Friday, 24 June 2016

Difference between Carnot Cycle and Rankine Cycle

Today I am going to tell you difference between Carnot cycle and Rankine cycle. Both Carnot cycle and Rankine cycle are air standard cycle. Carnot cycle is a ideal cycle of heat engine which gives highest efficiency between given temperature difference but it is a theoretical cycle and actually no engine works on Carnot cycle. Rankine cycle is ideal cycle of vapor or steam power generation. All steam power plant work on this cycle. It used water as the working substance. Both these cycle have different features which I will describe below.

Carnot cycle has two isothermal processes and two isentropic processes. Heat is added and rejected isothermally and compression and expansion take place at constant entropy. It is a theoretical cycle but actually it is difficult to achieve isothermal heat addition and rejection. It gives highest efficiency between given temperature difference. The efficiency of Carnot cycle is given by

As I told Rankine cycle is a ideal vapor power generation cycle used in steam turbine. It consist two isobaric and two isentropic processes. Heat is added and rejected at constant pressure and expansion and compression of gas take place isentropically. In practically first water is pumped to a boiler where heat is added at constant pressure which converts water into steam. This high temperature steam rotates the turbine. This expansion of gas takes places isentropically. Now the heat is rejected into condenser at constant pressure which converts it into water. Now the water is pumped isentropically which complete the cycle. This cycle runs continuously which generate power.

The basic and main difference between Carnot and Rankine cycle is that in Carnot cycle heat is added and rejected at constant pressure and in Rankine cycle heat addition and rejection take place at constant pressure. The other main difference is that the Rankine cycle use water as working substance and Carnot cycle used air as working substance. There are many other differences which are describe below in tabular form.

Difference between Carnot Cycle and Rankine Cycle

Difference between Carnot Cycle and Rankine cycle:


Sr. No.
Carnot Cycle
Rankine Cycle

1.

It is a theoretical cycle. . It gives maximum efficiency between two temperature difference


This one is a practical cycle of steam engine and turbine.

2.

Heat is added and rejected at constant temperature.


Heat is added and rejected at constant pressure.

3.

It has highest efficiency between two temperature differences.


Rankine cycle has lower efficiency than Carnot cycle.

4.

Carnot cycle uses air as the working substance.


Rankine cycle uses water as working substance.

5.

Carnot cycle is ideal cycle for heat engine.


It is ideal cycle for vapor power engine.

Today we have discussed about main difference between Carnot cycle and Rankine Cycle. If you have any query regarding this article, ask by commenting. 

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Wednesday, 22 June 2016

Difference Between Fan and Blower

The fan and blower are two different kind of machine belong to same group. Broth these machines are used to flow a gas or mostly air in a large area but the main difference between fan and blower is that the fan is operate at low pressure while blower is operate at high pressure.  These machines are used in many industrial machines for air conditioning or cooling purpose.

The fan consist a rotor witch is equipped with some blades. This rotor is rotate by a electric motor or sometimes by a mechanical machine. It is primary used to flow the air into a large space. Mostly fans used to blow the air axially or the direction of the air flow along the axis of the rotor. Fans blow large volume of air with minor change in pressure. It has specific pressure ratio is 1.1.

Blower is different from fan. It is a centrifugal unit which blows the air radially. It consist a impeller equipped with series of blades which are designed to flow air radially. It blow the air or gas with a moderate pressure change. The change in specific pressure ratio is 1.11 to 1.2.

Difference Between Fan and Blower

Difference between fan and blower:



S.No.


Fan

Blower

1.

The pressure change in fan is about 1.1


The change in pressure in blower is about 1.1 to 1.2

2.

It is used to flow of gas or air in open space.

It is mostly used to flow of gas in specific direction.

3.

It blows gases or air in every direction.


Blower is used to point the air in specific direction.

4.

It is smaller than blower.


Blowers are mostly larger than fan

5.

It consumes less energy.


It consist more energy.

6.

It does not have moving blades.


It may have moving blades to pointed air in specific direction.


Today we have learned about difference between fan and blower. If you have any query regarding this article, ask by commenting. 
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Monday, 20 June 2016

Difference Between Horsepower Vs Torque

Today we will discuss about difference between horsepower vs torque. These two terms are used to specify an engine or any rotary machine, but lot of people doesn’t know the accurate meaning of these both terms.  Horsepower and torque are very useful when you buy a vehicle of a rotary machine. Before discussing on this topic, first you should learn about the meaning of torque, horsepower and RPM. 

What are Torque, RPM and Horsepower?


Torque:

Torque is measure of rotary force. It is works as force works in linier motion. When a torque is applied on a shaft it rotates or tends to rotate if the torque is not sufficient. In simple words, the rotary force applied on a shaft to rotate it is known as torque.

In mathematically torque is the product of tangential force applied on a shaft and the radius of shaft. The SI unit of torque is N-m (Newton per meter).

Difference Between Horsepower Vs Torque

RPM:

RPM is the unit or measure of speed in rotary motion. The rpm is stand for rotation per minute. If a shaft rotate 50 cycle per minute mean it has 50 rpm speed. Larger rpm means larger speed.

Difference Between Horsepower Vs Torque

Horsepower:

Horsepower is the unit or measure of power. Power is the capacity of do work. Larger power means, more work can do in smaller time.

Mathematically work done per unit time is called power or product of force and velocity is called power. But in rotary motion Torque is stand for force and RPM for velocity so the product of torque and RPM is called power. The SI unit of power is Watt ( J/s). It is equal to the power needed to move 1N weight bar to one meter in one second. Watt is a very smaller unit so we used KW and Horsepower (HP) to specify a machine power. One horsepower is equal to the 735 Watt.

Difference Between Horsepower Vs Torque

Horsepower vs Torque:

As we know that horsepower is a unit or measure of power and torque is measure of force in rotary motion. In any rotary machine power is measured at highest rpm and the torque is at lowest rpm. If a vehicle is specified 400 HP @ 2000RPM means its maximum power is 400HP. If The same engine is specified as 2000 N-m @ 1300rpm means it give maximum torque is 2000 N-m.

The torque is measure of force applied to move the vehicle and the Horsepower is measure of rate of work done.

Torque plays a very important role while choosing a vehicle. Suppose two vehicles one is a truck and other one is a sports car. Both have same Horsepower 400 HP but both vehicles are with different each other. Sports car can't pull a heavy load like 1MT or a truck can't run on speed like 200Kph. The main difference between these machines is torque. A truck has a higher torque compare to sport vehicle so it can pull more load but due to power is function of product of torque and RPM so it has low RPM or speed. In the other hand the sport car has high RPM but low torque which gives it high speed. Both machines have same power but gives different uses.

It is seen like that a 1 kg block is move 10 meter or a 10 kg block is move one meter. Both have same power but have different pull force. These are key difference between them.

The more torque gives high starting power or gives more pickup to vehicle. So next time, when you go for buy a vehicle considered both Horsepower and torque and remember torque is pulling force and power means product of torque and RPM.

Today we have discussed about difference between horsepower vs torque. I think now you have better understanding between these. If you have any doubt regarding this article, ask by commenting.
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Friday, 3 June 2016

Difference between Hot Working and Cold Working

Today I am going to tell you main difference between hot working and cold working. They both are the metal forming processes. When plastic deformation of metal is carried out at temperature above the recrystallization temperature the process, the process is known as hot working. If this deformation is done below the recrystallization temperature the process is known as cold working. There are many other differences between these processes which are described as below.


Difference between Hot Working and Cold Working:



S.No.


Cold working

Hot working

1

It is done at a temperature below the recrystallization temperature.

Hot working is done at a temperature above recrystallization temperature.


2.

It is done below recrystallization temperature so it is accomplished by strain hardening.


Hardening due to plastic deformation is completely eliminated.

3.

Cold working decreases mechanical properties of metal like elongation, reduction of area and impact values.


It increases mechanical properties.

4.


Crystallization does not take place.

Crystallization takes place.


5.


Material is not uniform after this working.


Material is uniform thought.

6.


There is more risk of cracks.

There is less risk of cracks.

7.

Cold working increases ultimate tensile strength, yield point hardness and fatigue strength but decreases resistance to corrosion.


In hot working, ultimate tensile strength, yield point, corrosion resistance are unaffected.

8.

Internal and residual stresses are produced.

Internal and residual stresses are not produced.




These are the main difference between hot working and cold working. If you have any query regarding this article, ask by commenting. 
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Thursday, 26 May 2016

Milling Machine Operation

Today we will learn about milling machine operation. We have discussed about main parts and types of milling machine is my last post and know that milling is a most versatile machine used in mechanical industries. It can perform turning, facing, slot cutting, chamfering etc. to convert the work piece into desire shape. It can machine on both symmetrical and non symmetrical work piece. The various operation performed by milling machine are described below.


Milling machine operation:

As we know that milling can perform various operations to convert the work piece into desire shape. It is a very useful machine and mostly used in die making industries. The most popular operation done on milling machine is described below.

Plain milling:

As the name implies, this operation used to get place surface. In this milling, the cutting tool axis is parallel to the machining surface or the face of the machining surface. This operation is very common and done on almost all jobs. This can be carried out on every milling machine.

Milling Machine Operation

End milling:

This operation is also used to get plain surface. In this operation, the cutting tool axis is perpendicular to the machining surface or the face of the machining surface. It is also used to slot cutting on the milling axis.

Milling Machine Operation

Gang milling:

As the name is gang, in this milling operation more than one milling cutters are used to machining. It is a horizontal milling operation, more than one cutter with different shape and sizes are fixed at the arbor, which cut the desire shape in one pass. This milling operation can save most of time of milling.

Milling Machine Operation

Straddle milling:

In this operation, two or more parallel vertical surface machined in a single pass. In this milling the work piece is situated between the two cutters which can machined the surface vertically. The cutter are fixed on the same arbor and cut the metal in one pass.

Milling Machine Operation

Slotting:


In this operation slots are cut by a cutter on the work piece. The slots are in various shapes like circular, rectangular etc. and sizes according to the requirement. 

Milling Machine Operation

Angular milling:


In this operation, surfaces which are at an angle to the axis of the cutter, is machined by the rotary cutter.

Milling machine can perform all other common operations like turning, facing, fillet making, chamfering, drilling, gear cutting, planning, slot cutting etc. These are all main milling machine operation. If you have any query, ask by commenting. 
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Wednesday, 18 May 2016

Types of milling machine

Today we will learn about types of milling machine used in machining of metal work pieces. In my last post we have learn about milling machine and its main parts and we know that milling machine is one of the most versatile machine which can perform any machining operation on unsymmetrical work piece. It is mostly used in mold manufacturing. Due to its versatility, it is available milling machine available various types and sizes. These are described below.



Types of milling machine:

There are various milling machines are used in mechanical industries. These are described below.

1. Column and knee type milling machine:

It is the very common milling machine type. In this machine a vertical column is attached to the bed which consist all gear drives which rotate the knee and saddle. A knee is situated on the base which can provide vertical motion to the work piece or which can move up and down. A saddle is attached to the upper section of the knee which can move in transverse direction. The table is placed over the which can hold the work piece by use of climbing bolts.

Vertical milling machine:

In is one of the types of knee and column milling machine. The spindle if this machine is in vertical position. No arbor is required in this machine. The cutter tool has cylindrical shape and the cutting edges are situated at the circumference of the cylindrical face.

Types of milling machine

Horizontal milling machine:

As the name implies the spindle is situated horizontally. The spindle rotates horizontally. A arbor is attached to the machine which holds the cylindrical disk shape cutter which cuts the metal work piece.

Types of milling machine

Universal milling machine:

The universal milling machine is same as horizontal milling machine except there is a arrangement of swing up the table to 45 degree in either direction.

Types of milling machine



2. Fixed bed milling machine:

In this milling machine the bed of the machine is fixed to the machine. There is no arrangement of knee and saddle which can move vertically and transversally. The worktable is direct situated at the fixed bed. The spindle of this machine is mountain on a movable spindle head. It can move in vertical and horizontal direction and perform the cutting operation.

 Simplex milling machine:

In the simplex machine spindle head or the spindle can travel only in one direction. Mostly it travels in vertical direction.

Duplex milling machine:

In this machine the spindle can travel both in vertical and horizontal direction.

Triplex milling machine:

In triplex machine spindle can move in all three direction along X Y and Z axis.



3. Planner milling machine

Planner milling machine is mostly used for facing operation in mass production. These machine are similar to the bed type milling machine except it can mounted with various cutters and spindle heads to the machine. These cutters can perform the facing operations simultaneously.

Types of milling machine



4. Special milling machine:

These machines are the modern milling machines which are developed to easy the milling operations according to the jobs.

Tracer milling machine:

Tracer machine can perform all difficult die making job by synchronizing the tracing unit. It can develop any difficult shape. It is mostly used in automobile and aerospace industries.

CNC milling machine:

CNC is most versatile milling machine which is control by a computer. It is upgrade version of bed type milling machine in which the spindle can move in all three direction and the table can rotate 360 degree. These all movement is hydraulically controlled which is command by a computer. Any difficult geometry can make on it. A sketch of the work piece is loaded to the computer which is cut on work piece by the cutters automatically.

Types of milling machine

Image Source : www.indiamart.com

Today we have discussed about main types of milling machine. If you have any query regarding this article, ask by commenting.
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Tuesday, 17 May 2016

Gear Terminology: Basic Defination Used in Gear

Today we will discuss about gear terminology. Gears are widely used mechanical industries for power transmission. It is used where small distance between driver and driven shaft.  It is the only positive drive which can transfer exact velocity ratio to the driven shaft, so widely used in machineries and other mechanical devices. 

Gear terminology means all definitions used to describe a gear or the terms used to design a gear are known as gear terminology. The mostly used definitions are described below. 

Gear Terminology:


The following terms, which are mostly used to describe a gear, are as follow. 

Gear Terminology: Basic Defination Used in Gear

Face of tooth:

It is defined as the surface of the tooth above the pitch circle is known as face.

Flank of tooth:

The surface of the tooth below the pitch circle is known as flank.

Top land:

The top most surface of the tooth is known as the top land of the tooth.

Face width:

Width of the tooth is known as face width.

Pitch Circle:

It is an imaginary circle which is in pure rolling action. The motion of the gear is describe by the pitch circle motion.

Pitch Circle diameter:

The diameter of the pitch circle from the center of the gear is known as pitch circle diameter. The gear diameter is described by its pitch circle diameter. 

Pitch point:

When the two gears are in contact, the common point of both of pitch circle of meshing gears is known as pitch point. 

Pressure angle or angle of obliquity:

Pressure angle is the angle between common normal to the pitch circle to the common tangent to the pitch point. 

Addendum:

Distance between the pitch circle to the top of the tooth in radial direction is known as addendum.

Dedendum:

Distance between the pitch circle to the bottom of the tooth in radial direction, is known as dedendum of the gear.

Addendum circle:

The circle passes from the top of the tooth is known as addendum circle. This circle is concentric with pitch circle.

Dedendum circle:

The circle passes from the bottom of the tooth is known as dedendum circle. This circle is also concentric with pitch circle and addendum circle. 

Circular pitch:

The distance between a point of a tooth to the same point of the adjacent tooth, measured along circumference of the pitch circle is known as circular pitch. It is plays measure role in gear meshing. Two gears will mesh together correctly if and only they have same circular pitch. 

Diametrical pitch:

The ratio of the number of teeth to the diameter of pitch circle in millimeter is known as diametrical pitch. 

Module:

The ratio of the pitch circle diameter in millimeters to the total number of teeth is known as module. It is reciprocal of the diametrical pitch. 

Clearance:

When two gears are in meshing condition, the radial distance from top of a tooth of one gear to the bottom of the tooth of another gear is known as clearance. The circle passes from the top of the tooth in meshing condition is known as clearance angle. 

Total depth:

The sum of the addendum and dedendum of a gear is known as total depth. It is the distance between addendum circle to the dedendum circle measure along radial direction. 

Working depth:

The distance between addendum circle to the clearance circle measured along radial direction is known as working depth of the gear.

Tooth thickness:

Distance of the tooth measured along the circumference of the pitch circle is known as tooth thickness.

Tooth space:

Distance between the two adjacent tooth measured along the circumference of the pitch circle is known as the tooth space. 

Backlash:

It is the difference between the tooth thickness and the tooth space. It prevents jamming of the gears in meshing condition.  

Profile:

It is the curved formed by the face and flank is known as profile of the tooth. Gear tooth are generally have cycloidal or involute profile. 
Fillet radius

Path of contact:

The curved traced by the point of contact of two teeth form beginning to the end of engagement is known as path of contact. 

Arc of contact:

It is the curve traced by the pitch point form the beginning to the end of engagement is known as arc of contact. 

Arc of approach:

The portion of the path of contact from beginning of engagement to the pitch point is known as arc of approach.

Arc of recess:

The portion of the path of contact form pitch point to the end of the engagement is known as arc of recess.

Today we have learned about Gear terminology or the basic term used to design a gear. If you have any query regarding this article, ask by commenting below. 

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Monday, 16 May 2016

Types of Hammers

Today we will discuss about types of hammers. Hammer is widely used in mechanical industries to drive any thin metal part like nails etc. by an impact force. It is a tool which is used to create a sudden pointed force, which is further used to drive nails, remove unwanted metal parts form work piece and also in forging to create flat surfaces. Hammers are also used in our daily routine to drive nail in a wall or in wooden work piece etc.

A hammer consist two main parts. The first one is handle and the other one is head which is a heavy metal piece mounted at perpendicular to the axis of the handle. There are many different types of hammers used in mechanical industries for different uses. Now we will discuss about it.

Types of Hammers:

A hammer is a hand tool which is used to create sudden impact force. The impact of hammer depends on the size and shape of hammers and the power given to drive it. The hammer can be classified into many types according to its shapes and size but mainly there are only two hammers types.

A. Hand Powered Hammers:

As the name implies hand hammer are powered by manually human hands. According to shape and size of heads and its different uses it has following types.


Types of Hammers1. Ball peen hammer:

As shown in figure, one side of head is shaped as ball and other is flat. It is mostly used to shaping rivets and metal work pieces. It may available in different sizes.




Types of Hammers2. Claw hammer:

It is a tradition hammer which one side is a flat other side of head has a nails removing shape from wooden and other work piece. It is also known as carpenter’s hammer.



Types of Hammers3. Cross peen hammer:

This hammer have one face is like ball and other face of head is like wedge. It is mostly used in domestic work where the peen is used to straight the nails.




Types of Hammers4. Dead blow hammer:

As a name implies it deliver very large impact force.




Types of Hammers5. Engineer hammer:

It is upgrade version of drilling hammer with bigger handle. The handle size is about 14 inch and mostly used in locomotive and steam engine work.

Types of Hammers

6. Geologist hammer or rock pick hammer:

It is specially used to break or split rocks and mostly used by a geologist.





Types of Hammers7. Knife edged hammer:

One end of this hammer is knife edge and other one is flat surface. It is mostly used to cut or split wood.




Types of Hammers8. Sledge hammer:

It has a large flat metal head joint with a large handle. It is used to drive wedges.


Types of Hammers9. Rock climbing hammer:

It is a special type of hammer used to climb the rocks.




Types of Hammers10. Rounding hammer:

It is also known as blacksmith hammer. It has round face which is used to design or shapes a forged bar or sheet in blacksmith.






Types of Hammers

11. Soft faced hammer:

It has a soft face of rubber, plastic or copper. It is used where steel face may damage workpiece.



Types of Hammers12. Stonemason’s hammer:

This hammer is also known as brick hammer. One end of the head is flat and other end has a chisel like shape. It is used to split bricks or concrete wall.




Types of Hammers13. Welder chipping hammer:

It is used to remove unwanted welded area form the work piece. It is also dissipates heat.  






Types of Hammers14. Lump hammer:

It is a double face hammer and used to driving steel chisel in work piece. It is one of the types of sledge hammer which has smaller handle with light weight. It is mostly used in domestic work.





Types of Hammers15. Mechanic's hammer:

It is used to remove dents form the sheets. It has a small curve anvil at one side of head and a sharp chisel type face at other side.


16. Drilling hammer:

It is mostly used in drilling in rocks with a chisel. It has a head weight almost 2 kg attached with a handle of 10 inch which is mostly drive by one hand. Other hand is used to hold the chisel.


17. Lathe hammer:

One end of this hammer head has a hatchback blade and other end a round head at other side. It is using at lathe machine is workshop.


18. Brass hammer:


It is made by brass. It is used in flammable area to like oil or fuel fields. It prevents to spark generation during hamming.

B. Mechanically Powered Hammers:

It is driven by some of mechanical power like hydraulic power or by Gear drives.


Types of Hammers1. Hammer drill:

It is a rotary hammer which has a drill at one side which provides hammering action. It is used to drill in brittle material.



Types of Hammers2. Steam hammer:

It is steam driven hammer and used to shaping the forged material. In this hammer the hammer head is attached to a piston which driven by the steam pressure. At the piston moves down it provide impact force which used to shape the material.



Types of Hammers3. Jack hammer:

It is driven by the pneumatic pressure of electro mechanical. It is used to dig out roads.



Image Source : www.indiamart.com

Today we have discussed about types of hammers. If you have any query regarding this article, ask by commenting. 
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