, piston, connecting rod, bush, bearing housing, cylinder pivot and knuded nuts are the parts of the air motor for which the use of this machine is best suited. The required dimensions represented on a code are fed into the CNC machine and the cutting process occurs to have the above named parts as the final products[Har15]. v) Milling/CNC: Connecting rod, crank web Milling machines can also run on CNC Machines. Specific codes are created in order to come have the connecting rod and crank web of the air motor created. The CNC machines basically remove parts of the metal in order to come up with the required shape[Sch1]. The milling process on a CNC Machine Since the CNC machine is quite automated, the operator’s task is to have the instructions fed into microcomputer then load the materials for use in the CNC Machine[Har15]. The milling process automatically occurs to produce the connecting rod and crank web required[Sch1]. vi) Laser/Water jet Cutting : On Laser Mount of air motor Laser cutting involves the cutting of a precise design from a material by having a CAD file guide the process. The commonly used lasers in the industry are Nd, Nd-YAG and CO2 lasers. CO2 Machines are the commonly used machines. Manufacturers use a laser beam to cut through materials by burning, melting or vaporizing the material in use. The manufacturing process A fiber optic laser is used to make cuts through metals. A laser is usually generated at a power source then directed towards the cutting head of the cutter, where there are gases being introduced and consequently the cutting process occurs[Las13]. vii) Water jet: Upright and base. Water jet cutting as a technique utilizes an extremely thin stream of highly pressured (2000-6000 bar) water running at fast speeds to cut through some material[Ino10]. This technique could be related to the water erosion process observed in nature only that there is acceleration and concentration of water. Machines called pure water jet machines make use of water and are used to cut soft materials. On the other hand, there are machines known as abrasive water jet machines which are used for the cutting of the harder materials. Abrasive water jet machines make use of abrasive material that is added to water to make the cutting through the hard material possible[Ino10]. The process is usually noisy hence manufacturers using this process have to develop water jets while the heads of the water jet machines are immersed in water tables. Water jet cutting is a characterized by: i) The use of a stream of abrasive particles, such as granite, that are under high velocity and are suspended in water that is under high pressure ii) It is used the machining of a large variety of materials. The materials rang e from the very delicate ones to the hard materials iii) Heat damage is not experienced on the work surface in use. iv) Sintered boride is the major material used in the making of water jet material nozzles v) There is the production of tapers that are less than a degree for most cuts. These tapers are easily eliminated by having the cutting process slowed down vi) The distance of the nozzles is a factor that affects the rate and quality of material removed as well as the kerf size. The water jet cutting process There is a cutter to which the manufacturers connect to the source of highly pressured water. Water is consequently let out of the nozzle, causing a cut on the material in use by having the constant jet of water sprayed on it. Abrasives such as bauxite and granite are added to the highly pressured water to aid in the process[Ino10][Sch]. viii) Strip and Build: Assembly air motor The assembly of the air motor is based on the use of the procedures discussed under the bunch fitting. It revolves around carrying out measurements, marking out, drilling, refining the holes and ensuring the parts fit in correctly. ix) Grinding: Upright In the manufacture of grinding wheels, abrasives are preferred to other machining methods due to two major reasons. One is that the quality of work associated with the use of abrasives is higher than that of other machining methods. The second reason is that abrasives can handle harder materials. Basically, abrasive grits have to be bonded in order to come up with grinding wheels. Manufacturers of grinding wheels put into consideration the available grinding machines hence have to ensure that they manufacture different shapes and sizes. Grinding wheels that are properly selected should have the self-sharpening property[Sch3]. The abrasive grits used in the making of the grinding wheels are held in place by the bonds then got into contact with the work. The irregularly shaped grits are able to cut tiny amounts of material to the point of getting blunt. This will consequently lead to the abrasive grit being forced from the bond due to the force applied by the work on them. Factors to consider in the selection of grinding wheels There are several factors that manufacturers of grinding wheels have to consider in their effort to come up with grinding wheels. The four major treasons are as stated below: I) Grit size II) The abrasive material available III) The wheel structure required IV) The strength of the bond Generally, the abrasive material for use should be selected based on the material the users of the grinding wheel will be grinding. Bauxite, which scientifically known as Aluminum oxide is among the hardest grit materials available for use. It is used when carbon steels (hardened) are to be ground[Sch3]. Manufacturers also make use of silicon carbide since its hardness is greater as compared to bauxite. It’s also found to be more brittle hence can only be used to work on brittle materials like cast iron and glass[Sch3]. In considering the grit size, the manufacturer has the nature of the finish intended on the surface. Smaller grits produce a finer finish but it takes longer for this nature of work. Bond strength can be literally interpreted as how soft or hard the grinding wheel is. When the work material in question is hard the grits get blunt more quickly. When the work material is soft on the other hand, the grinding wheel’s surface gets clogged at a faster rate. The work logic applied is that soft grinding wheels are to be used on hard materials in order to have the grits come off readily upon being blunted[Sch3]. Bond materials can either be resinoid, vitrified, rubber or shellac. Each material offers its own special advantages. Resinoid bonds withstand more shock as compared to vitrified bonds thus are better in the removal of metals. Vitrified materials display stability and good strength. Rubber bonds find their application when the wheels are to be flexible. The shellac bond materials are used in the trimming of carbide tips[Sch3]. x) Pneumatics and Control : Air control switch Pneumatic systems are among several systems that are used in industries. Their operation depends on compressed air. Machines called compressors are used to supply compressed air to the pneumatic systems[Sch5]. Manufacturers have been able to develop different sizes and shapes of compressors but they basically operate in the same way. Pneumatic systems are made by assembling several of its components. These include: I) Cylinders ii) Actuators These are basically push buttons that can be used to control 3/2 valves iii) Automated circuits iv) 3/2 Valves Valves are used to regulate the flow of the compressed air to the cylinder. They basically turn the compressed air on or off and regulate the direction towards which the air is flowing. The 3/2 valve is commonly used for this purpose[Sch5]. This valve is called so since it has 3 ports and 2 states. The port enables the connection of a pipe. A state is any position in which a valve can be in. v) 5/2 valves They are mainly used to operate double acting cylinders since the 3/2 valves are not as efficient as they are. They have 5 ports and 2 states[Sch5]. vi) PLC controls Viii) Circuit Simulation software ix) AND control circuits These help in the prevention of accidents by making sure that the guards are the right position right before the machines are switched on. Consequently, they ensure that the machines are not switched on accidently by operators[Sch5]. x) OR controls Pneumatic systems are usually preferred to other reasons due to the following reasons: i) They are clean Pneumatic systems utilize compressed air hence are cleaner.in the case that leaks develop, It is the air that escapes, explaining the reason they are cleaner. Oil based systems because a mess since oil is prone to dripping. i) They are safe Pneumatic systems have a higher degree of safety in their use as compared to other systems. ii) They are reliable They are usually more reliable and can work for a long time. Pneumatic systems barely require maintenance of any sort. iii) They are economical Compressed air used in the pneumatic systems is readily available in most companies for other purposes hence the expenses associated with the use of these systems are minimal. V) They exhibit flexibility Pneumatic systems can be used to carry out a number of tasks and can easily be installed. xi) Welding and Joining: Welding the base with upright and pipes on upright by Oxygen and acetylene. Oxygen and acetylene are used in welding by having an oxyacetylene flame burning at 3500 degrees Celsius. The very hot flame is directed towards a steel surface and right upon coming into contact, the surface is caused to melt and a molten pool is formed. This forms the basis of the welding process to occur. The welding process. i) One should carefully and steadily open the main valve on the tank containing the acetylene. At the same time, one should adjust the pressure to five pounds to square inch. ii) Check for a needle valve located on the torch and open it, while adjusting the pressure to 5PSI. One should do the readings on the acetylene regulators. Close the valve. The ignition phase i) Begin by turning on the acetylene then igniting it to produce a flame. Some amount of soot is expected on this flame’s tip. ii) Increase the amount of acetylene and slowly turn on the oxygen. iii) Increase the amount of oxygen rapidly and that of acetylene slowly. This should produce a localized flame which is what should be utilized for the welding. iv) Welding should be followed by the joining of the base with upright and the pipes. Section 2 Other processes that can be used to manufacture the parts of the air motors. i) Laser cutting for the manufacture of the mount of the air motor In this process, the manufacturer makes use of laser beams to make a defined cut through sheets of metal[Sch]. The beam is generated from a power source, then upon the beam striking the surface, melting or vaporization of the metal occurs and the remains blown away by running gas. The process is usually computer controlled and manufacturers try as much as they can to minimize the materials lost during the cutting[Sch]. Materials on which laser cutting should be done should display low conductivity and reflectivity. There are other materials such as copper alloys that higher conductors of heat and reflect of light can be dealt with using laser beams that are more powerful[Las13]. This process is thus suitable for the manufacture of the mount of the air motor. ii) Plasma cutting in the manufacture of the upright and base Plasma cutting utilizes plasma in the cutting through of the sheet metal. The ionized gases which are at a high temperature are made to flow at a high velocity. They are usually directed to the location where cutting should occur by a nozzle[Sch]. The flow of gases from the nozzle blows away the molten metal leaving a clear cut. This process is also computer controlled in order to have the best defined cut. The use of CNC Machines makes the cuts to be highly precise and can enable manufacturers to come up with complex cuts[Har15]. Section 3 The process of manufacturing an air motor is an aggregate of many other manufacturing processes. These processes are applied to each basic components of the air motor hence giving one an experience of how the air motor is made from scratch. The whole process is rather dynamic since one has to ensure that they go an extra mile in the selection of the right materials and equipment for use in the manufacture of the basic components. This also entitles one to knowing the existing alternatives available in the industry for the manufacture of these components. An opportunity to try each process out makes it possible for a learner to interact more with the course material. Learning these process is the beginning of the experience that every engineering student should have in order to be competent enough in the industry. In having the final assembly of the air motor work, there is satisfaction that a learner is bound to experience knowing that they have properly understood the course material both theoretically and theoretically. References Sch2: , (Engineering, n.d.), Sch4: , (Engineering, n.d.), Har15: , (Khemani, 2015), Sch1: , (Engineering, n.d.), Las13: , (LaserMaster, 2013), Ino10: , (Service, 2010), Sch: , (Engineering, n.d.), Sch3: , (Engineering, n.d.), Sch5: , (Engineering, n.d.), Read More