In the assumption that the total residual unbalance is known, it is possible to calculate the corresponding value for the balancing quality G according to ISO standards 1940/1.
Example of calculation:
Rotor mass M [kg] = 6
Maximum service speed N [RPM] = 5000
Total residual unbalance U [gr mm] = 180
Total residual eccentricity E [m] = 180/6 = 30
Using the diagram featured in my recent blog post entitled "Balance quality grades for various groups of representative rigid rotors" - two lines are drawn; one line, normal to the x axis, passing through the maximum service speed value, (5000 in the example). The second line, normal to the y axis, passing through the residual eccentricity (30 in the example).
The inclined line, passing through the intersection point of the two drawn lines, defines the balancing quality (grade).
As an option, the following formula can be used:
If you would like to know more about any area of balancing - or have a specific issue of unbalance that you would like to discuss with an expert, please do not hesitate to pick up the phone and contact Cemb Hofmann UK today on 0161 872 3123 or visit our Cemb Hofmann UK Website now.
Cemb Hofmann is the UK specialist in static and dynamic balancing - manufacturing high precision and highly accurate static and dynamic balancing machines as well as a highly acclaimed sub contract dynamic balancing service.