Air motors are the motors that use the compressed power of the air in order to generate the necessary torque to produce the rotational motion. There are many types of applications that use the air motors. The air motors are used to provide the continuous rotary power, which is used for many purposes. Let us compare the air motors with the electric motors.
AIR MOTORS VERSUS ELECTRIC MOTORS
There are advantages as well as disadvantages of air motors in comparison to the electric motors. Let us discuss the advantages first.
The first advantage of air motors is that these motors do not need any electric power to run and hence, they can easily be used in volatile atmospheres also. The power density of the air motor is higher and thus, air motor the same size as that of electric motor can deliver more power. Most of the air motors can operate without any type of auxiliary speed reducers unlike electric motors. Overloads cause no harm to the air motors whereas in the case of electric motor, it can easily trip the circuits, which have to be restored. To control the air motors, no electronic speed controls are required as in the case of electric motor as these can easily be controlled by simple flow control by means of valves. By regulating the pressure, the torque produced by the air motors can easily be varied. Also, air motors do not need any magnetic starters like the electric motors. One of the most important advantages of air motors is that these motors generate very less heat as compared to the electric motors.
There are some disadvantages also of the air motors as compared to the electric motors. If there is no reliable source of compresses air, the cost of the air motor along with other support equipments can be much more than the electric motors. The cost of operating the air motors is very much as compared to the electric motors. Other disadvantage is that the electric motors can easily control the speed in more accurate way unlike air motors. If the flow of air or the pressure is disturbed, the torque being produced by the air motors suffers in a great way. So, there are some drawbacks of air motors also. Let us now discuss the various designs of the air motors available in the market.
DESIGNS OF AIR MOTORS
There are many types of designs of air motors that are available in the market. The common designs are axial piston, rotary vane, radial piston, V type, diaphragm, turbine and the gerotor. The types of air motors that are most commonly used for the industrial applications are the rotary vane, gerotor motors, axial and the radial pistons. The reason for these designs to become more common is that these types of air motors run with more efficiency as compared to the other types of air motors and the life of these motors is also more. These motors of course use the lubricated air to operate. V type and the diaphragm motors are the air motors that are used for the specific types of tasks. There are also many circumstances when the use of the lubricated air is undesirable and in such circumstances, some other designs that specifically use the non-lubricating air. Turbine air motors are used in such cases where the high speed is required but the starting torque required is very low.
Piston air motors are used in those applications where the high power as well as high starting torque is required. It is also used in those applications where the accurate speed control is required at low speeds. In these types of motors, there are from two to six cylinders that are attached either radially or axially within the housing. The output in the form of high torque is produced by way of pressure that acts on the pistons, which reciprocate in the cylinders. It is always advised that for getting a smooth torque, motors with four or more cylinders must be used as the two or three cylinder motors can undergo the power stroke at any moment within the revolution.
Radial piston air motors are well suited for the continuous operations. Such motors have the highest starting torque and are used for the applications that require the high starting loads. The torque is provided in the forward as well as in the backward directions and the overlapping power impulses gives the necessary torque. As far as the size of these motors is concerned, the size ranges from about 35 hp to the speeds of 4500 rpm. Thus, high torque can easily be provided by this type of motor.
Axial piston motors are more compact as compare to the above type of air motors and thus, these types of motors are very much ideal for the mountings that are done in the close quarters. These motors are grease lubricated and their design is also complex one. They are of course costlier than the vane motors. These motors can easily tolerate the high temperatures and the maximum available size in such motors is about 3.5 hp.
Vane air motors contains the axial vanes that are fitted into the radial slots the run to the full length of the motor. These types of air motors are basically used in the applications that require low to medium outputs. These can easily drive portable power tools.
Given above are the various types of air motors.
AIR MOTORS ARE QUITE EFFICIENT
There are some advantages as well as disadvantages of air motors over the electric motors. Air motors are available in different types of designs and are used for much purpose in different types of applications. The advantages of air motors are far more than the disadvantages. Thus, it can be said that the air motors are quite efficient and support many types of applications. There are many designs available and each of these designs is appropriate for a particular type of application. The use of these motors must be done with proper care so that the specific type of air motor is used in the desired application in order to get the desired results.
AIR MOTORS VERSUS ELECTRIC MOTORS
There are advantages as well as disadvantages of air motors in comparison to the electric motors. Let us discuss the advantages first.
The first advantage of air motors is that these motors do not need any electric power to run and hence, they can easily be used in volatile atmospheres also. The power density of the air motor is higher and thus, air motor the same size as that of electric motor can deliver more power. Most of the air motors can operate without any type of auxiliary speed reducers unlike electric motors. Overloads cause no harm to the air motors whereas in the case of electric motor, it can easily trip the circuits, which have to be restored. To control the air motors, no electronic speed controls are required as in the case of electric motor as these can easily be controlled by simple flow control by means of valves. By regulating the pressure, the torque produced by the air motors can easily be varied. Also, air motors do not need any magnetic starters like the electric motors. One of the most important advantages of air motors is that these motors generate very less heat as compared to the electric motors.
There are some disadvantages also of the air motors as compared to the electric motors. If there is no reliable source of compresses air, the cost of the air motor along with other support equipments can be much more than the electric motors. The cost of operating the air motors is very much as compared to the electric motors. Other disadvantage is that the electric motors can easily control the speed in more accurate way unlike air motors. If the flow of air or the pressure is disturbed, the torque being produced by the air motors suffers in a great way. So, there are some drawbacks of air motors also. Let us now discuss the various designs of the air motors available in the market.
DESIGNS OF AIR MOTORS
There are many types of designs of air motors that are available in the market. The common designs are axial piston, rotary vane, radial piston, V type, diaphragm, turbine and the gerotor. The types of air motors that are most commonly used for the industrial applications are the rotary vane, gerotor motors, axial and the radial pistons. The reason for these designs to become more common is that these types of air motors run with more efficiency as compared to the other types of air motors and the life of these motors is also more. These motors of course use the lubricated air to operate. V type and the diaphragm motors are the air motors that are used for the specific types of tasks. There are also many circumstances when the use of the lubricated air is undesirable and in such circumstances, some other designs that specifically use the non-lubricating air. Turbine air motors are used in such cases where the high speed is required but the starting torque required is very low.
Piston air motors are used in those applications where the high power as well as high starting torque is required. It is also used in those applications where the accurate speed control is required at low speeds. In these types of motors, there are from two to six cylinders that are attached either radially or axially within the housing. The output in the form of high torque is produced by way of pressure that acts on the pistons, which reciprocate in the cylinders. It is always advised that for getting a smooth torque, motors with four or more cylinders must be used as the two or three cylinder motors can undergo the power stroke at any moment within the revolution.
Radial piston air motors are well suited for the continuous operations. Such motors have the highest starting torque and are used for the applications that require the high starting loads. The torque is provided in the forward as well as in the backward directions and the overlapping power impulses gives the necessary torque. As far as the size of these motors is concerned, the size ranges from about 35 hp to the speeds of 4500 rpm. Thus, high torque can easily be provided by this type of motor.
Axial piston motors are more compact as compare to the above type of air motors and thus, these types of motors are very much ideal for the mountings that are done in the close quarters. These motors are grease lubricated and their design is also complex one. They are of course costlier than the vane motors. These motors can easily tolerate the high temperatures and the maximum available size in such motors is about 3.5 hp.
Vane air motors contains the axial vanes that are fitted into the radial slots the run to the full length of the motor. These types of air motors are basically used in the applications that require low to medium outputs. These can easily drive portable power tools.
Given above are the various types of air motors.
AIR MOTORS ARE QUITE EFFICIENT
There are some advantages as well as disadvantages of air motors over the electric motors. Air motors are available in different types of designs and are used for much purpose in different types of applications. The advantages of air motors are far more than the disadvantages. Thus, it can be said that the air motors are quite efficient and support many types of applications. There are many designs available and each of these designs is appropriate for a particular type of application. The use of these motors must be done with proper care so that the specific type of air motor is used in the desired application in order to get the desired results.
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