AC motors (powered by alternating current) Stepping motors (motors that rotate one step at a time in response to electrical pulses) Two features that distinguish DC motors from the other two types are their high starting torque and ability to run at high speed. Horizontal scrolling. DC motor with brush. Brushless DC motor.
The Gearless Mill Drive system consists of the ring motor with its feeding cycloconverter, pre-installed in an E-house. It also includes the excitation rectifier, the automation sys-tem (for mill and motor) including HMI, monitoring and diagnostic system, MCC's …
Traction drives for on- and off-road vehicles can be designed with or without a gearbox; both variants can be useful in practice. The following text is to illustrate the respective advantages and disadvantages as well as give specific application examples of when it is advantageous to use a gearbox in an electric drive train or when a direct drive is the better …
Advantages of the wound rotor/SER drive are: If the SER converter drive fails, the drive can be switched to fixed speed bypass - starting the usual way with the LRS. The converter only needs to be sized for 15-20% of the total motor rating with associated reduction in floor space, air-conditioning etc.
drive motor and gearing and a fixed position horizontal milling machine spindle. An adjustable overhead arm containing one or more arbor supports projects forward from the top of the column. The arm and arbor supports are used to stabilize long arbors. Supports can be moved along the overhead arm to support the arbor where support is desired
The poles of the gearless or synchronous motor (also called wrap-around motor or ring motor) are directly installed on the pole flange of the mill shell, turning the mill body into the rotor. The stator is then wrapped around the mill. The gearless motor is fed by a cycloconverter which has a rated output frequency of around 5 Hz for the GMD drive.
The servo motor is an assembly of four things: a normal DC motor, a gear reduction unit, a position-sensing device, and a control circuit. The DC motor is connected with a gear mechanism that provides feedback to a position sensor which is mostly a potentiometer. From the gearbox, the output of the motor is delivered via servo spline to the servo arm.
Motor The GMD is a drive system without any gear where the transmission of the torque between the motor and the mill is done through the magnetic field in the air gap between the motor stator and the motor rotor. The concept to drive the mill this way is relatively simple using the mill body as motor rotor and mounting the poles there.
For existing installations, replacing a DC motor with a new one – as opposed to redesigning the motor circuit to use an AC motor and drive – is almost always less expensive, quicker and easier. Along the same lines, the simple design of DC motors makes service, maintenance and control well understood and easily supportable.
The SIMINE Gearless mill drives pump system significantly enhances concentrator productivity by eliminating the reducer gear between motor and pump and all corresponding maintenance. In addition, the cyclone pumps with variable speed can adjust their energy consumption to the optimized flow of pulp, resulting in energy savings of up to 30%. …
Understanding Variable Speed Drives (Part 1) Operating a motor at the outer limits of its voltage requirements reduces its efficiency and causes premature failure. Three basic types of variable frequency drives offer certain advantages as well as disadvantages depending on your motor application. The new flux vector drive is also discussed.
A Double Squirrel cage motors is powerful enough to drive a loaded conveyor belt in the normal way but if the inertia is large and the power required considerable the motor may well be distressed when starting from rest. The starting current of a motor can be as high as 600% full load current, and if stalled there is no cooling air for its fan.
A variable speed drive controls motor speed and torque by varying the motor input voltage and frequency. A very close match between motor speed and the output requirements of the machine it is ...
Motor testing assesses the integrity of a motor through the use of computer-supported equipment or tools that monitor trends within the motor. The main objective of motor testing is to reveal hidden problems and prevent unnecessary failure. Specific to electric motors, motor testing evaluates static parameters like insulation, wire damage and ...
Revised by William R. Perkins, in Reference Data for Engineers (Ninth Edition), 2002. Step Motors. Step motors are electromechanical incremental actuators that convert digital pulse inputs to analog output shaft motion. The advantage of a step motor is that the motor can be driven directly by digital inputs through the power drive, and no interface D/A conversion is …
Mill application features. Frozen charge protection – Detects frozen charge in the mill, minimizing equipment wear and liner replacements.; Coupling supervision – Detects if a failure or slippage occurs in the couplings and stops the system in case, preventing major damages.; Stand-still detection – Prevents the motors from re-starting if the mill is still rocking or moving after a …
1. Most drives have two sheaves, one on the motor and one on the driven machine. The motor base usually has slotted holes to allow for adjustment toward and away from the driven machine. Loosen the motor hold down bolts and move the motor toward the drive machine to the inner end of the adjustment to release tension on the belts. Use a pry
Reliable operation, ready for digitalization. A comprehensive portfolio of reliable frequency converters, motors, couplings and gearboxes for almost every industry and field of application satisfies the highest performance standards and quality requirements. New interfaces and modules ensure drive components are ready for digitalization.
induction motor drive's cost comes from the inverter and its controller. A principle of v/f control of the output voltage in PWM voltage-source inverters is described. The proposed approach is a modification of the sinusoidal modulation technique, and consists of
DC motors, while far less complex than servo motors are also easy to control; reverse the leads to change directions, and change the voltage to change the speed. These motors are both easily controllable, but their gap in complexity changes the resolution of control. The torque/speed range of DC motors is increased by just how many types of DC ...
AC adjustable-speed motor drive systems have been established as the preferred technology for new rolling mill installations and extensive modernization projects. The AC adjustable-speed motor drive system provides metals mills with many advantages compared to traditional DC drive technology, including: • Improved drive effi ciency
Because of this, our electric motors meet or exceed all global minimum efficiency standards. These motors are suitable for use with 60hz and 50Hz mains. In addition, NORD supplies easily cleaned smooth-body motors, single phase motors and rolling mill motors for heavy duty applications. For Ultimate Performance: Drive Electronics From NORD
"RPM AC motors are ideally suited for use in variable speed applications that have traditionally been the realm of DC motors, but RPM AC offers many advantages over DC, with the most important being reduced maintenance requirements," said Rick Kirkpatrick, Global Product Manager for Laminated AC and DC frame motors.
Direct Drive Advantages. No loss of detail. No maintenance or belts to wear. True 1:1 performance. Ability to transmit high frequency detail. No additional drive train mass or inefficiency for motor to overcome. Direct Drive Disadvantages Larger, more …
Advantages of Chain drive: A chain drive has several advantages like: Low maintenance. Greater efficiency up to 97 percent. Slipping is negligible; Chain drive can operate in wet conditions too. It can withstand abrasive conditions. The chain drive is easy to install. Initial tension is not required in chain drive.
JR slip ring motor for ball mill JR ball mill motor adopts rotor string resistance full-voltage start-up, which has the advantages of small starting current, large starting torque, high efficiency, low noise, low vibration, good ventilation performance, …
Advantages of SER drives for SAG mills Friday, December 19, 2014 For large mills requiring variable speed, the wound rotor motor and SER drive are economical for a total rating of approximately 2MW to 16MW. Above 16MW, the gearless drive (cyclo-converter) is typically used because gearboxes and pinion gears reach their present limit in size.
The main advantages of thi system are precise positioning, energy saving and increased motor life. This paper focuses on the application of variable voltage variable frequency induction motor ...
These motors are suitable for use with 50 and 60 Hz mains. In addition, NORD supplies easily cleaned smooth motors, single phase motors and rolling mill motors for heavy duty applications. We ensure the optimal control of your drive unit with frequency inverters for control cabinet installation or for decentralised use directly on the application.
important for the machine designer to select the best motor-drive system for the application, while considering the technical advantages and disadvantages of both. Stepper motors have several major advantages over servo systems. They are typically lower cost, have common NEMA mountings, offer lower torque options, and they require less
Although variable speed induction motor drives are generally expensive than d drives, they are used in a number of applications such as fans, blowers, mill run-out tables, crane conveyers, traction, etc. because of the advantages of induction motors.
DC Motors. Johnson Electric, the world leader in micro motors, offers custom engineering solutions based on a wide range of low voltage DC and high voltage DC motor platforms. The low voltage DC platform provides power density and compact packaging options. The high voltage DC range provides power density and space saving advantages versus ...
DC motors have the advantage of: higher starting torque, quick starting and stopping, reversing, variable speeds with voltage input and they are easier and cheaper to control than AC. AC motor advantages include: lower power demand on start and minimal maintenance. While the market for AC motors is larger than DC, it can be challenging to find ...
7. Slip Ring Induction Motor. It has high starting torque and large overload capacity. The speed of slip ring induction motor can be changed up to 50% of its normal speed. Slip ring induction motor is used for those industrial drives which require high starting torque and speed control such as lifts, pumps, winding machines, printing presses, line shafts, elevators …
