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Engineering and technology index

 

 

Engineering design glossary

Engineering environmental glossary

Engineering general glossary

Engineering technical terms and abbreviation

Gears

Materials properties density

Materials properties hardness

Power diodes

Power electronics

Soldering brazing and welding

Steel fittings and flanges terms

work in progress ..

 

Coming soon:

 

Definition of heat power, definition of thermodynamics

Sources of energy used in heat power – a) coal, b) oil, c) gases
Development of Heat engines (brief discussion) – a) external combustion engines, b) internal combustion engines
Fundamental concept – system – boundary – surrounding a) closed system, b) open system, c) isolated system, flow system , non-flow system
State of a system – properties – intrinsic and extrinsic properties
Path - process
Equilibrium – a) Mechanical, b) Thermal, c) Chemical, d) Thermodynamic equilibrium.
Cycle – Thermodynamic cycle, Mechanical cycle
Units – Absolute & gravitational system of units – a) S.I. units, b) M.K.S. Gravitational units – Weight
Pressure – Definition, Units – S.I. and M.K.S. – Pascal, bar, torr – Kgf/cm2 standard atmospheric pressure – gauge pressure, absolute pressure – simple problems. 
Temperature - Definition, units – Zeroeth Las of Thermodynamics, Instruments used for measuring temperature.
Meaning of N.T.P. and S.T.P.
Work – Definition of work from thermodynamic point of view  - representation of work on P-V diagram   and units
Power – Definition – KW and HP, relation between KW and HP
Energy – Definition – Stored energy – units i) Potential, ii) Kinetic, iii) Internal energy – b) transitional energy – Heat and Work.
Flow work or energy of flow
Heat - Definitions and units – similarities between heat and work
Specific heat at constant pressure (Cp) and Specific heat at constant volume (Cv), Adiabatic Index (Cp/Cv)
Enthalpy
First Law of thermodynamics - Mechanical equivalent of heat, - perpetual motion machine of first kind (PMMI)
General Energy - equation for steady flow system and associated energy terms – S.F.E.E. – applicable to  - a) nozzle, b) boiler, c) steam turbine, d) compressor (No Problem)
Simple energy equation for non-flow process ( Q – W) =  E
Limitation of 1st. Law of thermodynamics – a) heat engine and b) heat pump – efficiency of heat engine, C.O.P. and E.P.R.
2nd law of thermodynamics – statement (Clausius & Kelvin-Planck)
Perpetual motion M/c of 2nd (PMM-II)

 

Properties of Gases                                                                                                    

      Difference between gas and vapour – critical temperature and pressure, difference between perfect gas and real gas

      Equation of state – PV = MRT - characteristic gas constant – units, Physical significance of characteristic gas constant – universal gas constant.

      Relation between two Specific heats with characteristic gas constant.

      Entropy – concept – analogy of heat energy with work – concept of T – Q plane – units of entropy. Entropy change of a perfect gas in terms of  a) T – V , b) P – V and c) P and T.

      Non-flow process of perfect gas, P-V and T-Q diagram, relation between pressure and temperature, volume and work done , change of I.E., heat transfer, change of entropy for the following processes

      Isochoric  process

      Isobaric process

      Isothermal process

      Adiabatic process

      Polytropic process

      Problems on processes

       

      Steam                                                                                                                              

              Formation of steam, change of state, T-S diagram

              Basic terms and properties of steam: Saturation temperature, saturation pressure, dry, wet and superheated steam, dryness fraction, degree of superheat, sensible heat or liquid enthalpy, enthalpy of evaporation or latent heat of evaporation, enthalpy of dry saturated, wet, superheated steam, specific volume, entropy of water, evaporation and steam (dry, wet & superheated)

              Throttling of steam (concept only)

              Steam table – its use, problems using steam tables

              Enthalpy- Entropy chart (Mollier – chart) – its use

              Steam calorimeters, types, principle for calculation of dryness fraction in:

              throttling calorimeter

              separating and combined calorimeter

               

              Machine tool

              Metal cutting machine tools – definitions, classifications, elements, purpose and accuracy

              Machine tool drives – elements, classifications, individual vs group drive

              Metal cutting                                                                                                                

              Cutting tools materials – Properties and uses – Cutting tool life – Equation for cutting tool life – Factors for cutting tool life.

              Cutting tool classifications, nomenclature of a single point cutting tool, tool angles and its       influence

              Forces acting on a single point cutting tool, orthogonal and oblique cutting

              Concept of chip formation, types of chips

              Coolant used in metal cutting

               

              CLASSIFICATION OF STEEL                                                                                                    

              a) Carbon steel – Dead steel, mild steel, medium carbon steel, high carbon steel, percentage of carbon & application of each . Influence of manganese, silicon,  sulpher, & phosphorous in  plain carbon steel.

              Alloy steel – Purpose of using alloy steel ,effects of alloying elements like nickel, chromium, cobalt, manganese, silicon, molybdenum, tungsten , vanadium , Classification of alloy steel according to the principle alloying elements , names & uses , Classification of alloy steel according to purpose & application- structural steel , tool steel – composition & application

               

              IRON CARBON EQULIBRIUM DIAGRAM & HEAT TREATMENT OF STEEL                     

                Iron carbon diagram – Name of the phases & temperature of transformation to be specified ( without going  into detail of any structure)

                Concept of heat treatment of steel & purpose of heat treatment

                Annealing , normalising , hardening , tempering of steel , principle of the process ( heating temp. ,soaking , cooling ) , purposes & uses of each process ,hardenability , definition & tests

                Case hardening process – a)Curburising b) Nitrading c) cyaniding – principle , purpose & uses

                Surface hardening – a) Flame hardening b) Induction hardening – principle & purposes

       

       

      Welding & Allied Process                                                                                      

          Concepts of welding - Workability

          Gas Welding: Principle, Equipments, Types of flames, Application, Safety — Arc Welding: Principle, Application, equipment, safety.

          Resistance Welding: Types (Names Only) — Spot Welding: Principle, simple sketch of setup, application — Seam Welding: Principle, simple sketch of setup, application.

          Thermit Welding: Principle of operation, application

          Special Welding Techniques: TIG, MIG, Electron Beam Welding, sub-merged arc welding – Principle & Application

          Defects in welding, Remedies

          Soldering, Brazing – Principle and application.

       

      Mechanical Working of Metal                                                                                

            Classification of mechanical working of metals – Hot working and Cold working – examples.

            Forging – Types (Hand forging, Power hammer forging, Drop forging, Press forging) – Principle of operation – Characteristics, Advantages and Defects of forged parts – Application.

            Extrusion – Definition, Principle of operation, Hot and Cold extrusion, Application

            Rolling - Principle of Hot and Cold rolling – Field of application

            Wire drawing – Principle of operation, Field of application.

             

                    Mechanical and chemical cleaning of metals (Names & Principles)

                    Surface Treatment – Electroplating, Hot Dipping, Metal Sprays, Anodising, Enamelling, Galvanising (Principle and field of application)

             

       

Steam Power Cycles                                                                                                     

Reversible Cycle – Carnot Cycle (with gas and vapour) – Representation on P-V, T-S planes, Thermal Efficiency – impracticability of Carnot Cycle in active cases – (Problems on Carnot Cycle with steam). Rankin Cycle – with & without feed pump work. P-V, T-S diagram, Thermal Efficiency, Work Ratio, Specific Steam Consumption, (Problems), Modified Rankine Cycle – P-V, T-S diagram, (Simple line diagram & Names – No details) (No Problems), Simple Reheat Cycle – Regenerative Cycle (No Problem)

 

Heat Transfer                                                                                                                

Three Basic Modes of Heat Transfer

Conduction: Fourier’s Law of heat conduction – Thermal Conductivity.

Heat transfer through plane homogeneous wall, Heat transfer through composite wall, Heat transfer through hollow cylinder – (Simple Problem)

Convection: Explanation of Convective heat transfer, Principle of heat exchanger (No Deduction & Problem)

Radiation: Explanation of heat transfer by radiation, definition of absorptivity reflectivity, transmissivity, Black Body. Stephen-Boltzman Law – Statement and Explanation of terms with unit (No Problem)

Steam-power plant lay-out

 

Shaper & Planner                                                                                               

Specifications & types of Shaper

Construction of a Shaper & brief functions of its part.

Crank slotted link mechanism (adjustment of length of stroke & position of stroke).

Hydraulic shaper -Working principle & quick return mechanism.

Different operation performed on a shaper –Flat surface, Angular surface, Slot, Formed surface.

Cutting speed, feed, depth of cut machining time calculation.

Cutting tool - types only.

Job holdings devices – Fixture, Vice, Directly over table.

Planning m/c- Specifications & types. Quick return mechanism a) Open & Cross belt b) Variable speed.

Difference between Planner & Shaper.

 

Milling Machine                                                                                                         

Types specification.

Difference between plain milling & universal milling.

Milling m/c parts & their functions.

Cutter holding device – Arbors, fixing of arbor with machine spindle. Arbor assembly accessories & attachments.

Milling processes- Peripheral milling, Up & Down milling, difference, Face milling, End milling, Straddle milling, Plain milling, Side milling, Angular milling, Gang milling, End milling etc.

Milling operations with cutter & job set up & the directions of movements.

Milling cutters- Types, elements, negative rake cutter (purpose).

Cutting speed, feed, depth of cut & machining calculations.

Indexing- Purpose, types, description with working principle of differential indexing head, cutting spur gear with different index head, calculation & problem, difference index plate & cutter nos.

Generating method of cutting gears – working principle of gear shaper, hob cutting.

 

Grinding Machine                                                                                                  

Abrasives – Types & Uses.

Effect of bond, Grit, Grade & Structure in manufacturing a grinding wheel.

Specification of a grinding wheel.

Grinding Machine – Types, Operations performed (specially Surface Grinding & Cylindrical Grinding) emphasis on Centreless Grinding (Outside & Inside)

Factors selecting a grinding wheel, Balancing & Mounting a grinding wheel, Glazing & Loading of   wheels. Care & Maintenance of grinding wheel.

Honning & Lapping – Principle & Use only.

Broaching Machine                                                                                                         

Advantage & disadvantage of using a Broaching machine.

Broaching Machine – Types, Operations performed, Accuracy achieved.

Broach tool – Elements, free hand sketch of a Broach tool.

Press Work                                                                                                                    

Types and size of a press machine.

Operations performed like Blanking, Piercing, Drawing, Bending, Embossing, Coining, etc.

Press tools (Die & Punch), Die accessories, elements of Die & Punch.

 

    Computer aided design process (Geometric Modelling, Engineering analysis,     Design review & Evaluation, Automated Drafting),

Benefits of CAD in Engineering industry                                                                                                                             

 

    Solar energy – Advantages & limitations

    Solar radiation – Extraterrestrial radiation, solar constant, atmoshpheric attenuation of solar radiation, beam, diffuse & total radiation

    Solar thermal collectors – Flat plate collector, its construction & operational features, advantages & limitations, concentrating collector, its principle of operation, advantages & disadvantages over FPC, solar pond, its construction & operational features, advantages & limitations

    Solar thermal power systems – Layout & description of low temperature system using FPC or solar pond, medium & high temperature systems using concentrating collectors, central receiver systems

    Photo voltic  power generation system – Layout, description & function of different elements, advantages & disadvantages

WIND POWER PLANTS                                                                                                 

    Wind energy – Planetary wind & local wind, wind power density, power coefficient, advantages & disadvantages of wind energy

    Wind power systems – Horizontal axis wind energy generator , its layout & schematic diagrams showing basic components & their functions, vertical axis wind mills, savonius & darrieus wind mills, their relative advantages & disadvantages

    Application of wind energy

GEOTHERMAL POWER PLANTS                                                                     

    Nature of geothermal fields

    Geothermal sources – Names of different sources, brief descriptions of various hydro thermal systems

    Geothermal power systems – Description with layout diagram of vapour dominated system, liquid dominated flashed system & binary systems, geothermal preheat hybid system

    Advantages & disadvantages of geothermal energy

    Application of geothermal energy

 

REFRIGERATION & AIR-CONDITIONING

 

    Terms and  defination – Heat engine, refrigerator, heat pump, refrigeration, refrigerant, refrigerating effect, refrigeration capacity, cop, relative cop

Methods of refrigeration ( names and application)              

AIR REFRIGERATION SYSTEM                                        

    Reversed carnot cycle, determination of cop

    Bell-Coleman cycle- open system, closed system. Determination of cop

                        ( problem)

    Boot- Strap air cycle- schematic and T-S diagrams. Necessity of aircraft cooling and sources of cooling loads.            

VAPOUR COMPRESSION REFRIGERATION SYSTEM                    

    Fundamental operations and analysis with schematic T-S and p-h diagrams for simple cycle , c.o.p

    Advantages and  disadvantages of  vapour compression system over air refrigeration system

    Actual vapour compression cycle—variation from theoretical cycle

     Effects of sub cooling and superheating

    Simple problems                                                      

VAPOUR ABSORPTION SYSTEM

    Flow diagram and operation of NH3- WATER cycle, components- generator,  rectifier, condenser, evaporator, absorber, heat exchanger, pump

     Flow diagram and operation of Lithium bromide – water cycle

     Flow diagram and operation of electrolux refrigerator

     Comparison between vapour compression and vapour absorption systems.

REFRIGERANTS

    Definition and function of refrigerant

     Desirable properties of refrigerant

     Classification of refrigerant

      Important requirements, secondary requirements

     Selection of refrigerant for required purpose                       

REFRIGERATION COMPONENTS, CONTROL AND SAFETY DEVICES

    Brief description and field of application of reciprocating  compressor, rotary compressor, centrifugal compressor

    Brief  description  and field of application of air cooled  and water cooled condensers

    Brief description and field of application  of evaporators

    Brief description  and field of application of expansion devices-capillary tube, thermostatic expansion valve

    Control and safety devices- low side float valve, high side float valve, solenoid valve, compressor over current and over heating protection, high and low pressure cut-outs                                 

 APPLICATION OF REFRIGERATION

    Food preservation- spoilage agents and their control, prservation by refrigeration

    Cold storage-construction ( layout), capacity and application

    Refrigerators and freezers

    Ice plant- construction (layout), capacity and application

    Ice- cream plant- construction (layout) and operational features

    Dry ice production- construction (layout) and operation of simple system, application

    Water cooler                   

     

      Air conditioning & its applications

      Industrial & comfort air conditioning, factors affecting human comfort, effective temperature, comfort chart, heat & moisture losses from human body

      Air conditioning systems – summer air conditioning for hot & dry climate, for hot & humid climate ( layout), winter air conditioning ( layout), all- air type & all- water type ( hydraulic ) air conditioning systems, unitary & central systems, all year air conditioning system ( layout) ,window air conditioner, split air conditioner, desert cooler & cooling tower

     

     

    COMPUTER AIDED DRAFTING

    Awareness of command ;- Limit, Zoom, pan, line, circle, polyline , multiline, polygon, arc, text, dtext, ddedit, dimension, hatch, layer, offset, trim, extend, erase, scale, dist, area, fillet, chamfer, array, block, attribute etc.   

    Assembly views  to be given . draw the Detail Drawing of the same through different sectional views ( Front View, Side View & Top View)

                                     

    FLUID MACHINES

     

    IMPACT OF JET.                                                                

      Direct impact of a jet on a stationary flat plate

      Direct impact of a jet on an inclined fixed plate

      Impact of a jet on a moving plate

      Impact of a jet on a series of flat vanes mounted on the periphery of a large wheel

      Condition fir maximum hydraulic efficiency

      Force of jet impinging on a fixed curved vane

      Force of jet impinging on a moving curved vane, velocity Diagram

      All related problems

    PUMPS            

      Reciprocating pump – Types

      Classification of pumps

      Working principle ( single acting & double acting), discharge, slip, pump work, power required, indicator diagram ( Simple related problems)

      Use of air vessels

      Advantages & disadvantages of reciprocating pump over reciprocating pump

      Centrifugal pump – types

      Working of the pump, methods of converting the K.E of water leaving the impeller into pr. Energy, the volute chamber, the vortex or the whirl pool chamber, guide blades, priming

      Inlet & outlet vector diagrams, work done by the impeller, the manometric head, the manometric effy., impeller power, the mechanical effy., the overall effy., (RELATED PROBLEMS)

      Minimum speed to run the pump. loss of head  due to reduced or increased flow ,multistage centrifugal pumps ,specific speed of centrifugal  pumps

      Selection of pump ( Both reciprocating & centrifugal)

    HYDRAULIC TURBINE                

      Classification – Impulse ,reaction & kaplan

      Pelton wheel – components , working principle, velocity diagrams, work done, power ,effy. ( PROBLEMS)

      Francis turbine – components, working principle, velocity diagrams, work done, power, effy., (PROBLEMS)

      Kaplan turbine- components

      Governing of an impulse turbine ( pelton wheel)

      Difference between impulse & reaction turbine

      Layout diagram of a hydraulic power house

      Selection of turbine – specific speed

    Draft tube
    MISCELLANEOUS      
    Hydraulic accumulator
    Fluid coupling
    Surge tank
    Water hammer ,Surge tank & Cavitation
    Intensifier

 

APPLIED MECHANICS AND DESIGN
Engineering Mechanics: Free body diagrams and equilibrium; trusses and frames; virtual work; kinematics and dynamics of particles and of rigid bodies in plane motion, including impulse and momentum (linear and angular) and energy formulations; impact.
Strength of Materials: Stress and strain, stress-strain relationship and elastic constants, Mohr’s circle for plane stress and plane strain, thin cylinders; shear force and bending moment diagrams; bending and shear stresses; deflection of beams; torsion of circular shafts; Euler’s theory of columns; strain energy methods; thermal stresses.
Theory of Machines: Displacement, velocity and acceleration analysis of plane mechanisms; dynamic analysis of slider-crank mechanism; gear trains; flywheels.

 

FLUID MECHANICS AND THERMAL SCIENCES
Fluid Mechanics: Fluid properties; fluid statics, manometry, buoyancy; control-volume analysis of mass, momentum and energy; fluid acceleration; differential equations of continuity and momentum; Bernoulli’s equation; viscous flow of incompressible fluids; boundary layer; elementary turbulent flow; flow through pipes, head losses in pipes, bends etc.
Heat-Transfer: Modes of heat transfer; one dimensional heat conduction, resistance concept, electrical analogy, unsteady heat conduction, fins; dimensionless parameters in free and forced convective heat transfer, various correlations for heat transfer in flow over flat plates and through pipes; thermal boundary layer; effect of turbulence; radiative heat transfer, black and grey surfaces, shape factors, network analysis; heat exchanger performance, LMTD and NTU methods.
Thermodynamics: Zeroth, First and Second laws of thermodynamics; thermodynamic system and processes; Carnot cycle. irreversibility and availability; behaviour of ideal and real gases, properties of pure substances, calculation of work and heat in ideal processes; analysis of thermodynamic cycles related to energy conversion.
Applications: Power Engineering: Steam Tables, Rankine, Brayton cycles with regeneration and reheat. I.C. Engines: air-standard Otto, Diesel cycles. Refrigeration and air-conditioning: Vapour refrigeration cycle, heat pumps, gas refrigeration, Reverse Brayton cycle; moist air: psychrometric chart, basic psychrometric processes. Turbomachinery: Pelton-wheel, Francis and Kaplan turbines — impulse and reaction principles, velocity diagrams.

 

Engineering Materials: Structure and properties of engineering materials, heat treatment, stressstrain diagrams for engineering materials.
Metal Casting: Design of patterns, moulds and cores; solidification and cooling; riser and gating design, design considerations.
Forming: Plastic deformation and yield criteria; fundamentals of hot and cold working processes; load estimation for bulk (forging, rolling, extrusion, drawing) and sheet (shearing, deep drawing, bending) metal forming processes; principles of powder metallurgy.
Joining: Physics of welding, brazing and soldering; adhesive bonding; design considerations in welding.
Machining and Machine Tool Operations: Mechanics of machining, single and multi-point cutting tools, tool geometry and materials, tool life and wear; economics of machining; principles of non-traditional machining processes; principles of work holding, principles of design of jigs and fixtures
Metrology and Inspection: Limits, fits and tolerances; linear and angular measurements; comparators; gauge design; interferometry; form and finish measurement; alignment and testing methods; tolerance analysis in manufacturing and assembly.

 

Theory of Machines
Kinematic and dynamic analysis of planar mechanisms. Cams, Gears and gear trains, Flywheels, Governors, Balancing of rigid rotors, Balancing of single and multicylinder engines, Linear vibration analysis of mechnical systems (single degree and two degrees of freedom), Critical speeds and whirling of shafts, Automatic Controls, Belts and chain drives. Hydrodynamic bearings.

 

Mechanics of Solids :
Stress and strain in two dimensions. Principal stresses and strains, Mohr’s construction, linear elastic materials, isotropy and an isotropy, Stress-strain relations, unlaxial loading, thermal stresses. Beams : Banding moment and shear force diagrams, bending stresses and deflection of beams, Shear stress distribution. Torsion of shafts, helical springs. Combined stresses, Thick and thin walled pressure vessels. Struls and columns, Strain energy concepts and theories of failure. Rotation discs. Shrink fits.

 

Enginerring Materials :
Basic concepts on structure of solids, Crystalline materials, Defects in crystalline materials, Alloys and binary phase diagrams, structure and properties of common engineering materials. Heat treatment of steels. Plastics, Ceramics and composite Materials, common applications of various materials.

 

Manufacturing Science :
Marchant’s force analysis, Taylor’s tool life equation, machinability and machining economics, Rigid, small and flexible automation, NC, CNC. Recent machining methods- EDM, ECM and ultrasonics. Application of lasers and plasmas, analysis of forming processes. High energy rate forming. Jigs, fixtures, tools and gauges, Inspection of length, position, profile and surface finish.

THERMODYNAMICS :
Basic concept. Open and closed systems, Applications of Thermodynamic Laws, Gas equations, Clapeyron equation, Availability, Irreversibility and Tds relations.

 

I.C. Engines, Fuels and Combustion :
Spark lgnition and compression ignition engines, Four stroke engine and Two stroke engines, mechanical, thermal and volumetric efficiency, Heat balance.
Combustion process in S.I. and C.I. engines, preignition detonation in S.I. engine Diesel knock in C.I. engine. Choice of engine fuels, Octance and Cetane retings. Alternate fuels Carburration and Fuel injection, Engine emissions and control. Solid, liquid and gaseous fuels, stoichometric air requirements and excess air factor, fuel gas analysis, higher and lower calorific values and their measurements.

 

HEAT TRANSFER, REFRIGERATION AND AIR CONDITIONING :
One and two dimensional heat conduction. Heat transfer from extended surfaces, heat transfer by forced and free convection. Heat exchangers. Fundamentals for diffusive and connective mass transfer, Radiation laws, heat exchange between black and non balck surfaces, Network Analysis. Heat pump refrigeration cycles and systems, Condensers, evaporators and expansion devices and controls. Properties and choice of refrigerant, Refrigeration Systems and components, psychometrics, comfort indices, cooling loading calculations, solar refrigeration.

 

 

 

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