Advanced Research Journals of Science and Technology
ADVANCED RESEARCH JOURNALS OF SCIENCE AND TECHNOLOGY
(ARJST)
MANUFACTURING PROCESS FOR CYLINDER FIN BODY FOR 150CC ENGINE
2349-3636
S.C.Jung 1, R. Ohmi2, 1 Research Scholar, Department of Mechanical Engineering,SR. Engineer, china. 2 Professor , Department of Mechanical Engineering, SR. Engineer, china.
Abstract The Engine cylinder is one of the major automobile components, which is subjected to high temperature variations and thermal stresses. In order to cool the cylinder, fins are provided on the cylinder to increase the rate of heat transfer. By doing thermal analysis on the engine cylinder fins, it is helpful to know the heat dissipation inside the cylinder. The principle implemented in this project is to increase the heat dissipation rate by using the invisible working fluid, nothing but air. We know that, by increasing the surface area we can increase the heat dissipation rate, so designing such a large complex engine is very difficult. The main purpose of using these cooling fins is to cool the engine cylinder by any air. In this project a parametric model of the cylinder fin body is created. For manufacturing this pressure die casting is used. we are designing mould base for the cold chamber Furness. Core and cavity are extracted and total mould base is designed for the manufacturing of cylinder fin body. CNC Program is to be generated for both core and cavity using roughing and finishing processes. This is also done in manufacturing module in Pro/Engineer. Modeling, core-cavity extraction and die design is done by using Pro/engineer software.
*Corresponding Author: S.C.Jung , Research Scholar, Department of Mechanical Engineering, SR. Engineer, china Published: August 04, 2014 Review Type: peer reviewed Volume: I, Issue : I
Citation: S.C.Jung ,Research Scholar (2014) MANUFACTURING PROCESS FOR CYLINDER FIN BODY FOR 150CC ENGINE
INTRODUCTION COOLING SYSTEM FOR I.C. ENGINES Internal combustion engines at best can transform about 25 to 35 percentage of the chemical energy in the fuel in to mechanical energy. About 35 percentage of the heat generated is lost in to the surroundings of combustion space, remainder being dissipated through exhaust’ and radiation from the engine. The temperature of the burning gases in the engine cylinder is about 2000 to 2500° C. The engine components like cylinder head, cylinder wall piston and the valve absorb this heat. Such high temperatures are objectionable for various reasons state below. Necessity for Engine Cooling 1) Engine valves warp (twist) due to over heating. 2) Damage to the materials of cylinder body and piston. 3) Lubricating oil decomposes to form gummy and carbon particles. 4) Thermal stresses are set up in the engine parts and
causes distortion (twist or change shape) and cracking of components. 5) Pre – ignition occurs (i.e. ignition occurs before it is required to igniter due to the overheating of spark plug. 6) Reduces the strength of the materials used for piston and piston rings. 7) Overheating also reduces the efficiency of the engine. To avoid the above difficulties, some form of cooling is provided to keep the temperature of engine at the desired level. It should be noted that if the engine becomes every cool the efficiency reduces, because starting the engine from cold requires more fuel. AIR COOLING SYSTEM Air cooling (Direct cooling) In air cooling, air is circulated around the cylinder block and cylinder head, fins are provided outside the cylinder and on the cylinder head. Fins increase the surface area exposed to the atmosphere and the heat radiation from the surface also increases. More air passes over the fins and comes contact with the cylinder, thus the engine heat is removed efficiently. The use of fins increases the heat transfer surface by 5 to 10 times its original value (i.e. without the use of fins). The high velocity of air required for cooling is obtained by the forward motion of the engine (vehicle) itself. In stationary engine, air circulating fan is provided. Disadvantages of air cooling 1. Air cooling is not as effective as water cooling and efficiency of the engine is reduced. 2. Engine parts are not uniformly cooled. The front por-
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Advanced Research Journals of Science and Technology
tion of the engine which faces the air is cooled more than the rear portion. This results in slight distortion. 3. Not suitable for multi-cylinder engines. This requires a separate fan for circulation. 4. Fans used for a stationary engine consumes 5% of engine power. 5. Such engines are suitable only for low horsepower engines. Water cooling (Indirect cooling) In this system, water is circulated around the cylinder and cylinder heat to carry away the heat. The water passes through a passage called “water jacket� There are two methods of water cooling; (i) Natural circulation of water. (ii) Forced circulation of water. MODEL OF CYLINDER FIN BODY
try, and they can be found in thousands of consumer, commercial and industrial products. Die cast parts are important components of products ranging from automobiles to toys. Parts can be as simple as a sink faucet or as complex as a connector housing. Die casting is a method of producing alloy castings by injecting molten metal into metallic mold under pressure. Die casting process can be classified into a) Hot Chamber Process b) Cold Chamber Process HIGH PRESSURE DIE CASTING The four principal metals, with different alloy compositions, that are commonly hot- or cold chamber die cast are aluminium, zinc, magnesium and copper-base alloys. The injection system in the hot chamber machines is immersed into the melt and the pressure is therefore limited. The system also degrades quickly if exposed to aluminium. In the cold chamber process, the metal reservoir is separated from the injection system. The metal is filled into the steel shot sleeve, as shown in Figure 1. The shot sleeve is typically 200-300oC. The hydraulic energy is provided by a computerized system that permits control of metal, position, velocity and plunger acceleration to optimize the flow and the pressure during filling and solidification. The die cavity may be evacuated to reduce air entrapment during die filling, and high integrity die castings can therefore be produced by utilizing vacuum systems. Alternatively semi-solid metalworking (SSM) can be used to reduce turbulence. Contrarily, the quality of conventionally produced die castings has been ensured by the effort and experience given by the machine operators in the foundry. A short die filling time and thin walls result in high cooling rates, (typically 100ÂŹ1000 Ks-1). This promotes a fine grain size which provides decent mechanical properties. However, the properties can be improved by intimate interrelationship between product and process design through amended metal handling, accurate process control, and optimized runner and die design.
DIE CASTING
Cold chamber machines
Die casting is a versatile process for producing engineered metal parts by forcing molten metal under high pressure into reusable steel molds. These molds, called dies, can be designed to produce complex shapes with a high degree of accuracy and repeatability. Parts can be sharply defined, with smooth or textured surfaces, and are suitable for a wide variety of attractive and serviceable finishes.
The metal is heated to pouring temperature in separate holding furnaces and transferred to the shot cylinder by ladling. The metal injection chamber is separated from the melting pot and is not heated to the melting temperature of the alloy. These machines are also called plunger casting machines.
Die castings are among the highest volume, mass-produced items manufactured by the metalworking indus-
These cold chamber machines are subdivided into two types based on the position of the injection chamber as
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Advanced Research Journals of Science and Technology
Horizontal cold chamber machines. Vertical cold chamber machines.
CAVITY2
SIDE INSERT CAD/CAM IN DIE DESIGN In the die casting scenario the advent of digital computers has facilitated the improvement of productivity and elimination of costly rework. Here before the physical realization of the die, the design can be redefined and the parameters can be decided which would yield good results. Variety of feed systems and combination of ideas can be selected. This is an analytic approach to estimate the validity of the design. Thus it gives enormous confidence to the designer even before the tool is manufactured. CAM The CAM portion of computer aided design and manufacturing is somewhat mature than CAD graphics. Computerized numerical control (CNC) of milling machines is quickly becoming common place and permits far more accurate tolerances than with manual milling. Programmed through punched tape, CNC machines follow computer controlled machine paths with upto five axis milling and automatic cutter changing capabilities. The latest technological stride in computerized machining involves dispensing with punched tapes altogether. “Distributed� CNC employs a coaxial cable between main frame computer and CNC milling machine to control cutter paths from the computer memory.
TOTAL ASSEMBLY OF DIE
CAVITY1
COMPUTER AIDED MANUFACTURING IN PRO/ENGINEER By using the fundamental abilities of the software with regards to the single data source principle, it provided a rich set of tools in the manufacturing environment in the form of tooling design and simulated CNC machining and output. Tooling options cover specialty tools for molding, die-casting and progressive tooling design. Manufacturing lets you set up and run NC machines, create assembly process sequences, create bills of material,
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Advanced Research Journals of Science and Technology
and generate inspection programs for Coordinate Measuring Machines (CMMs). Use the Manufacturing area is about streamlining the NC programming process for production milling of prismatic parts and multisurface three-axis milling. Manufacturing shows you how to program and set up your NC machines, create process flows that cover the NC operations as well as other operations, and define CMM inspection programs that probe manufactured parts. PROCEDURE OF MANUFACTURING Cavity
NC Program for roughing % G71 O0001 N0010T1M06 S5500M03 G00X-66.809Y-8. G43Z5.H01 Z2. G01Y-86.96 G02X-49.666Y-85.46I7.426J-.002 X-49.819Y-83.96I7.262J1.5 G01Y-80.51 X-50.096 Z5. M30 % For finishing
Tool path
NC check NC Program for Finishing % G71 O0002 N0010T1M06 S2347M03 G00X-133.853Y-116.832 G43Z5.H01 Z-50.849 G01Z-51.349F1500. X-105.448Y-96.486 X-105.191Y-96.265 X-105.155Y-96.248 X-104.574Y-95.764 X-104.537Y-95.746 X-103.849Y-95.187 Z5. M30 % 4
Advanced Research Journals of Science and Technology
CONCLUSION In our project we have modeled a cylinder fin body for 150cc engine and die set for manufacturing. In the next step we have done Die calculations for the casting tool. From the above caliculations we have prepared the mould set parts and prepared core and cavity using pro/engineer. Total force acting on the die plate is 88.09Tons. So we selected 250Tons Machine. Plunger dia is 98mm and shot volume is 9.2kg. Fill time for magnesium is 0.665secs and heat to be removed is 2069.052cm3/sec. Fill time for Aluminum is 0.182secs and heat to be removed is 7560 cm3/sec. We have done manufacturing processes for the two cavities and side insert and generated CNC Program. We conclude that we can produce megnisium and aluinium fin bodys on the same mould by modifying cooling chanels without any additional investment.
[2]Myung-Rae,Dae-Yoon, and S.Hyuk, “Load Characteristics of Engine Main Bearing Comparison Between Theory and Experiment,” KSME International JournalVol. 16, pp.1095-1101, 2002. [3]Z. P, Mourelatos, “A crankshaft system model for structural dynamic analysis of internal combustion engines,” Combustion and enginesvol. 79pp. 2009-2027, 2001. [4]O kamura. Experimental study of the correction between crankshaft vibrations, engine structure vibrations, and engine noise in high speed engines. SAE Paper, 951290, 1995
AUTHOR S.C.Jung , , Research Scholar, Department of Mechanical Engineering, SR. Engineer, china. R. Ohmi Professor , Department of Mechanical Engineering, SR. Engineer, china.
REFERENCES [1]J. Haats and S. Wambach, “Lightweight crankshaft drives by forging,” Steel times, pp. 346-347, september 1999
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