Time: 2016-05-23
Modern processing equipment manufacturers in order to achieve the optimization of ball mill technology, the ball mill starter also been upgraded. It is generally soft start device which allows the mill production process stability, it is possible to effectively avoid the traditional ball mill to start slowly. This ball mill starter requires correct operation when in use, in order to ensure normal operation of equipment.
Soft start device using a ball mill is generally cage asynchronous three-phase motor rotation means by fluid coupling or V-belt and gear driven cylinder with a suitable rotational speed, the more complicated technology and methods, so during the operation must pay attention to.
Mill start-up requirements
1, when the motor starts rotor mill will produce large relative velocity, will have a great group Rao induced emf and induced current. Motor rotor speed to accelerate, the stator current is decreased rapidly, the motor starting current has no effect on the motor itself, but due to the cumulative effects of heat can cause motor overheating and damage. Therefore, the production should be avoided as often as possible to start the motor.
2, if the motor starting torque is too small, then the motor will not start at full load, it is safe to start the motor by idling. However, the actual production can not be achieved, it requires motor starting current should be smaller, and has a suitable starting torque.
Mill motor starting mode
1, direct start. Direct start is to use the knife switch or contactor AC motor is connected directly to the power supply with the rated voltage. This method is the most direct, most convenient to operate. Usually only 7.5kw motor power does not exceed the applicable small ball.
2, star delta buck starts. The specific process is when the motor is started, the motor stator windings of the first star-connected, the motor speed to be increased to close to rated speed, then the motor stator winding is converted into startup mode delta connection. This method can reduce production costs and extend machine life and high reliability. For small and medium mill 4kw-100kw start.
3, from the lotus buck starts. Is the use of three-phase autotransformers motor terminal voltage during startup to reduce start-up mode. For medium to large ball mill 100kw-320kw start.
Through the above analysis, we are given the right to be able to start the device in a ball mill use, to eliminate safety hazards, to avoid unnecessary problems.