Wednesday, 19 June 2013
Understanding Required Balancing Tolerances
The following drawing defines the required balancing tolerance according to ISO 1940/1.standards:
NOTE: The table in my previous blog defines the required balancing quality G according to each rotor type.
The maximum service speed is reported on the horizontal x axis , while the acceptable specific unbalance (acceptable unbalance per unit of mass or acceptable residual mass eccentricity ) is reported on the vertical y axis.
The following formula can be used instead of the previous diagram:
Where: Et  = total acceptable mass eccentricity
N [RPM] = Maximum service rotor speed
G [mm/s] = Balancing quality or grade
Total residual accepted unbalance: U [gr∙mm] = Et∙M
where: M [kg] = Rotor mass
Total residual admitted unbalance in grams is where R [mm] is the compensation radius.
This is all very technical stuff and most likely, only of interest to a very small number of people who enjoy the complexities of balancing as much as myself!
If you would rather leave the formulae to the experts then why not have a chat with a balancing machine expert at Cemb Hofmann UK.
Call us today on 0161 872 3123 and we will be delighted to assist you with whatever area of unbalance you are experiencing with your rotating parts.