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Principles of Operation:

Gear type pumps are ideal when working with pressures up to 1500 lb./sq.in. As mentioned previously, the volumetric efficiency of gear pumps depends upon the number of teeth, the engine speed and the tooth area.
As the liquid comes from the reservoir, it is pushed between the gear teeth. The oil is moved around to the other side by the action of the drive gear itself and sent through the pressure line. What makes the oil squeeze in between the gear teeth? gravity and the pressure head. To prevent leakage of oil from the high to the low pressure side from occurring, you can make the gears fit better. 
You might want to increase the pressure used to move the fluid along. However, the higher the pressure, the higher the friction loading on the teeth.
Friction will develop heat which will expand the gears and cause the pump to seize (parts will weld together and gears will stop rotating). In order to stop this, you can have the pump case, the gears, and the bearings made out of different materials, (e.g., steel gears [1-1/2 inch thick], bronze bearings, aluminum casing). Normally, the gear speed is higher than the engine speed (normally 1.4 times the engine speed). 
Oil can leak over and under the gears. To prevent leakage, you can press the bearings up against the gears. This decreases seepage but this decreases the mechanical efficiency when friction increases. Even though oil acts as lubricant, seizing can occur when oil is drained from the hydraulic system.
As mentioned previously we can push the bearing up against the gear to decrease leakage. As F increases, M decreases , thus, the gear and bushing increase in friction and mechanical efficiency decreases. when you increase the pressure on inlet side of the pump, leakage will increases around the gear. to reduce the leakage , you must push the bearing and gear closer, causing an increase in friction . that in why inlet pressure over 1500lb/sg, are not used.

Shell Moulding

    


Shell moulding is a process in which the sand mixed with a thermosetting resin is allowed to come in contact with a heated metallic plate, so that a thin and strong shell of mould is formed around the pattern. Then the shell is removed from the pattern and the cope and the drag are removed together and kept in a flask with the necessary backup material and molten metal is poured into the mould.

Hot Chamber Die Casting

    



Casting Process

Hot chamber Die casting, and
Cold chamber Die casting.               

The main difference between these two types is that in hot chamber, the holding furnace for the liquid metal is integral with the diecasting machine, whereas in the cold chamber machine, the metal is melted in a separate furnace and then poured into the diecasting machine with a laddle for each casting cycle which is also called ‘shot’.

Hot Chamber Process 

In this process, a gooseneck is used for pumping the liquid metal into the die cavity. The gooseneck is submerged into the holding furnace containing the molten metal. The gooseneck is made of grey, alloy or ductile iron or of cast steel. A plunger made of alloy cast iron, which is hydraulically operated moves up in the gooseneck to uncover the entry port for the entry of liquid metal into the gooseneck. The plunger can then develop the necessary pressure for forcing the metal into the die cavity. A nozzle at the end of the gooseneck is kept in close contact with the sprue located in the cover die.

The cycle starts with the closing of the die when the plunger is in the highest position in the gooseneck, thus facilitating the filling of the gooseneck by the liquid metal. The plunger then starts moving down to force the metal in the gooseneck to be injected into the die cavity. The metal is then held at the same pressure till it is solidified. The die is opened, and any cores if present, are also retracted. The plunger then moves back returning the unused liquid metal to the gooseneck. The casting, which is in the ejector die, is now ejected and at the same time the plunger uncovers the filling hole, letting the liquid metal from the furnace to enter the gooseneck.

 Air pressure required for injecting the metal into the die is that of the order of 30-45 kg/cm2. Depending upon its size, this hot chamber die casting machine can produce about 60 or more castings upto 20 kg each per hour and several hundred castings per hour for single impression castings weighing a few grams.

 Advantages of Die Casting Process

1  Very high rate of production can be achieved.
2  close dimension of tolerance of the order of ±  0.025 mm is possible.
3  Surface finish of 0.8 micron is achievable.
4  Very thin sections of the order of 0.50 mm can be cast.
5  Fine details may be produced.
6  Less floor space is required.
7  Longer die life is obtained.

Disadvantages of Die Casting Process

 1  Not economical for small runs.
2  Only economical for non-ferrous alloys.
3  Cost of die and die casting equipment is high.
4  Heavy castings cannot be cast. In fact, the size of the dies and the capacity of the die casting machines available limit the maximum size.
5  Die castings usually contain some porosity due to entrapped air 

Applications

The typical products made by die casting are carburetors, crank cases, magnetos, handle bar housings, parts of scooters and motor cycles, zip fasteners, head lamp bezels, and other decorative automobile items.

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Cold Chamber Die Casting

    


Cold Chamber Die Casting Process

The hot chamber process is used for most of the low melting temperature alloys such as zinc, lead and tin. For materials such as aluminum and brass, their high melting temperatures make it difficult to cast them by hot chamber process, because gooseneck of the hot chamber machine is continuously in contact with the molten metal. Also liquid aluminum would attack the gooseneck material and thus hot chamber process is not used with aluminum alloys. In the cold chamber process, the molten metal is poured with a ladle into the hot chamber for every shot. This process reduces the contact time between the liquid metal and the hot chamber.

The operation starts with the spraying of die lubricants throughout the die cavity and closing the die when molten metal is ladled into the hot chamber of the machine either manually or by means of an auto ladle. An auto ladle is a form of robotic device, which automatically scoops molten aluminum from the holding furnace and pours it into the die at the exact instance when required in the casting cycle. The pouring temperature can be precisely controlled with the help of auto ladle and hence the desired casting quality can be had. Then the plunger forces the metal into the die cavity and maintains the pressure till it solidifies. In the next step, the die opens.  The casting is ejected. At the same time, plunger returns to its position completing the operation.



Cold chamber and hot chamber die casting differs from each other in the following respects :

Melting unit is not an integral part of the cold chamber die casting machine. Molten metal is brought and poured into the die casting machine with the help of ladles.
In case of cold chamber process high pressures tend to increase the fluidity of molten metal possessing relatively lower temperature and hence castings produced are denser, dimensionally accurate and free from blowholes.
In case of cold chamber process die components experience less thermal stresses due to lower temperature of the molten metal. However, dies are required to be made stronger in order to bear high pressures.
Cold chamber process has a longer cycle time compared to hot chamber process.
In case of cold chamber process as metal is ladled from a furnace, it may loose superheat and may cause defects such as cold shuts. 


Air Bearing

    


What Is An Air Bearing?

An air bearing is a device, usually made from a rubber-type fabric, that is designed to inflate with compressed air and forms a floating action above the floor surface it is sitting on.

Incorporated into an air caster load module, the air bearing is then used, with others in a series of three or more, to simultaneously float heavy loads away from the floor surface on a thin film of air thus allowing the loads to be floated similar to a hovercraft to a new destination.

How Do Air Bearings Work?

Air bearings are designed to lift loads away from the floor surface and float them off to their destination on a thin film of air. Each individual air bearing is housed in a load module which contains an air flow control valve to regulate the operation of that air bearing.

When compressed air is introduced into the air bearing, the bearing initially inflates to form a seal between the bearing and the floor surface. As the air bearing is further pressurized it is forced to expel compressed air from the exhaust holes in the air bearing diaphragm. The force of this expelled air against the floor surface causes the air bearing and load module to lift off the floor on a thin film of air. The load should now be in flotation mode and ready for action.

Do Air Bearings Work Individually?

No. Air bearings need to be coupled with other air bearings, in sets of three or more, to form a system that can handle an appropriate load. An individual air bearing is not able to balance a load on its own - it will tip easily -  nor is it capable of being adjusted to accommodate variations in load weight and irregular shape. The strength of air bearing lifting power becomes apparent when they are grouped together and their collective lifting abilities are combined to offer some formidable lifting capacities.

When air bearings are grouped together to form an air bearing system, they then offer some real lifting power. The beauty of using air bearings in groups of three or more is that they can be individually adjusted to suit the properties of the load they are carrying.



Where Does The Air Plug Into The Air Bearing?

Compressed air is introduced into an air bearing system in one of two ways:

If the air bearing is part of a manually operated system, (no remote control unit) then each load module will contain an air flow control valve on one of its edges. This air flow control valve can be used to control an individual air bearing by increasing or decreasing the amount of air being applied to the bearing.

If the air bearing is being used as part of a remote controlled system, the load module will have an air inlet port on one of its edges. This port accepts an air supply hose, fitted with quick disconnects, which runs to an air outlet port from the remote control unit. Air flow control to the bearing is controlled from the remote control unit.
Where Does the Shop Compressed Air Supply Connect?

Air bearing systems are powered by regular compressed air that runs around most industrial facilities.
All of our systems and air other powered products have an air inlet port, or flow control manifold, to connect the shop compressed air supply to.

In the case of air bearing systems using, say, a four or six station setup, the shop compressed air supply would connect directly to an air flow control manifold. An on/off ball valve on the manifold then controls the air flow to the air flow control valves on each load module. Individual air bearing control is then applied at the air flow control valves
.
In the case of air bearing systems that are controlled via remote control, the shop compressed air supply is connected directly to the inlet port of the remote control unit. The remote control unit then controls the air flow to each individual load module and air bearing.

What Minimum Air Pressure Should My Shop Supply Be?

On a standard air bearing system using regular A-type air bearings the required minimum air pressure from the shop supply should be 70 psi.

On air bearing systems using B-type air bearings the minimum required air pressure from the shop supply should be 70 psi.

The volume of air required will differ depending on the floor surface, the weight of the load, and the type of bearing being used. All air requirements will be explained to you at the time of order.

Here are the main options to choose from:

A-type Air Bearings:

A-type air bearings cause their loads to lift away from the floor surface just enough to allow them to be floated off to the destination. A-type air bearings when use in series of four or more are capable of lifting and moving loads of up to 100 tons and beyond.

B-type Air Bearings:

B-type air bearings are a high-lift bearing which, when energized, cause the load to lift vertically away from the floor surface as much as 3 inches, depending on the type of bearing being used. These bearings are used when vertical lift is required before floating the load away. Such loads could be dropped on low level custom-pallets or racking. B-type air bearings when use in series of four or more are capable of lifting and moving loads of up to 100 tons and beyond.


What Is A Load Module Or Air Caster?

A load module or air caster is a machined assembly - either lightweight aluminum or steel - that houses an air bearing.

Load modules - also known as air casters - are available for each size of air bearing.

Load modules are fitted with inlet ports, or air flow control valves, and contain air chambers that allow air to flow from the inlet to the air bearing to cause pressurization and eventual flotation to take place.

Shown to the right is a typical square aluminum air caster module. The yellow part is the actual air caster load module and the black inner section is the air bearing assembly

How Is A Load Module Or Air Caster Used?

Load modules - also known as air casters - are used primarily to house individual air bearings and their load pads to make them ready for operation. An air bearing cannot work on its own. It needs a load module to cause it to receive compressed air, pressurize, and float away from the floor surface.


Load modules are used in multiples of three and more and are flexible in that they can usually form a footprint of the load to be moved, and have the load applied directly on the modules and then floated off to their destination.
.
Shown to the right is a typical air caster module footprint layout showing a four-module system complete with air supply hose and tee-piece fittings back to the shop air supply.

Seminar Topics

    


   ID
Seminar Topics of Mechanical And Automobile Engineering
1
Safety Air Bags in Cars
2
Hero-Honda Joint Venture
3
Manually Operated Sheet Metal Bending Machine
4
Ceramic Disc Brakes
5
Under Water Welding
6
Fuel Dilution
7
Steel Melting Shop
8
Orbital Welding
9
CNC Machine
10
Hybrid Design Electrothermal Polymeric Microgripper with Integrated Force Sensor
11
Modelling and Validation of a Truck Cooling System
12
Green Engine Technology
13
Automatic Air Suspension System
14
CAD & CAE IN BIOMEDICAL FIELD
15
Alcohol as an Alternative Fuel in I.C. Engines
16
Helicopter Aerodynamics
17
A Double Claw Robotic End Effector
18
Magnetic Nano Composite Materials for High Temperature Applications
19
Ball Piston Engine
20
The New Smart Eraser Design
21
Bio-Diesel
22
Steam Turbine
23
Stealth Aircraft Technology
24
Space Robotics
25
Rotary Engine
26
Skybus
27
Aerodynamics In Cars
28
Electromechanical Human Machine Interactions
29
Laser Ignition For Combustion Engines
30
Steam Power Robot
31
Water Jet Cutting
32
Wind Power Generation
33
Gas Turbine Blade Cooling
34
Nuclear Reactor
35
Variable Valve Timing Modification
36
Air Ride Suspension
37
Vacuum Brake System and Modification
38
Optimization of Machining Techniques in CNC Turning Centre Using Genetic Algorithm
39
Nano IC Engine
40
Mercedes Benz F125 Hydrogen Vehiclde
41
Ocean Thermal Energy Conversion
42
Introduction of Transfer Machine
43
Quasi Turbine
44
Hexapod Robots
45
Exhaust Gas Recirculation
46
Hybrid Fuel Cell Electric Vehicles
47
Fractal Robots
48
Solar Power Air Conditioning
49
Alternative Energy Sources for Fossil Fuels
50
Aluminium Alloys for Automotive Structures
51
Electro Hydraulic Brake (EHB) System
52
New Trends In Automobiles
53
Reverse Engineering
54
Biomechatronic Hands
55
Four Wheel Steering
56
Ultrasonic Welding
57
Quasi Turbines : The Advanced Rotary Combustion Engine
58
Computer Integrated Manufacturing
59
Fabrication and Performance Evaluation of the Solar Still
60
Military Radar
61
Design And Optimization Of Ambassador Car Leaf Spring Using Finite Element Analysis
62
How to Increase Fuel Efficiency of Car
63
Stress Analysis On 500mw And Newly Designed 800mw Swing Valve - Project
64
Double Pipe Heat Exchangers
65
Energy Conservation in Air Compressor
66
Flexible Manufacturing System
67
Composite Materials for Innovations Wind Turbine Blade
68
Complete Automotive Safety
69
Flux Core Arc Welding
70
Automobile Ignition System
71
Smartronics Intelligent Vehicle Stability System
72
DTS-SI System
73
Power Generation From Road Speed Breaker And From Shoes
74
Direction Control Valve
75
Synthesis of Carbon Nanotubes Using Nanotechnology
76
Camless Engine
77
Virtual Manufacturing
78
Smart Dust Core Architecture
79
Leser Beam Machining
80
Ballpoint Pen
81
Hybrid Vehical
82
Smart Materials - A view towards Shape Memory Alloy
83
Air Muscle
84
Laser Cutting
85
Nano Robotics
86
Gasoline Direct Injection
87
Magnetic Bearings
88
Automatic Gear Shift Mechanism
89
Six Stroke Engine
90
Plastic Injection Molding
91
CAM and Follower
92
Apache Helicopter
93
Aircraft System
94
Steam Power Plant
95
Fulcrick Wheel
96
Flying Car
97
Abrasive Jet Machining
98
Automatic Gear Transmission
99
Solar Assist Electrical Vehicle
100
Auto Turning Fuel Valve
101
Valvetronic Engine
102
Thermo Acoustic Refrigeration
103
Blast Furnance
104
Fuel From Plastic Waste
105
Hovercraft
106
Nitro Shock Absorber
107
Free Flow Exhaust System
108
Magnetics Levitation
109
Clever Three Wheeler Vehicle
110
Hydrogen Wire Car
111
Alternative Fuels
112
Electric Bicycle
113
Plasma Spray Coating Method
114
Air Car
115
Common Rail Diesel Injection
116
Aerodynamic Car
117
Ultrasonic Motors
118
High Speed Trains
119
Automotive Noise and Vibration Control
120
Automatic Control of Cars
121
3D Printing
122
Active Suspension System
123
Fuel Energizer
124
Concept Types and Application of Six Stroke Engine
125
Stealth
126
Robot Welding
127
Turbofan Engine
128
Driverless Car
129
Light Weight Material-Carbon Fibre
130
Resource Conservation
131
Pistonless Pump For Rocket
132
Hyper Transport
133
NTPC limited
134
Lean Six Sigma
135
Floating Solar Chimney Technology
136
Gas Welding
137
Rocket Proppellant
138
Nano Cars In The Robotics
139
Green Manufacturing
140
An Introduction To Motor Vehicles Act
141
Micro Turbine Generators
142
Automatic Braking System Control
143
Emission Standards For Light And Heavy Vehicles
144
Robots in Industrial Automation
145
Boiler Operation
146
Hydrodrive
147
Maglev Levitation Trains
148
Stratified Charge Engine
149
Magneto Abrasive Flow Machining
150
Hydro Forming
151
Automated Highway Systems
152
Valvetronic Engine Technology
153
Automatic Transmission System
154
Fiber Bragg Grating Technologies
155
Air Bearing
156
Car Speed Control by Blue Tooth
157
Robotic Surgery
158
Continuously Variable Transmission
159
Cryogenic Grinding
160
Regenerative Braking System
161
Electronic Fuel Injection System
162
Nuclear Battery
163
Nickel Titanium
164
3D Machine vision Systems
165
Vbration Analysis
166
Free Piston Engine
167
Rapid Prototyping Technology
168
Heat Transfer Through Nanofluids
169
Cylinder Deactivation
170
Supercavitation
171
Friction Stir Welding
172
Automated Orbital Welding Systems Streamline
173
Smart Materials
174
Thermal Barrier Coatings on IC Engines
175
Oil Mist Lubrication
176
Common Rail Fuel System and Exhaust Valve Control
177
Advanced Fine Finishing Processes
178
Solar Wind Hybrid System
179
Boiler Instrumentation Control.
180
Cryogenics and its Space Applications
181
Low Pressure Thermocompressor
182
Under Water Windmill
183
Solar Power Satellites
184
Multi Point Fuel Injection System
185
Micromachining
186
Dyna Cam Engine
187
Thermal Barrier
188
CO Generation
189
Torque Converters
190
Nano Robot In Human Body
191
i-VTEC and Electronic Lift Control
192
Automated Guided Vehicle System
193
Air Powered Car
194
Surface Plasmon Resonance
195
Power Steering
196
Carbon Nanotube: A Future Materials
197
Casting Process Design Guidelines
198
Non Destructive Testing
199
Mechanical Governor
200
Saab Combustion Control
201
Fins With Different Cross Sections
202
Lasers Induction Ignition Of Gasoline Engine
203
Laser Guided Missiles
204
MHD Power Generation
205
Fuel From Waste Plastic
206
Supercharger
207
Pico-Hydro Power Plant
208
Solar Tracking System
209
Antimatter
210
Steel Plant
211
Braking System
212
Air Intake System
213
Boilers Design
214
Air Craft Hydraulic System
215
Laser Ignition System
216
Application In Nitrous Oxide In Automobile
217
Autonomous Parallel Parking RC Car
218
Temparature Control Of Vaccum Brazing Furnace Using PLC
219
Fabrication and Testing of Composite Leaf Spring
220
Casting Process
221
Combustion Stability in I.C.Engines
222
Robotics and its Applications
223
CRDi System
224
Disel Engine Nox Reduction
225
Backhoe Loaders
226
Electric Power Assisted Steering
227
Scramjet Engine
228
Round Engine
229
Truck Tyre Basics
230
Four Wheels Steering
231
Plasma arc welding And Machining
232
Mannual Transmission System
233
Manufacture Of Portland Cement
234
Cryogenic Treatment of Brake Rotors
235
Microscopic Friction
236
Tools for Improving Machine Tool Volumetric Accuracy
237
Future Cars
238
Lean Manufacturing
239
Ejection Seat
240
Active Magnetic Bearing
241
Cryocar
242
CNC-Computer Numerical Control
243
Cruise Missile Technology
244
Automatic Dam Doors Control by Using Centrifugal Governor System
245
Self Inflating Tyres System
246
Sensotronic Brake Control
247
Methanol Fueled Marine Diesel Engine
248
Air Powered Engine
249
Google Driverless Car
250
Hydrogen Vehicles : Fuel of the Future
251
Frost Free Heat Exchanger
252
Determining the Recycling Rate of a Work Machine
253
Cryogenic Engine In Rocket Propulsion
254
Brain Controlled Car For Disabled Using Artificial Intelligence
255
IVTEC Engine
256
Manufacturing of Ball Bearing
257
Night Vision System
258
Automatic Screw Jack
259
High Speed Machining
260
DTS-I Technology
261
Automatic Street Light Powered Through Speed Breaker - Project
262
Biofuels as Blending Components
263
Solar Energy Car
264
Ceramic Cutting Tool
265
Design and Fabrication of a Tension less bike
266
Coal Gasification
267
Anti Lock Braking System
268
Dimethyl ether-an Alternative Fuel
269
Biodiesel Production from Waste Chicken Fat

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