Dynamic balancing G-grades are a quality standard that refer to the classification of the level of allowable residual imbalance of a rotor type within a particular system to guarantee optimal operation. Also referred to as the balancing tolerance, they are shown in the table below where the increasing number means a less restrictive standard. The number itself refers to the allowable maximum vibration velocity of the rotating component.
Typically, most industrial equipment is balanced to G 6.3 however we often balance items to G 2.5, G 1.0 or even G 0.4 depending upon the application and customer requirements.
Our CEMB Hofmann dynamic balancing machine allows us to balance items up to 1500 kg in weight for maximum machine performance and bearing life. We balance all impellers as standard procedure when repairing fans, pumps & motors and also balance single items for customers who are rebuilding their own machines or batches for OEMs.
When you come to us for your balancing requirements be assured you are in safe hands! Call us on 0121 526 5070.
Balancing Quality G Grade (mm/s) | Example of Rotor Type |
G 4000 | Crankshaft drives for large, slow marine diesel engines (piston speed below 9 m/s), inherently unbalanced |
G 1600 | Crankshaft drives for large, slow marine diesel engines (piston speed below 9 m/s), inherently balanced |
G 630 | Crankshaft drives, inherently unbalanced, elastically mounted |
G 250 | Crankshaft drives, inherently unbalanced, rigidly mounted |
G 100 | Complete reciprocating engines for cars, trucks and locomotives |
G 40 | Cars: wheels, wheel rims, wheel sets, drive shafts Crankshaft drives, inherently balanced, elastically mounted |
G 16 | Agricultural machinery Crankshaft drives, inherently balanced, rigidly mounted Crushing machines Drive shafts (cardan shafts, propeller shafts) |
G 6.3 | Fly-wheels Fans Aircraft gas turbine rotors Electrical armatures Process plant machinery Pump impellers Aircraft gas turbines Centrifuges (separators, decanters) Electric motors and generators (of at least 80 mm shaft height), of maximum rated speeds up to 950 r/min Electric motors of shaft heights smaller than 80 mm Turbo chargers Gears Machinery, general Machine tools Paper machines Process plant machines Water turbines |
G 2.5 | Machine-tool drives Computer drives Turbo compressors Small electric armatures Electric motors and generators (of at least 80 mm shaft height), of maximum rated speeds above 950 r/min Gas turbines and steam turbines Machine-tool drives Textile machines Turbine-driven pumps |
G 1.0 | Grinding machine drives Audio and Video drives Textile bobbins Automotive turbochargers |
G 0.4 | Gyroscopes Disk-drives Spindles and drives of high-precision applications |