Steam Turbine Working Principle

The steam turbine working principle lies in the change of heat energy contained in steam which is converted into mechanical energy transmitted to the turbine rotor. This happens in several different steam turbine stages. Each turbine stage always consists of a stationary circular blade and a rotating blade.

Heat energy in steam is shown by the amount of enthalpy (h).

h = u + p.V
u = internal energy, p.V = work flow

Steam Turbine Working Principle
Converting Heat Energy from Steam into Kinetic Energy


First, heat energy must be converted to kinetic energy, this process occurs in the nozzle (see picture above). In steam turbines, nozzles are mounted on the sides of the turbine stator and also at the rotor blades, hereinafter known as reaction stage. In this nozzle, water steam increases the speed (kinetic energy increase), and this acceleration causes differential pressure between the upstream sides nozzle and downstream nozzle.

Second, the kinetic energy is transformed into a rotary energy of the turbine rotor that occurs only on the rotating blade (rotor side).

20110808-110049.jpg
Velocity Vector On Steam Turbine Reaction Stage

 

Stages on the turbine has a speed difference, as shown in the picture above. At each level, a velocity triangle is drawn, one on the rotating inlet side of the blade, and the second at the outlet side. The absolute speed (c) in the inlet and outlet have different magnitude, since the kinetic energy of water vapor is converted to mechanical energy in the rotor.

Positive Displacement Pump Working Principle

Positive displacement pump working principle, is by providing a certain force, in the form of kinetic energy, at a fixed fluid volume from the inlet side to the pump outlet. The working principle is very different from the dynamic pump, which in theory, positive displacement pump will produce a fixed flow rate at a certain RPM even though the pump output pressure is variated.

The positive displacement pump can not operate with the control valve system at the discharge line. This is because the positive displacement pump does not recognize the excess head system as in the centrifugal pump (read this following article). If the pump outlet have a throttled valve, the pump output pressure will continue to increase. This is because the positive displacement pump will continue to produce stable fluid flow, if the rotation of the work remains. The increasing output pressure due to throttling is very dangerous to the pump components, and there is a possibility of breakage so that the flow of the pumped fluid returns stable at its working point.

20121017-095828 AM.jpg
Positive Displacement Pump Symbol


In order to anticipate those phenomenon, in order to overcome excessive restriction that potentially increases pump pressure, a positive displacement pump is required to use a pressure relief valve system mounted on the output side of the pump. The relief valve serves to ensure that there will always be a flow in the positive displacement pump when it operates, despite restrictions at the pump output side which can increase pump output pressure. This relief valve will opens and flows the working fluid out of the system or returns to the pump inlet when the pump output pressure rises at a certain value. Relief valve has adjustable working pressure settings as needed. The value of this working pressure that governs when the relief valve should open.

20121017-102025 AM.jpg
Relief Valve Design

Positive Displacement Pump Characteristic Curve

As I mentioned above that positive displacement pumps have very different characteristics from dynamic pumps. The characteristic of the positive displacement pump is determined by the volume of the pump work to which it is “moved” the working fluid. The design of the working volume of the pump is fixed to a certain size, so that at a stable RPM the pump fluid flow will tend to be at a fixed value even when the pump head changes. For easier description please look at the following positive displacement pump characteristic curves.

20121017-051848 PM.jpg
Positive Displacement Pump Characteristic Curve

Comparison of Centrifugal Pumps With Positive Displacement Pumps

Next let us discuss some basic features between the centrifugal pump and the positive displacement pump. First is the characteristic curve of the two pumps.

20121018-034517 AM.jpg

From the curve above, there are striking differences between the two pumps. Variations of fluid flow discharge at the centrifugal pump will always be accompanied by head variations as well. Whereas in positive displacement pumps, variable pump heads tend to be at relatively stable flow rate.

20121018-035108 AM.jpg



The second is the influence of fluid viscosity on fluid flow discharge. In the fixed RPM, the centrifugal pump tends to decrease the flow rate as the viscosity of the working fluid increases. Unlike positive displacement pumps the flow discharge tends to rise as the fluid viscosity rises. This is because the higher viscosity of the working fluid, the clearence of the pump will be more fulfilled by the fluid and result in increased volumetric efficiency of the pump. On this basis the use of positive displacement pumps is particularly suitable for high viscosity working fluids, such as their use in hydraulic systems.

positive displacement pump working principle

The next parameter is the mechanical efficiency value of the pump when operated at a high head. It appears that positive displacement pumps are better at mechanical efficiency at high pump head, in contrast to centrifugal pumps that have optimum mechanical efficiency points but will decrease as pump head increases.

20121018-031654 PM.jpg

The viscosity of the working fluid also affects the mechanical efficiency of both pumps. Thicker viscosity of a working fluid, will lowering the mechanical efficiency of the centrifugal pump, due to the decrease in frictional losses. In contrast to positive displacement pump which would increase its mechanical efficiency if the viscosity of the fluid gets thicker.

Centrifugal Pump Working Principle

Centrifugal pump is one kind of the dynamic pump type. This pump is pushing the fluid in a perpendicular direction to the impeller shaft/axis. Different from the axial pump which the fluid output direction is parallel to the axis of the impeller.

Centrifugal pump is composed of an impeller with inlet channel right in the middle. Centrifugal pump impeller have different design with axial pump impeller. Centrifugal pump impeller will create a centrifugal force to push the fluid from the center of the pump (inlet) to the outside of impeller. So, when the impeller rotates by mechanical energy generated by the driving source, fluid flows from the inlet to the outer side of the impeller ahead to the pump casing.



One elementary part of centrifugal pump other than impeller is the pump casing. Centrifugal pump casing have unique design like a snail shell. This snail-shell-shape have function to decreases the fluid flow velocity while impeller rotation speed remains high. The fluid velocity is converted into pressure by this casing so that the fluid can reach its outlet point.

Centrifugal pump has some advantages include smooth operation in pumps, uniform pressure at pump discharge, low cost, and can work at high speeds so that further applications can be connected directly with steam turbines, electric motors, or other driving source. The use of centrifugal pumps in the world reaches 80% because of its suitable use to cope with large amounts of fluid than positive-displacement pumps.

How to Control the Flow of Centrifugal Pump System

Centrifugal pumps become one of the most widely used in the industrial world. Here are some reasons:

  • Strong construction
  • Simple design
  • Low fabrication costs
  • Easy operation
  • Easy-to-manage system controls

The working principle of a centrifugal pump is by transfer of motion energy from the rotation of the driving shaft to the pump impeller thus creating the centrifugal energy transferred to the fluid flowing within it. The flow of centrifugal pump output can be varied both head and discharge values, according to system requirements. Because sometimes the system does not always want the fluid flow always constant at a certain value. This is not possible with positive displacement pumps.

One example is the Boiler Feed Water Pump used in steam power plants. This pump supplies the amount of discharge water flow adjusted to the existing electrical load.

Here are ways to adjust the discharge flow and head output of a centrifugal pump:

Controlling Flow Discharge With Discharge Control Valve

The simplest way to vary the discharge of the pump fluid flow is to use a control valve that can be adjusted for the amount of openings and mounted on the output side of the pump.

20120924-112930 PM.jpg

The purpose of using the control valve at the pump outlet is to increase the restriction of the existing fluid flow, so that there is a shift in the system characteristic curve upwards. If the pump operates at a constant rotation, the pump operational point shifts to the pump characteristics curve line toward the lower flow rate.

20120924-115631 PM.jpg



The sliding of the system characteristic curve results in the decrease of the system discharge requirement as desired. But on the other hand the need for system head (downstream control valve) actually does not change lower. This results in an excess head or leftover head compensated by a throttling valve system that creates pressure drop.

Advantages:

  • Cheap price
  • Good use on system with load often 100%
  • Good to use on short time operational control
  • It is suitable for pumps with flat characteristic curves

Disadvantages:

  • The pump output pressure is too high
  • The pump efficiency becomes low if it is throttling position
  • Not energy efficient if being throttling position
  • The control system is not good if the excess head is high
  • There is a mechanical load on the valve when throttling position
  • There is a risk of making noise when it is high throttling position

Controlling Flow With Minimum Flow Control Valve

The minimum flow is a line attached parallel to the pump and connects directly or indirectly between the output side of the pump and the inlet side of the pump. In this system the fluid flow of the pump output is divided into two, one direction fixed to the system while the other returns to the inlet side of the pump. In this way we can adjust the flow of fluid into the system by regulating the amount of fluid that passes through the minimum flow, of course with the help of the control valve.

20120926-075228 PM.jpg

Through the pump and system characteristics curve we can note that in this way, we can adjust the discharge pump output to the system without having change the pump head value at its operational point. So the excess head value is not as big as if the system only uses the throttling system on the pump output side.

20120926-093341 PM.jpg



Advantages:

  • There is no increase in head even if the pump works on partial load.
  • The value of the pump’s output pressure is fixed even if the flow discharge varies.
  • Suitable for use in systems that require low head but high flow.
  • Easy to control if full pump load is required.

Disadvantages:

  • The cost of system construction is more expensive.
  • There is no decrease in power requirements at partial load.
  • There is still an excess head at partial load.
  • In terms of energy needs, this system is not economical.

Controlling Flow With Variation of Speed Rotation

One way to get variation of the flow discharge of centrifugal pump is by varying the speed of the pump rotation. If the pump rotation is changed, the pump characteristic curve will shifted. When the rotation is faster, the curve will shift to the right. Whereas if the rotation is slower, then the curve will shift to the left. The curve shift is parallel to the initial position, so the head and flow rate at each curve point may vary according to the variation of the speed rotation used.

20121004-075603 AM.jpg

There are several ways we can use to control the pump in order to have a speed rotation variation:

  1. Using an electric motor that can vary its rotational speed. AC electric motors can be varied in rotational speed by using more magnetic poles on the rotor side. This will increase the cost of production. While on the DC electric motor, simply by changing the volume of the supply voltage so that it can vary the magnitude of rotation.
  2. Using a gearbox system.
  3. Using a belt transmission system with a variable pitch diameter.
  4. Using a hydraulic transmission system.
  5. Using a steam turbine as a rotating driver can be adjusted by adjusting the amount of steam that enters the turbine to move the blades.


Advantages:

  • Can avoid excess head.
  • Smooth pump ignition due to speed inverter.
  • The pump components will last longer.
  • Reduce the effect of hydraulic feed-back.
  • Energy saving.
  • Low electrical load (if using an electric motor) due to the large current low when the pump is turned on.
  • Reduce maintenance costs.

Disadvantages:

  • The cost of the control system is high.

Controlling Flow By Installing Multiple Pumps In Parallel

If several centrifugal pumps are installed in parallel, then the total discharge flow is the sum of the flow rate of all pumps at work. In this way, we can adjust the fluid flow by running a number of pumps simultaneously in accordance with system requirements. The characteristic curve of the pump and the system becomes the reference work for each pump.

20121004-083832 AM.jpg

Parallel pump characteristic curve is obtained by summing the fluid flow from several pumps at the same head value. In practice, higher flow rate will also increase the resistance of the system. So, to compensate these obstacles, the operating point of the pump becomes a higher practical pressure value than its theoretical pressure value.

20121004-084959 AM.jpg

Advantages:

  • It is suitable for system curve characteristic which has high static head component.
  • Good adaptation on partial load.
  • High system efficiency.
  • Low cost control on the operating system.
  • Reliable operational system.

Disadvantages:

  • Construction costs are high.
  • The operational switching frequency of the pump is high if the system design is not appropriate.
  • Problem with fluctuation of pump inlet pressure.

Axial Pump Working Principle

An axial pump is one kind of the dynamic pump type. This pump serves to push the working fluid in a direction parallel to the axis/shaft impeller. Different from the centrifugal pump which the fluid output direction is perpendicular to the axis of the impeller.

The mechanical energy generated by the driving source is transmitted through the impeller shaft to drive the pump impeller. The impeller rotation gives the axial force to drives the fluid and produce kinetic energy. In some axial pump designs, there is mounted blades at the stator side, forming a diffuser at the pump outlet. Its function is to remove the rotating effect of the working fluid and to convert the kinetic energy contained, into working pressure.

20121005-024623 PM.jpg

Axial pumps are used on systems that require high fluid flow discharge, with low head requirement. This type of pump is widely used in irrigation systems, flood prevention pumps, and in steam power plants are used to supply seawater as a cooling medium in condensers.

20121005-022728 PM.jpg
Centrifugal vs Axial Pumps Characteristic Curves



Here are some comparison between axial pump with centrifugal pump:

  • As seen from the efficiency curves, centrifugal and axial pumps have almost the same maximum efficiency levels.
  • If the fluid flow decrease, the input power for the centrifugal pump becomes decrease too. But at the axial pump the input power goes up to maximum when the fluid flow stops.
  • The axial pump may cause overload at the motor drive if the flow rate is drastically reduced from its design capacity.
  • Head generated by centrifugal pumps are much higher than axial pumps.
  • On an efficiency curve beyond its maximum efficiency, the axial pump has a lower efficiency level than a centrifugal pump.

How To Read The Pump And System Characteristic Curve

Theoretical explanation of the pump characteristics curve, you may read the previous article. The pump characteristic curve is influenced by the size and design of the pump, the size of the impeller diameter, as well as the magnitude of the operating rotation. The characteristics of a pump are shown through a head vs flow pump. On this curve also included some information about the associated pump such as BHP, NPSHR, hydraulic efficiency point, and pump power characteristics.

Now lets talk about the system characteristic curve. The system characteristic curve is used to determine which centrifugal pumps will be installed on the system. A fluid flow system can generally be described in a characteristic curve called the system characteristic curve.

Kurva Karakteristik Sistem Aliran Fluida
Characteristic Curve of Fluid Flow System


Like the pump characteristics curve, the system characteristic curve is also the head on vertical axis and the flow at horizontal axis. The head of the system curve is a function of the static head of the system, and its losses. This can be expressed through the following equation:

h = dh + hl

Where:

h = head system
dh = head elevation system / height difference between system inlet and outlet
hl = the head loss of the system

If the loss of the head is greater, such as if the discharge valve system is throttled, will result an increased of head loss. Thus shifted the system characteristic curve upwards. At the start point of this curve, the system head value is not equal to zero, so even if there is no flow in the system the head is equal to the value on the curve.

Cara Memilih Pompa Sentrifugal
How to Select a Centrifugal Pump

 

To determine the exact centrifugal pump used on a system, the pump characteristics curve and system characteristic curves are combined. The meeting point between the two curves is an operational point if the associated pump used on the system. The most optimal operational point is if the meeting point between the two curves is in the BEP (Best Efficiency Point) area.

The pump operating point shall be kept to the highest pump efficiency area as far as possible. Especially the operation of the pump is used on systems that require head variation and large fluid flow, so there will be a shift in the system curve.

What is Pump Characteristic Curve?

Each pump made by the manufacturer has different characteristics in accordance with the function and design of the manufacturer. This pump characteristic curve is influenced by the size and design of the pump, the diameter of the impeller, as well as the speed of its operating rotation. Pump characteristics are shown through a head capacity vs discharge pump curve.

Kurva Performa Pompa
Head-Capacity Curve of Centrifugal Pump

The above characteristic curve of the pump is also known in engineering and industrial world as the Pump Performance Curve.

If a particular pump is kept constant in its rotation speed, then we can shift the performance curve by varying the size of the impeller diameter as below.

Variasi Diameter Impeller

Similarly, if we keep the pump impeller diameter in constant condition, then we vary the speed of the pump rotation, then we can also shift the pump performance curve to the right or left.

Variasi Kecepatan Putaran Pompa



The variation of pump conditions above does seem less prevalent. But in the industrial world it is a common thing. In Steam Power Plant for example, the main pump that supplies water to the boiler must be able to vary the discharge water flow in accordance with the needs of water vapor that will be produced by the boiler. Changes in electrical load then the need for water vapor is also different. The variation of pump rotation speed becomes a reasonable solution for use in this industry.

Additional Components of Pump Characteristics Curves

There are other things we need to know about some of the parameters that are usually included in the pump characteristics curve. The first is the Brake HorsePower (BHP) information required to operate the pump. BHP, also known as pure engine power, is a unit of power designation of a machine before it’s reduced by losses due to system design or other losses.

Informasi BHP Sebuah Pompa
BHP Information On Pump Characteristics Curve

Keep in mind that the BHP information on the pump characteristics curve is for a water fluid that has a specific gravity value = 1. If the pump will be used for another fluid, then the BHP value must be calculated first. For example the fluid to be used is gasoline with a specificity value of 0.72, then the required value of BHP is:

5 bhp x 0,72 = 3,6 bhp

Other information provided with the pump characteristics curve is usually the point of its hydraulic efficiency. Best Efficiency Point (BEP) / hydraulic efficiency is the pump efficiency that has been reduced by losses due to hydraulic effect.

Efisiensi Hidrolik
The Best Hydraulic Efficiency Shown On The Curve

The third parameter is Net Positive Suction Head Required (NPSHR). NPSHR is a pump parameter which the value was obtained from the lab test. The NPSHR is a quantity to indicate the losses of the internal pump. The magnitude is determined by the pump design, its size, and its rotational operation.

Contoh NPSHR
NPSHR Curve of a Pump


Large NPSHR is affected by the rotation speed of the pump when used on the system. While the pump rotation depends on the design of the system itself. Another case with NPSH whose value is directly influenced by system design. The actual NPSH (Net Positive Suction Head) value must always be higher than this NPSHR value.

The last information on the pump characteristics curve we need to consider is the ability of the pump to lift the water from the inlet side to the outlet. This term we know as the priming lift.

Priming Lift Information

On the curve above, the ability of the pump to lift water from a certain depth at each impeller diameter. This information is very important especially when we choose pump to be used on a deep system.

Axial Pump Components

The axial pump components are not much different from the centrifugal pump. The most noticeable difference is the diffuser design between the centrifugal pump and the axial pump. In accordance with the impeller design, centrifugal pumps are emphasized to generate high head fluid pressure, while axial pumps emphasize high flow fluids. For that, the diffuser design on the centrifugal pump (in this case is the volute casing) is more “extreme” when compared to the diffuser in the axial pump.

20121007-045106 PM.jpg
Axial Pump Parts


Based on the image above, here are the main parts of the axial pump:

  1. Pump Inlet. This part becomes the inlet side of the fluid to get into the pump. In a vertical axial pump, the inlet side is funnel-shaped (so-called Suction Bell) in order to reduce the hydraulic head loss.
  2. Impeller. Impeller becomes the main part of this pump. The design is similar to a propeller on a ship. This impeller serves to induce an axial force which is transferred to the working fluid.
  3. Diffuser. The axial pump casing is also like a diffuser-shaped on centrifugal pump. Its function is to lowering the pump speed and raise the working pressure. However, the design is not as extreme as the volute casing of the centrifugal pump, because the increased outlet pressure of the axial pump outlet may cause vibration and reduce the working life of the axial pump. Once again, the main function of axial pump is to achieve high fluid flow, not high fluid pressure.


  4. Shaft. Serves to continue the rotation of the electric motor to the impeller.
  5. Guide Bearing. Serves to hold the position of the shaft to stay on the axis line work. These bearings require a lubrication system that must be maintained to avoid temperature rise.
  6. Stuffing Box. Is a sealing system that serves as a barrier between the shaft with the casing to avoid leakage.

Here is the detailed picture of axial pump parts:

20121007-111400 PM.jpg
Parts of Pump Inlet Sides

 

20121007-111414 PM.jpg
Parts of Drive-End Side of Pump

 

20121007-111510 PM.jpg
Example of Installing a Vertical Axial Pump

 

(Source: fpipumpscanada.com)

Centrifugal Pump Components

Generally, centrifugal pump components are include:

  1. Casing
  2. Impeller
  3. Shaft
  4. Bearing
  5. Clutch
  6. Packing & Seal
  7. Lubrication System

20120902-044515-PM



Pump Casing

The first major component of a centrifugal pump is the pump case. Centrifugal pump casing is designed in the form of a diffuser that surrounds the pump impeller. This diffuser is more commonly known as a volute casing. In accordance with the function diffuser, volute casing serves to reduce the flow rate of fluid into the pump. At the pump outlet, the volute casing is designed to form a funnel that convert kinetic energy into pressure by lowering the speed and raising the pressure, also helping the balance the hydraulic pressure on the pump shaft.

Volute Casing
Volute Casing

 

Impeller

Impeller is the rotating part of the centrifugal pump, which serves to transfer energy from the motor rotation to the pumped fluid by accelerating it from the center of the impeller to the outer side of the impeller.

20120906-122819 AM.jpg
Some examples of impeller types

 



The impeller design depends on pressure requirements, flow velocity, and conformance with the system. Impeller becomes the main component affecting pump performance. Modification of impeller design will directly affect the shape of the pump characteristics curve. There are various designs of centrifugal pump impeller, including closed and open type, single flow type, mix flow type, radial type, non-clogging type, single stage type, and multi stage type.

Shaft

The pump shaft is the part that transmits the rotation of the source of motion, such as the electric motor, to the pump. What we need to note is that, on a centrifugal pump working at its best efficiency point, the bending force of the shaft will be perfectly distributed throughout the pump impeller part.

Bearing

Pump bearing is to hold (constrain) the position of the rotor relative to the stator in accordance with the type of bearing used. Journal bearing serves to withstand gravity and forces in the direction of that heavy force, and thrust bearings serves to resist the axial force that arises on the pump shaft relative to the pump stator.

20120906-014036 AM.jpg
Journal and Thrust Bearing

 



Coupling

Basically the coupling serves to connect two shafts, one of which is the driving shaft and the other is the driven shaft. The coupling used in the pump depends on the system design and the pump itself. The various coupling used in the pump can be rigid coupling, flexible coupling, grid coupling, gear coupling, elastrometic coupling, and disc coupling.

Packing System

The packing system at the pump is to control the fluid leak that may occur on the border between the pumping part (spindle) and the stator. Sealing systems that are widely used in centrifugal pumps are mechanical seals and gland packing.

20120906-024527 AM.jpg
Mechanical Seal System

 

20120906-024655 AM.jpg
Gland Packing System

 

Lubrication System

The lubrication system at the pump serves to reduce the coefficient of friction between the two surfaces that meet, thus reducing the risk of wear. Lubrication at the pump is mainly used in bearings. The system can be either lub oil or greas type depending on the pump design itself.

Types of Car Transmission (Part 4)

( Continued from previous articles. )

Types of Automatic Transmission Based on Technological Advancements

Innovations from various car manufacturers of the world have produced many highly sophisticated automatic transmission technology. The development of mechanical and electrical automatic control systems makes motor vehicle designers competing to produce a fast and precise transmission system during gearshift, reduced torque losses on converter torque usage, and more efficient transmission systems to power the engine to each driving wheel. Thus came the following technologies of automatic transmission systems:

  1. Manumatic Transmission
    Manumatic comes from manual and automatic. Manumatic transmission means a transmission system which is automated, but the driver can choose the option to manually move the transmission. But here the rider is not fully manually switching his transmission ratio, because there is no clutch pedal. The rider simply chooses the sign (+) to raise the ratio or the sign (-) to decrease the ratio and the displacement of the tooth ratio occurs sequentially. All engine transmissions are still automatically performed by the automatic transmission system.

    20121106-090052 AM.jpg

    Manumatic Mazda CX-7 Transmission Handle

    Almost every car manufacturer has its own brand for its manumatic transmission system, such as Sportronic (Alfa Romeo), TouchTronic (Aston Martin), Tiptronic (Audi), Steptronic (BMW), SelectShift (Ford), iShift (Honda), Bosch Mechatronic (Jaguar), Sportmatic (KIA), TouchShift (Mercedes-Benz), Protronic (Proton), Geartronic (Volvo), and so forth.

  2. Semi-Automatic Transmission
    Semi-automatic transmission can not make full automatic transmission ratio transfers. The switching between ratios must be initiated by the rider. This transmission does not use the clutch pedal that must be pressed by the rider each want to move the transmission ratio, the rider simply shift the paddle or press the button normally located on the steering wheel.

    This transmission uses electrical sensors, pneumatic systems, processors, and actuators to execute driver commands while moving the transmission ratio. This system eliminates the position of the clutch pedal in the car’s cockpit with an automated electronic system to actuate the clutch on the transmission system. This automated electronic system controls the clutch by reading the signal shaft rotation, torque signal, and the right time to get a fast and smooth gearshift.

    20121106-100922 AM.jpg

    Paddle Shift on Ferrari F430

    Transmission systems do not use planetary gear transmissions, but have used gear wheels with parallel shafts as in manual transmissions. This design is better in forwarding the engine power to the wheels. In addition, with automatic gear coupling actuation system, got the process of gearshift very quickly. Ferrari F430 for example, switching between rations only takes 150 ms (milliseconds).

  3. Electrohydraulic Transmission .
    The next technology is automatic transmission system called electrohidrolic system. The main feature of this system is the use of automatic computation control systems to regulate the hydraulic system in charge of clutching couplings on automatic transmissions. This system uses a variety of sensors to get a fast and efficient ratio transfer. Torque sensor, rotation speed sensor and shaft drive axle, as well as other sensors to replace the mechanical system used in conventional automatic transmission.
    ( Click here, for the Electrohydraulic System ebook )
  4. Dual-Clutch Transmission
    The dual-clutch system is a transmission system that uses two sets of gears on a gear system. This system uses two clutches, one larger set as the odd gear, while the other smaller clutch adjusts the even gear. This system produces a much faster speed transfer ratio. In addition, this dual-clutch system eliminates the torque converter position with the clutch, so that automatic transmission is also used in the electrohydraulic automatic control system.

    20121106-013952 PM.jpg

    Dual-Clutch Transmission System Scheme

    Animated Dual-Clutch Transmission System on Honda VFR1200F