Balancing increases the efficiency of grinding processes
Any unbalance in a grinding wheel lowers the quality of a workpiece and costs money. In the worst-case scenario, downtimes occur. Automatic balancing systems permanently monitor the spindle vibrations and automatically correct grinding wheel unbalance within prescribed vibration tolerances.
Unwanted vibration due to wheel unbalance relative to the workpiece surface lead to surface defects such as chatter marks and to the impairment of shape and dimensional accuracy. Unbalanced grinding wheels can also result in reduced spindle bearing life and early spindle failure. Technologically necessary grinding speeds cannot be maintained due to excessive vibration, leading to slower throughput and productivity.
Given the increasing accuracy requirements for manufactured workpieces and simultaneous shortening of cycle times of grinding processes, it is becoming more and more important for the grinding industry to keep grinding wheel vibration to a minimum
Traditional balancing methods such as stroboscopic balancing, balancing scales, and balancing stands are time-consuming and require specialist knowledge. When balancing outside the grinding machine, residual unbalance in the spindle bearing and clamping errors are also not dealt with. Due to the reduction of the grinding wheel diameter during processing, the unbalance changes continuously, which is why it needs to be measured permanently and rebalanced if necessary.
ACCRETECH SBS UK, Ltd. has been developing solutions to increase the accuracy and efficiency of the grinding process for over 25 years in collaboration with grinding machine manufacturers, retrofitters and end users.
SBS balancing technology ensures a smooth run
The fully automatic SBS balancing system is integrated in the grinding machine as an in-process control. It permanently monitors the unbalance and signals any necessary rebalancing to the machine control. The balancing process is started by the machine or by pressing a button and is carried out fully automatically.
ACCRETECH SBS offers various built-in (Internal) balancing heads to facilitate integration in the spindle nose: with signal transmission, power and control commands at the front or the rear of the spindle. Add-on (External) balancing heads are also available and can be assembled on the grinding wheel flange or spindle nut. The automatic External balancing heads come with either slip ring based contact type or contactless signal transmission.
Hydrokompenser fluid-balancing systems ensure fast and accurate balancing, and can be a solution for mechanically challenging machine installations. During rotation, cooling lubricant is injected into the four chambers of a ring container via automatically controlled valves, compensating for unbalance in the grinding wheels.
Acoustic sensors can be integrated in the balancing heads
Acoustic emission sensors (AE sensors) can be integrated in the balancing head to monitor the grinding process. They offer maximum sensitivity, and at the same time, are designed for use in the harsh environment of a production grinding machine. The acoustic sensors enable micron-precise spark detection between the grinding disc and the workpiece, reducing the air-grinding time (grinding before contact is made with the workpiece), also known as Gap Elimination (GE) or First Touch Detection. This can typically reduce the cycle time by 10 – 20%. During dressing of the grinding wheel, AE can be used to monitor the entire process for deviations away from normal.
SBS balancing and Acoustic Emission systems can be installed on almost any machine. They are available as a retrofit solution for end users onto existing machines, or to machine manufacturers for integration into new machines.
ACCRETECH was founded in Tokyo in 1949 and is now one of the world’s leading providers of products for precision measuring equipment and of the most modern equipment for the semiconductor industry. ACCRETECH has been established on the European market since 1989 and now benefits from a comprehensive sales and service network.
ACCRETECH SBS UK Ltd.
Regional Director Northern Europe
Unit 2, Leofric Court
Phone +44 (0) 2476 651 774
Fax +44 (0) 2476 450 456
Mobile +44 (0) 7764 960 753