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| Line 27: |
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| | | | |
| − | =Gate 3: Coordination Review=
| |
| | | | |
| − |
| |
| − | ==Intro==
| |
| − |
| |
| − | Group 9 did not encounter any major issues with the work and management plans. Group 9 met at least once per week to discuss the progress of the Coordination Review. Each member has contributed valuable input to the review. The group as a whole has met and discussed which member would be focusing on which objectives. Also, the group has made a conscious effort to complete the review in a punctual manner. The group’s individuals were assigned specific parts of gate 3. This made working towards finishing the gate much more efficient. The group put all of the individual assignments together and proof-read them to make sure they were sufficient and correct. This made the group use both the strengths of working as a group and as individuals to complete the gate.
| |
| − |
| |
| − | ==Causes for Corrective Action==
| |
| − |
| |
| − | The group had some road blocks, and had to work around the holiday of thanksgiving. The group would have liked to have the gate done quicker than it happened, yet the group got delayed because of the 5 day weekend. This delay should have been planned into the work schedule that the group had composed. One of the group members email went down, which made communication throughout the group harder. This was over come by communicating via text messaging. These issues were resolved in time for the gate to be completed on time.
| |
| − |
| |
| − | ==Engine Components List==
| |
| − |
| |
| − | {| border="1" align="center"
| |
| − | |+ '''Table 1: GM 4 Cylinder Engine Parts List'''
| |
| − | !width="100"|Part Number!! width="100"|Part Name !! width="50"|Quantity !! width="50"|Complexity!! width="100"|Material !! width="300"|Function !! width="100"|Manufacturing Process !!width="100"|Image
| |
| − | |-
| |
| − |
| |
| − | | align="center"|1a
| |
| − | | align="center"|Water Pump Pulley
| |
| − | | align="center"|1
| |
| − | | align="center"|2
| |
| − | | align="center"|Steel
| |
| − | | align="center"|Converts mechanical energy from the crankshaft through belt drive system and uses the energy to rotate the water pump
| |
| − | | align="center"|Stamped - Machined
| |
| − | | [[Image:Waterpumppulley.JPG|center|300px]]
| |
| − | |-
| |
| − |
| |
| − | | align="center"|1b
| |
| − | | align="center"|13 mm Bolts
| |
| − | | align="center"|3
| |
| − | | align="center"|1
| |
| − | | align="center"|Steel
| |
| − | | align="center"|Holds water pump pulley in place
| |
| − | | align="center"|Machined
| |
| − | | align="center"|Pictured Above
| |
| − | |-
| |
| − |
| |
| − |
| |
| − | | align="center"|2a
| |
| − | | align="center"|Serpentine Belt Tensioner
| |
| − | | align="center"|1
| |
| − | | align="center"|3
| |
| − | | align="center"|Hard Plastic, Aluminum, Steel
| |
| − | | align="center"|The belt is connected to the drive pulley of the engine creating more tension which supplies power to the belt drive system
| |
| − | | align="center"|Die Cast - Molded - Machined
| |
| − | | [[Image:serpentinebelttensioner.JPG|center|300px]]
| |
| − | |-
| |
| − |
| |
| − |
| |
| − | | align="center"|2b
| |
| − | | align="center"|16 mm Bolt
| |
| − | | align="center"|1
| |
| − | | align="center"|1
| |
| − | | align="center"|Steel
| |
| − | | align="center"|Keeps serpentine belt tensioner in place
| |
| − | | align="center"|Machined
| |
| − | | align="center"|Pictured Above
| |
| − | |-
| |
| − |
| |
| − | | align="center"|3a
| |
| − | | align="center"|Idler Pulley
| |
| − | | align="center"|1
| |
| − | | align="center"|2
| |
| − | | align="center"|Steel
| |
| − | | align="center"|It acts a tensioner (keeps tension in system) and a guide for the belt which prevents it from coming off the main pulleys and reduces vibration
| |
| − | | align="center"|Molded - Machined - Milling
| |
| − | | [[Image:idlerpulley.JPG|center|300px]]
| |
| − | |-
| |
| − |
| |
| − |
| |
| − | | align="center"|3b
| |
| − | | align="center"|16 mm Bolts
| |
| − | | align="center"|2
| |
| − | | align="center"|1
| |
| − | | align="center"|Steel
| |
| − | | align="center"|Keeps idler pulley in place.
| |
| − | | align="center"|Machined
| |
| − | | align="center"|Pictured Above
| |
| − | |-
| |
| − |
| |
| − |
| |
| − | | align="center"|4
| |
| − | | align="center"|Water Pump
| |
| − | | align="center"|1
| |
| − | | align="center"|4
| |
| − | | align="center"|Steel, Aluminum
| |
| − | | align="center"|Circulates water throughout the engine to prevent it from overheating and reduces friction
| |
| − | | align="center"|Die Cast - Machined - Stamped - Pressed - Molded
| |
| − | | [[Image:waterpump.JPG|center|300px]]
| |
| − | |-
| |
| − |
| |
| − | | align="center"|5
| |
| − | | align="center"|Crank Shaft
| |
| − | | align="center"|1
| |
| − | | align="center"|5
| |
| − | | align="center"|Steel, Aluminum
| |
| − | | align="center"|Transmits power from the pistons and connecting rods into shaft work
| |
| − | | align="center"|Cast - Machined
| |
| − | | [[Image:crankshaft3.JPG|center|300px]]
| |
| − | |-
| |
| − |
| |
| − | | align="center"|6
| |
| − | | align="center"|Timing Chain Cover
| |
| − | | align="center"|1
| |
| − | | align="center"|4
| |
| − | | align="center"|Aluminum
| |
| − | | align="center"|Holds the timing chain against the timing sprocket and protects timing chain from debris
| |
| − | | align="center"|Stamped
| |
| − | | [[Image:timingchaincover.JPG|center|300px]]
| |
| − | |-
| |
| − |
| |
| − | | align="center"|7a
| |
| − | | align="center"|Camshaft Plate
| |
| − | | align="center"|1
| |
| − | | align="center"|2
| |
| − | | align="center"|Steel
| |
| − | | align="center"|Holds camshaft in place and prevents debris from entering camshaft
| |
| − | | align="center"|Stamped
| |
| − | | [[Image:camshaftgasket.JPG|center|300px]]
| |
| − | |-
| |
| − |
| |
| − | | align="center"|7b
| |
| − | | align="center"|10 mm Bolts
| |
| − | | align="center"|3
| |
| − | | align="center"|1
| |
| − | | align="center"|Steel
| |
| − | | align="center"|Holds camshaft plate in place
| |
| − | | align="center"|Machined
| |
| − | | align="center"|Pictured Above
| |
| − | |-
| |
| − |
| |
| − | | align="center"|8
| |
| − | | align="center"|Oil Pump Drive
| |
| − | | align="center"|1
| |
| − | | align="center"|4
| |
| − | | align="center"|Steel, Aluminum, Rubber
| |
| − | | align="center"|Secures camshaft in place and drives the oil pump based on input from the camshaft
| |
| − | | align="center"|Cast - Extruded - Machined - Molded
| |
| − | | [[Image:oilpumpdrive.JPG|center|300px]]
| |
| − | |-
| |
| − |
| |
| − | | align="center"|9
| |
| − | | align="center"|Camshaft
| |
| − | | align="center"|1
| |
| − | | align="center"|3
| |
| − | | align="center"|Steel, Aluminum
| |
| − | | align="center"|Timing mechanism used to open and close the valves for the combustion process
| |
| − | | align="center"|Cast - Machined
| |
| − | |[[Image:camshaft2.JPG|center|300px]]
| |
| − | |}
| |
| − |
| |
| − |
| |
| − | ----
| |
| − |
| |
| − | ==Component Discussion==
| |
| − |
| |
| − | '''Why were different materials used for different components?'''
| |
| − |
| |
| − | The components all must be sturdy enough to withstand the pressures and forces that act on a functioning internal combustion engine. The engine itself is subjected to intense temperatures and pressures. For an internal combustion engine, the list of materials is quite short because the materials must be strong and also cost effective. For the GM 2.2 L 4 cylinder inline engine components, the materials used are:
| |
| − |
| |
| − | *Steel
| |
| − | *Aluminum
| |
| − | *Hardened Plastics
| |
| − | *Rubber (used for forming a seal)
| |
| − |
| |
| − | The majority of the components are made almost entirely of steel. Tempered steel is relatively low in cost and provides a sturdy structure that will withstand the high temperatures and pressures faced inside the cylinders. Also stands well against high tensions ans shear forces.
| |
| − | The second most abundant material used in the components is aluminium. Aluminium is light but more costly than the steel. The aluminum is used in areas that require less weight and do not need to withstand as much forces as the steel. Engineers who designed the components had to find a balance between weight and strength. A component that is in direct contact with the high temperatures and pressures will be made almost entirely of the steel. Components containing aluminium are used to reduce the total weight of the engine without sacrificing stability.
| |
| − | Hardened plastics are relatively cheap and easy to make. In the engine, plastics appear in the form of pulleys. The pulleys need to be strong enough to transmit power to and from the various systems without letting the belts slip. Since the pulleys are not indirect contact with the cylinders, they can be made of plastic. The hardened plastics will not melt or deform and are very light, so they are perfect for the pulleys.
| |
| − | Rubber is not used much in the selected components. Rubber in the engine is used primarily to form seals. For this reason, rubber functions as a seal in both the oil pump drive and the water pump. The rubber prevents oil from escaping the oil pump drive and water from leaving the water pump.
| |
| − | The materials that make-up each component are included on the engine parts list.
| |
| − |
| |
| − | '''Cosmetic vs Functional'''
| |
| − |
| |
| − | All the components listed in our engine are functional. Each component contributes something to the overall functioning of the engine. Engines are typically located under the hood of a car and are thus not meant to be seen. Since engines are hidden, there isn't usually a need to add cosmetic parts.
| |
| − |
| |
| − |
| |
| − | '''Complexity'''
| |
| − |
| |
| − | Complexity is used to characterize something with many parts in intricate arrangement also on the difficulty in manufacturing the parts. In the above table (1) is given to the least complex whereas (5) to the most.
| |
| − |
| |
| − | ==Component Analysis==
| |
| − |
| |
| − | ===Water Pump Pulley===
| |
| − |
| |
| − |
| |
| − | '''What material is used?'''
| |
| − |
| |
| − | Steel
| |
| − |
| |
| − | '''Why?'''
| |
| − |
| |
| − | There is a lot of friction within this component creating high temperature and steel is an ideal material when dealing with extreme heat because of its high resistance.
| |
| − |
| |
| − | '''What forces are applied to the component?'''
| |
| − |
| |
| − | There are frictional and tension forces exerted on the pulley.
| |
| − |
| |
| − | '''Force estimate'''
| |
| − |
| |
| − | The tension force is estimated at 50 to 100 N.
| |
| − |
| |
| − | '''Does the material choice affect the manufacturing process?'''
| |
| − |
| |
| − | Yes, certain materials would not be able to withstand such high temperatures and therefore not function properly.
| |
| − |
| |
| − | '''What is the components shape?'''
| |
| − |
| |
| − | The Water Pump Pulley is a circle with raised edges designed to fit on the water pump. It also has holes on the face of it for bolt attachment.
| |
| − |
| |
| − | '''Why?'''
| |
| − |
| |
| − | The circular shape is chosen because this component operates as a pulley using rotational dynamics in which this shape is ideal.
| |
| − |
| |
| − | '''Does the shape affect the manufacturing process?'''
| |
| − |
| |
| − | The circular shape of the water pump pulley is most easily stamped and cleaned-up with light machining. It would be unnecessary to manufacture using other processes.
| |
| − |
| |
| − | '''Why was the manufacturing process chosen?'''
| |
| − |
| |
| − | Stamping was chosen for this product so that it can be mass produced with precision.
| |
| − |
| |
| − | '''How complex is the component?'''
| |
| − |
| |
| − | The part can be easily manufactured by stamping thus not being that complex. Also, a pulley is a very simple machine that transmits power around a circular shape.
| |
| − |
| |
| − |
| |
| − | ===Serpentine Belt Tensioner===
| |
| − | '''What material is used?'''
| |
| − |
| |
| − | Hard Plastic, Aluminum, Steel
| |
| − |
| |
| − | '''Why?'''
| |
| − |
| |
| − | Plastic is used for its physical property of not needing any lubrication, it has reduced wear on it and the parts in contact with it, it is inexpensive and corrosion resistant. Aluminum is used because it is soft, light and also corrosion resistant. Steel was used in this component because of its high tensile strength and high resistant against corrosion.
| |
| − |
| |
| − | '''What forces are applied to the component?'''
| |
| − |
| |
| − | There are frictional forces exerted on the tensioner.
| |
| − |
| |
| − | '''Force estimate'''
| |
| − |
| |
| − | The tension force is estimated at 50 to 100 N.
| |
| − |
| |
| − | '''Does the material choice affect the manufacturing process?'''
| |
| − |
| |
| − | Yes. Plastic cannot be machined and must be injected into a mold. The die-cast parts were produced as so because they are easily mass produced whereas the machined parts were done because of a required precision.
| |
| − |
| |
| − | '''What's the components shape?'''
| |
| − |
| |
| − | The component consists of a cylinder with a protruding arm attached to a second cylinder.
| |
| − |
| |
| − | '''Why?'''
| |
| − |
| |
| − | The circular shape is chosen because this component operates as a pulley using rotational dynamics in which this shape is ideal. This reduces friction.
| |
| − |
| |
| − | '''Does the shape affect the manufacturing process?'''
| |
| − |
| |
| − | No the process is unaffected by the shape, because plastic can be molded into a cylinder quite easily. This shape is not a hard shape to mold, so there would be no problems during the molding process.
| |
| − |
| |
| − | '''Why was the manufacturing process chosen?'''
| |
| − |
| |
| − | Plastic can be easily molded, whereas metals can be easily machined and die cut using appropriate tools.
| |
| − |
| |
| − | '''How complex is the component?'''
| |
| − |
| |
| − | This is one of the most complex components of our product as it's manufactured from three different materials; it consists of a cylinder with a protruding arm attached to a second cylinder, which operates as a pulley for which the shape is ideal.
| |
| − |
| |
| − |
| |
| − | ===Idler Pulley===
| |
| − | '''What material is used?'''
| |
| − |
| |
| − | Steel
| |
| − |
| |
| − | '''Why?'''
| |
| − |
| |
| − | Steel was used in this component because of its high tensile strength and high resistance against corrosion.
| |
| − |
| |
| − | '''What forces are applied to the component?'''
| |
| − |
| |
| − | There are tension forces present.
| |
| − |
| |
| − | '''Force estimate'''
| |
| − |
| |
| − | The tension forces are estimated at 50 to 100 N.
| |
| − |
| |
| − | '''Does the material choice affect the manufacturing process?'''
| |
| − |
| |
| − | The same results can be achieved using a different metal as well.
| |
| − |
| |
| − | '''What's the components shape?'''
| |
| − |
| |
| − | The Idler Pulley is a circle with raised edges. It also has holes on the face of it for attachment via bolts.
| |
| − |
| |
| − | '''Why?'''
| |
| − |
| |
| − | The circular shape is chosen because this component operates as a pulley using rotational dynamics in which this shape is ideal.
| |
| − |
| |
| − | '''Does the shape affect the manufacturing process?'''
| |
| − |
| |
| − | No, the shape of the idler pulley does not make it so it can not be milled, or molded. Machining is also not a problem with this shape.
| |
| − |
| |
| − | '''Why was the manufacturing process chosen?'''
| |
| − |
| |
| − | Milling was required for the holes, which reduces the weight. Molding parts are easily and accurately reproduced. Machining was used to produce a smooth finish to reduce friction
| |
| − |
| |
| − | '''How complex is the component?'''
| |
| − |
| |
| − | This component is fairly simple as it consists of just one circular part with holes in it. It can be easily molded and the holes can be milled accurately.
| |
| − |
| |
| − |
| |
| − | ===Water Pump===
| |
| − | '''What material is used?'''
| |
| − |
| |
| − | Steel and Aluminum
| |
| − |
| |
| − | '''Why?'''
| |
| − |
| |
| − | Aluminum is used for it's soft, light and also corrosion resistant properties. Steel was used in this component because of its high tensile strength and high resistance against corrosion.
| |
| − |
| |
| − | '''What forces are applied to the component?'''
| |
| − |
| |
| − | There are tension forces present
| |
| − |
| |
| − | '''Force estimate'''
| |
| − |
| |
| − | These forces are estimated at 50 to 100N
| |
| − |
| |
| − | '''Does the material choice affect the manufacturing process?'''
| |
| − |
| |
| − | Yes, steel is harder to machine than aluminum because aluminum is softer and needs to be more precise.
| |
| − |
| |
| − | '''What is the components shape?'''
| |
| − |
| |
| − | A triangular mount with a small shaft attached to a small rotor.
| |
| − |
| |
| − | '''Why?'''
| |
| − |
| |
| − | This is required because it needs to take the rotational energy through the shaft to move water throughout the cooling system.
| |
| − |
| |
| − | '''Does the shape affect the manufacturing process?'''
| |
| − |
| |
| − | Yes, the intricate shape required, casting, pressing, machining, and molding to manufacture.
| |
| − |
| |
| − | '''Why was the manufacturing process chosen?'''
| |
| − |
| |
| − | The steel components were cast and pressed, the shaft was machined, and the rotor was molded. These components are most accurately and cost effectively produced in this manner.
| |
| − |
| |
| − | '''How complex is the component?'''
| |
| − |
| |
| − | This component is very complex because it's made of two different materials as well as it would be an intricate process to construct the required shape for the component.
| |
| − |
| |
| − | ===Crankshaft===
| |
| − | '''What material is used?'''
| |
| − |
| |
| − | Steel and Aluminum
| |
| − |
| |
| − | '''Why?'''
| |
| − |
| |
| − | Steel was used in this component because of its high tensile strength and high resistance against corrosion. Aluminum is used for its soft, light and also corrosion resistance properties.
| |
| − |
| |
| − | '''What forces are applied to the component?'''
| |
| − |
| |
| − | The weight and movement of pistons due to combustion.
| |
| − |
| |
| − | '''Force estimate'''
| |
| − |
| |
| − | From our calculations, the force is approximately 4000 N.
| |
| − |
| |
| − | '''Does the material choice affect the manufacturing process?'''
| |
| − |
| |
| − | Steel and Aluminum are most workable through machining processes.
| |
| − |
| |
| − | '''What is the components shape?'''
| |
| − |
| |
| − | Several cylinders and circular plates of various diameters offset from a center axis.
| |
| − |
| |
| − | '''Why?'''
| |
| − |
| |
| − | The cylinders and plates separate and time the pistons.
| |
| − |
| |
| − | '''Does the shape affect the manufacturing process?'''
| |
| − |
| |
| − | Yes, many of the components can be cast but need to be machined for precision.
| |
| − |
| |
| − | '''Why was the manufacturing process chosen?'''
| |
| − |
| |
| − | Yes, a smooth finish is required for the cylinders to reduce friction between them and the connecting rods of the pistons.
| |
| − |
| |
| − | '''How complex is the component?'''
| |
| − |
| |
| − | This is the most complex component as it has several cylinders and circular plates of various diameters, it also needs to have a smooth finishing to reduce friction.
| |
| − |
| |
| − |
| |
| − | ===Timing Chain Cover===
| |
| − | '''What material is used?'''
| |
| − |
| |
| − | Aluminum
| |
| − |
| |
| − | '''Why?'''
| |
| − |
| |
| − | Aluminum is used for its soft, light and also corrosion resistant properties.
| |
| − |
| |
| − | '''What forces are applied to the component?'''
| |
| − |
| |
| − | The force on this component is the weight of the pulleys.
| |
| − |
| |
| − | '''Force estimate'''
| |
| − |
| |
| − | The pulleys weigh approximately 10 to 20 N combined.
| |
| − |
| |
| − | '''Does the material choice affect the manufacturing process?'''
| |
| − |
| |
| − | Yes, because aluminum's softness makes it ideal for stamping.
| |
| − |
| |
| − | '''What's the components shape?'''
| |
| − |
| |
| − | This is an oval with a protruding circle at one end.
| |
| − |
| |
| − | '''Why?'''
| |
| − |
| |
| − | This is meant to cover the timing chain and provide support for the pulleys.
| |
| − |
| |
| − | '''Does the shape affect the manufacturing process?'''
| |
| − |
| |
| − | Yes, because this shape cannot easily be machined or cast, it is much easier to stamp this component.
| |
| − |
| |
| − | '''Why was the manufacturing process chosen?'''
| |
| − |
| |
| − | The timing chain cover does not need to be smooth and aluminum is easily stamped and reproduced.
| |
| − |
| |
| − | '''How complex is the component?'''
| |
| − |
| |
| − | This part is not that complex as it can be easily stamped and also it need not to be smooth.
| |
| − |
| |
| − |
| |
| − | ===Camshaft Plate===
| |
| − | '''What material is used?'''
| |
| − |
| |
| − | Steel
| |
| − |
| |
| − | '''Why?'''
| |
| − |
| |
| − | Steel was used in this component because of its high tensile strength and high resistance against corrosion.
| |
| − |
| |
| − | '''What forces are applied to the component?'''
| |
| − |
| |
| − | The bolts holding plate in place.
| |
| − |
| |
| − | '''Force estimate'''
| |
| − |
| |
| − | These are approximately 3 N.
| |
| − |
| |
| − | '''Does the material choice affect the manufacturing process?'''
| |
| − |
| |
| − | No, it is still able to be stamped with it being steel.
| |
| − |
| |
| − | '''What's the components shape?'''
| |
| − |
| |
| − | This component is a circle with three equally spaced protruding miniature circles.
| |
| − |
| |
| − | '''Why?'''
| |
| − |
| |
| − | The protruding circles are present for attachment purposes.
| |
| − |
| |
| − | '''Does the shape affect the manufacturing process?'''
| |
| − |
| |
| − | This shape is most easily and efficiently stamped.
| |
| − |
| |
| − | '''Why was the manufacturing process chosen?'''
| |
| − |
| |
| − | This component is most effectively and mass produced in the stamping process.
| |
| − |
| |
| − | '''How complex is the component?'''
| |
| − |
| |
| − | This is a fairly simple component as it can be stamped easily and efficiently.
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| − |
| |
| − | ===Oil Pump Drive===
| |
| − | '''What material is used?'''
| |
| − |
| |
| − | Steel, Aluminum and Rubber
| |
| − |
| |
| − | '''Why?'''
| |
| − |
| |
| − | Aluminum is used for its soft, light and also corrosion resistant. Steel was used in this component because of its high tensile strength and high resistance against corrosion. Rubber is used for its ability to create a firm seal.
| |
| − |
| |
| − | '''What forces are applied to the component?'''
| |
| − |
| |
| − | There are rotational forces present.
| |
| − |
| |
| − | '''Force estimate'''
| |
| − |
| |
| − | The rotational force is estimated to be 30 to 40 N-m
| |
| − |
| |
| − | '''Does the material choice affect the manufacturing process?'''
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| − |
| |
| − | The gear was cast, the steel shaft was machined, and the rubber was molded into a ring.
| |
| − |
| |
| − | '''What's the components shape?'''
| |
| − |
| |
| − | There are several cylinders attached at their central axis with a protruding edge for attachment via bolt. There is also a main gear.
| |
| − |
| |
| − | '''Why?'''
| |
| − |
| |
| − | The gear's purpose is to attach to the camshaft, hold them in place and drive the oil pump.
| |
| − |
| |
| − | '''Does the shape affect the manufacturing process?'''
| |
| − |
| |
| − | Yes, this gear needed to be very precise, which caused it to be machined.
| |
| − |
| |
| − | '''Why was the manufacturing process chosen?'''
| |
| − |
| |
| − | Machining provides a smooth surface for less friction of the gear.
| |
| − |
| |
| − | '''How complex is the component?'''
| |
| − |
| |
| − | This component is complex as it uses three different materials for manufacturing, the gear, the steel shaft and the rubber ring. Its shape also has to be very precise and smooth to limit friction.
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| − |
| |
| − |
| |
| − | ===Camshaft===
| |
| − | '''What material is used?'''
| |
| − |
| |
| − | Steel and Aluminum
| |
| − |
| |
| − | '''Why?'''
| |
| − |
| |
| − | Aluminium is used for its soft, light and also corrosion resistant. Steel was used in this component because of its high tensile strength and high resistance against corrosion.
| |
| − |
| |
| − | '''What forces are applied to the component?'''
| |
| − |
| |
| − | There are rotational forces and forces due to the push rods
| |
| − |
| |
| − | '''Force estimate'''
| |
| − |
| |
| − | The estimated rotational forces are 100 to 150 N-m and the push rod forces are estimated at 50 to 100 N.
| |
| − |
| |
| − | '''Does the material choice affect the manufacturing process?'''
| |
| − |
| |
| − | Yes, these metals are easily machined and cast. Aluminum is used more in the machining whereas the steel components are cast.
| |
| − |
| |
| − | '''What is the components shape?'''
| |
| − |
| |
| − | The camshaft is composed of a long shaft with several lobes placed along the length of the camshaft.
| |
| − |
| |
| − | '''Why?'''
| |
| − |
| |
| − | The placement of the lobes is determined by where the pushrods are placed.
| |
| − |
| |
| − | '''Does the shape affect the manufacturing process?'''
| |
| − |
| |
| − | The camshaft is generally made on a lathe but, the lobes are cast and machined separately.
| |
| − |
| |
| − | '''Why was the manufacturing process chosen?'''
| |
| − |
| |
| − | Lathes produce smooth cylindrical finishes.
| |
| − |
| |
| − | '''How complex is the component?'''
| |
| − |
| |
| − | This is a fairly complex component as it's composed of a long shaft with several lobes along its length. It has a smooth cylindrical finish which has to be cast and machined separately.
| |
| − |
| |
| − | ==Design Revisions==
| |
| − |
| |
| − | The design changes Group 9 is suggesting are intended to make the engine lighter, cost effective and performance driven.
| |
| − |
| |
| − | *'''Camshaft configuration'''
| |
| − |
| |
| − | *In the GM 2.2L Four Cylinder Inline engine the camshaft configuration is a pushrod system. Group 9 would recommend to the manufacturer a switch to an overhead camshaft system either single (SOHC) or double (DOHC). The current pushrod system is less efficient than an overhead cam system.
| |
| − |
| |
| − | *Pushrod timing systems have an in-block camshaft located below the cylinders. Thin rods of metal called pushrods which are usually 8-10 inches in length ride on top of the lobes of the camshaft. As the camshaft spins the lobes push the pushrods up which move the rocker arms up and open the valves into the cylinder. In the pushrod system more material is needed to make the pushrods and the timing of the valves is not at its peak efficiency. Pushrods add mass to the system and increase the load on the springs which greatly limits the performance of the engine. A camshaft that is mounted above the cylinders and directly next to the rocker arms is more desirable.
| |
| − |
| |
| − | *Single Overhead Cam (SOHC) systems have the camshaft located directly above the cylinders and next to the rocker arms. Not only does this improve performance but it reduces costs and the total weight of the engine. Without the pushrods the chance for failure is greatly reduced and the energy of the camshaft is directly exchanged into the rocker arms and valves. The overhead camshaft system is just plainly simpler but at the same time more efficient. In overhead camshaft systems the timing must be perfect otherwise the pistons may hit the valves. This problem is avoided by the timing chain which connects the camshaft(s) to the crankshaft.
| |
| − |
| |
| − | *Double Overhead Cam (DOHC) systems are almost exactly the same as the SOHC system except instead of one camshaft per head there are two. For example in a V-4 engine there would be two overhead cams for a SOHC system or four overhead cams for a DOHC system. In a V shaped engine there are two heads so there must be at least one cam per head. The GM 4 cylinder inline could have either one or two overhead cams because there is only one head. The major disadvantage to two cams per head would be an increase of weight but at the same time it is increasing performance. A balance between weight and performance must be made for the best efficiency. Two cams are preferable for performance and one is preferable for keeping costs down. Overall, a change from the pushrod system to an overhead mounted cam would improve the engines functionality, reliability and reduces maintenance.
| |
| − |
| |
| − | *'''Cylinder/Piston Size'''
| |
| − |
| |
| − | *One of the biggest performance improvements that can be made to a stock engine like the GM 2.2L Four Cylinder Inline engine is to increase the cylinder and piston size.
| |
| − |
| |
| − | *The concept of increasing the enclosed volume of the cylinder to improve performance is widely known in engine manufacturing. The way a company would increase the size of the cylinder is to take the bare engine block and bore out the cylinders with a mill. From intuition, the more air that can be compressed and ignited with fuel, the better the engine will perform. Cylinders can be bored with great precision by a milling machine. One small mistake in this process would result in a major problem with the combustion process. The pistons must fit perfectly within the cylinders creating limited friction and an impenetrable seal of the combustion chamber. If this is not achieved then either the piston and cylinder wall may crack or the combustion process will be incomplete or highly inefficient.
| |
| − |
| |
| − | *An advantage of the increased cylinder size is more performance out of the same engine block. When the cylinder is bored it must still have enough cylinder wall between each cylinder to prevent the engine block from cracking. The pressures inside of an internal combustion engine are enormous so the cylinders must have enough strength to overcome all the forces applied to them.
| |
| − |
| |
| − | *The biggest disadvantage to boring the cylinders wider is cost. Since the milling process is highly precise it is quite costly. However, if performance is an issue to the company then this is an improvement that should be considered. Another issue with a larger cylinder is the limitation based on the piston sizes. The pistons must ride perfectly within the cylinders so the size of the cylinder is based on the size of the piston.
| |
| − |
| |
| − | *A precise engine means greater performance but more cost. The reliability and functionality will greatly increase if the cylinders are precisely milled. Increasing the cylinder size will remove material but adding larger pistons adds mass. The balance between cylinder and piston size will keep the weight about the same. If the manufacturer can afford larger, more precise cylinders the design of the engine will be improved.
| |
| − |
| |
| − | *'''Pulleys'''
| |
| − |
| |
| − | *The two main pulleys on the engine are the idler pulley and water pump pulley. They are both made of steel and have vertical grooves along the outside where they come into contact with the belt. Group 9 is suggesting as a design revision the idler pulley and water pump pulley be made completely of aluminum and a different design for the grooves.
| |
| − |
| |
| − | *A pulley’s main function on the engine is to transmit power to and from various components. It is important that the pulleys be lightweight and has enough grip to ensure the belt does not slip.
| |
| − |
| |
| − | *The idler pulley acts as a guide and tensioning device for the belt. If the idler pulley was made of aluminum it would weigh less than steel and there would be no need for the extra holes made in the original. The manufacturer cut holes in a circular pattern to reduce the weight because the steel is very heavy. However, aluminum is already lighter than steel and is strong enough to hold the belt system in place.
| |
| − |
| |
| − | *The water pump pulley takes the energy from the crankshaft and idler pulley to turn the water pump. A water pump is attached to the backside of the water pump pulley and as the belt spins the pulley, the water pump is driven. Efficiency of the water pump depends on the water pump pulley so to make the pulley out of aluminum will make it lighter and faster. The aluminum is costly but in this case worth it.
| |
| − |
| |
| − | *For both pulleys the vertical grooves are not the most efficient way of creating a solid grip of the belt. If the belt has horizontal grooves then the pulleys should have horizontal grooves for the belt to fit into. There is a very small chance of the belt slipping if the design includes matching grooves for the pulleys and belt. The grooves will not increase costs and the reliability and functionality will greatly increase.
| |
| − |
| |
| − |
| |
| − | ==Solid Modeling==
| |
| − |
| |
| − |
| |
| − | All of the solid modeling was done in Pro Engineer 4.0 because of its common use and convenience. The parts chosen were the camshaft, oil pump drive and bolt, and serpentine belt tensioner. The parts were chosen for their complexity and for their importance in functioning of the product. The camshaft and the oil pump drive were chosen for their unique interaction. The camshaft and the oil pump drive function simultaneously to drive the oil pump. The oil pump drive bolt functions to secure the oil pump drive and thus it is an important part of the process. The serpentine belt tensioner also plays a key role in the functioning of the system. The serpentine belt tensioner creates tension to supply power to the belt drive system.
| |
| − |
| |
| − |
| |
| − | ===Parts===
| |
| − |
| |
| − | [[Image:CAMSHAFTinf.JPG|center|400px|thumb|Camshaft Modeled in Pro Engineer Wildfire 4.0.]]
| |
| − |
| |
| − | [[Image:Oil_Pump_Drive.JPG|center|400px|thumb|Oil Pump Drive Modeled in Pro Engineer Wildfire 4.0.]]
| |
| − |
| |
| − | [[Image:Boltinf.JPG|center|400px|thumb|10 mm Oil Pump Drive Bolt Modeled in Pro Engineer Wildfire 4.0.]]
| |
| − |
| |
| − | [[Image:Serpentine_Belt_Tensioner.JPG|center|400px|thumb|Serpentine Belt Tensioner Modeled in Pro Engineer Wildfire 4.0.]]
| |
| − |
| |
| − |
| |
| − | ===Assembly===
| |
| − |
| |
| − |
| |
| − | [[Image:Asse1.JPG|center|400px|thumb|Assembly Picture 1 in Pro Engineer Wildfire 4.0.]]
| |
| − |
| |
| − | [[Image:Asse2.JPG|center|400px|thumb|Assembly Picture 2 in Pro Engineer Wildfire 4.0.]]
| |
| − |
| |
| − | [[Image:Asse3.JPG|center|400px|thumb|Assembly Picture 3 in Pro Engineer Wildfire 4.0.]]
| |
| − |
| |
| − | [[Image:Asse4.JPG|center|400px|thumb|Assembly Picture 4 in Pro Engineer Wildfire 4.0.]]
| |
| − |
| |
| − | [[Image:Asse5.JPG|center|400px|thumb|Assembly Picture 5 in Pro Engineer Wildfire 4.0.]]
| |
| − |
| |
| − | [[Image:Asse6.JPG|center|400px|thumb|Assembly Picture 6 in Pro Engineer Wildfire 4.0.]]
| |
| − |
| |
| − | ==Engineering Analysis==
| |
| − |
| |
| − | '''Problem Statement:'''
| |
| − | A superheated piston becomes warped inside a cylinder of an internal combustion engine. During the combustion phase of the cycle, the piston begins to move down from the ignition of the air and gas mixture by the spark plug, when it becomes jammed only 1 cm down from its original position. The deformed piston caused a stoppage in the system, which creates a large buildup of pressure inside the cylinder. The built-up pressure over one cycle of the engine is to be determined.
| |
| − |
| |
| − |
| |
| − |
| |
| − | '''Diagram:'''
| |
| − |
| |
| − |
| |
| − |
| |
| − |
| |
| − | [[Image:Diagraminf.jpg |center|400px]]
| |
| − |
| |
| − |
| |
| − |
| |
| − |
| |
| − |
| |
| − | '''Assumptions:'''
| |
| − | *The original piston/cylinder device is frictionless
| |
| − |
| |
| − | *The frictional force of the jammed piston/cylinder device is always greater than or equal to the force of the explosion
| |
| − |
| |
| − | *Original pressure inside cylinder = P1 = 1 atm = 101.325 kPa
| |
| − |
| |
| − | *Original temperature inside cylinder = T1 = 20°C = 293 K
| |
| − |
| |
| − | *Adiabatic combustion temperature of gasoline = T2 = 2300K
| |
| − |
| |
| − | *Cylinder r = 4.4 cm
| |
| − |
| |
| − | *Cylinder h1 = 10.0 cm
| |
| − |
| |
| − | *Ideal gas
| |
| − |
| |
| − | *Rigid tank
| |
| − |
| |
| − |
| |
| − | '''Governing Equations:'''
| |
| − | P_1*V_1/T_1 = P_2*V_2/T_2
| |
| − |
| |
| − | Vcyl. = hπr^2
| |
| − |
| |
| − |
| |
| − | '''Calculations:'''
| |
| − | V_1 = (0.10 m) π (0.044 m)^2 = .000608 m^3
| |
| − | V_2 = (0.11 m) π (0.044 m)^2 = .000669 m^3
| |
| − |
| |
| − | (P_1 V_1)/T_1 = (P_2 V_2)/T_2 → P_2= (P_1 V_1 T_2)/(T_1 V_2 )=((101.325kPa)(.000608 m^3 )(2300 K))/((293 K)(.000669 m^3))=722.86 kPa
| |
| − |
| |
| − |
| |
| − | '''Discussion:'''
| |
| − | In this problem it is expected the pressure after combustion will be much higher than at the original state. Through the calculations we proved this to be true. Since the piston becomes jammed, the pressure that is created during combustion is not fully transferred into mechanical energy because the piston is not moving. This is a problem that can occur in any internal combustion engine if not maintained well. We assumed that the mixture of gasoline and air is an ideal gas acting in the rigid tank known as the piston cylinder. The initial state is characterized by standard temperature and pressure after the air intake. The temperature at which gasoline combusts was found to be around 2300K according to Ecen.com. After the combustion of the gas and air mixture, the piston moves only 1 cm therefore only changing the volume by slight amount. Normally the piston gets shot down due to the rapid increase in pressure which allows the pressure to decrease again. Since the piston is stuck and unable to move, the pressure builds up. This pressure is determined to be 722.9 kPa.
| |
| − |
| |
| − |
| |
| − | '''Engineering Analysis Uses:'''
| |
| − | Engineering analysis is used all throughout the design and testing stages. When designing any product time must be taken to analyze every part. In order for a part to function properly one must consider its purpose and function in the overall product. One must use engineering analysis to determine forces and energies acting on it. One must also design the product to meet consumer wants such as aesthetics (although aesthetics don't typically come in to play with things like car engines). In the case of the example above engineers need to account for the possibility of the piston getting stuck. They need to make a failure modes and effects analysis, like below, to determine the likelihood of the problem and prevention. Then they must achieve a certain factor of safety. Even in testing engineering analysis is used. One must interpret the results of the test with engineering analysis to determine whether they have to return to the design stage (does not suffice requirements) or can move on with production.
| |
| − |
| |
| − |
| |
| − | '''Failure Modes and Effect Analysis:'''
| |
| − | Few pistons simply fail. Most are damaged by a faulty operating environment. These conditions include lack of lubrication, abnormal combustion, the presence of debris within the engine, and clearance issues that lead to physical contact between the piston and another part. Also if the engine injection system is delivering the wrong amount of fuel, at the wrong time or for the wrong duration excessive heating can occur or even erosion. In order to prevent heat build-up that can lead to piston damage, it is important the correct level of lubrication reaches the piston at the skirt and piston pin. Another possibility of piston failure can be caused by contamination from the air intake. Such things can cause scuffing and eventually result in piston failure. Piston failure doesn’t really occur frequently but can occur over time. It can be avoided if caught in time. Drivers can notice this as it can cause fluctuations in oil pressure, higher than normal operating temperatures, unusual noises and change in fuel and oil consumption. Once damaged pistons reach failure the car may be rendered unable to be driven creating a huge safety concern.
| |
| | | | |
| | =Gate 4: Critical Project Review= | | =Gate 4: Critical Project Review= |
Group 9 received a 2.2 liter 4 cylinder gm engine for their reverse engineering project. The engine was nonoperational when received but otherwise in good condition. This project was completed in cooperation with group 24. The engine was divided amongst the two groups with group 9 being responsible for the belt drive system, camshaft and crankshaft. Group 24 on the other hand was responsible for the headers and pistons. The project was to be completed over the course of a semester and was broken down into 5 stages or gates.
Gate 4 is the critical project review. This is where the product was reassembled while keeping the same level of detail as when the product was dissected. At this point the product was reevaluated compared to before the disassembly.
Gate 5 is the delivery. This includes finishing the wiki accompanied by a compliance matrix ensuring the completion of all parts. This stage also encompasses an oral presentation of the results of the project.
The project was successful in achieving the outlined objectives (as outlined in the introduction). The product was disassembled and reassembled successfully while being analyzed along the way. Below are the results of this project.
The main objective of this project was to dissect and analyze an assigned product. Group 9 was given a 2.2 liter 4 cylinder gm engine. The engine was nonfunctioning upon the start of the project. Understanding how products work and how to apply engineering logic to real world products is a very important skill to develop for engineers. This project reinforced these key skills as well as allowed for the improvement of group working skills. This project also gave a chance to showcase technical writing skills and decision making skills.
Group 9 begins their reassembly process with an empty engine block; their tools which includes a socket set, rubber mallet, and Torx screwdriver; and all of the disassembled components mentioned below. For each step a difficulty from 1 to 5 was assigned; one being the easiest, task accomplished with little effort, and five being the most difficult with many attempts required to perform the task correctly.
.JPG)
