Balancing Machine Mainly Used For Measuring Unbalance
Balancing machines are machines that measure the size and position of the unbalance of rotating objects (rotors). When any rotor of the balancing machine is rotated about its axis, a centrifugal force is generated due to an uneven mass distribution with respect to the axis. This unbalanced centrifugal force on the rotor bearings will cause vibration, noise and accelerate the wear and tear bearings, so seriously affect the performance and life of the product. Rotor parts, such as motor rotors, machine tool spindles, crankshafts of internal combustion engines, steam turbine rotors, gyroscopic rotors and watch balance wheels, need to be balanced for smooth and normal operation during the manufacturing process.
Based on the data measured by the balancing machine, the unbalance of the rotor can be corrected to improve the mass distribution of the rotor with respect to the axis so as to reduce the vibration generated during the rotation of the rotor or the vibration force acting on the bearing to the allowable range. Therefore, the balancer is essential to reduce vibration, improve performance and improve the quality of the equipment.
Normally, rotor balance includes two steps of measurement and correction of unbalance. Balancing machines are mainly used for measuring unbalance. Corrections of unbalance are often made by means of other auxiliary equipment such as drilling machines, milling machines and spot welders, or by hand The method is completed. Some balancing machines have made the calibration device a part of the balancing machine.
Gravity balancing machines and centrifugal balancing machines are two types of typical balancing machines. Gravity balance machine is generally called static balance machine. It relies on the gravity of the rotor itself to measure the static imbalance.
If there is an imbalance in the rotor placed on the two horizontal rails, it will cause the rotor to roll on the rails with a moment of gravity on the axis until the imbalance is at its lowest position.
The balanced rotor is placed on a bearing supported by a hydrostatic bearing, and a mirror is fitted under the bearing. When there is no imbalance in the rotor, the light beam emitted by the light source is reflected by the reflector and projected on the origin of the polar coordinate of the unbalance indicator. If there is an imbalance in the rotor, the rotor mount tilts under the unbalanced moment of gravity and the mirror below the mount tilts and deflects the reflected beam so that the light cast on the polar indicator Point will leave the origin. According to the coordinates of the spot deflection, you can get the size and location of the imbalance.
Gravity balancing machine is only suitable for some disc less demanding parts. For the balancing of the rotor, the general use of centrifugal single-sided or double-sided balancing machine.
Centrifugal balancing machines measure the imbalance based on the supporting vibrations caused by rotor unbalance or the vibrating force acting on the support while the rotor is rotating. According to the different number of calibration planes, it can be divided into single-sided balancing machine and double-sided balancing machine. Single-sided balancing machine can only measure a plane imbalance (static imbalance), although it is measured when the rotor rotates, but still belong to the static balancer. Double-sided balance function to measure dynamic imbalance, but also to measure the static imbalance and even unbalanced, commonly known as dynamic balancing machine.
Centrifugal balancing machine according to the different support characteristics, but also can be divided into soft support balancer and hard support balancer. The balancing speed is higher than the natural frequency of a bearing system called the soft support balancing machine. This balancing machine has a small support stiffness and the signal detected by the sensor is proportional to the vibrational displacement of the support. The equilibrium speed is lower than the natural frequency of a bearing system called hard bearing balancing machine, the balancing machine support stiffness, the sensor detects the signal and the bearing vibration is proportional to the force.
Balancing machine with the main performance of the minimum remaining amount of unbalance, and the amount of unbalance reduction rate of two comprehensive indicators said. The former is the balance of the rotor to achieve the balance of the minimum amount of unbalance, it is to measure the balance of the highest balance of capacity indicators; the latter is a correction after the reduction of the imbalance and the initial imbalance ratio, which is a measure of the balance of efficiency Indicators, generally expressed as a percentage.
In modern machinery, flexible rotor balancing machines have been developed due to the widespread use of flexible rotors. Such balancing machines must be stepless speed control within the rotor speed range; in addition to measuring the vibration or vibration bearing vibration, but also to measure the rotor deflection. Flexible rotor balancing machines are sometimes installed in a vacuum enclosure to suit the balance of a rotor such as a turbine with a large assistive device such as a vacuum system, a lubrication system, a lubricant degassing system and a data processing computer system.
According to the needs of mass production, auto balancing machines that can automatically perform balancing measurement and balance correction for specific rotors, as well as automatic balancing lines, Hyundai has a large number of equipment in the automotive manufacturing, motor manufacturing and other industrial sectors.