Question 4.1. Why are the rotors
balanced in situ if they are already balanced on special balancing machines?
(The question was asked by the specialists of the plant operations service of
the gas transportation enterprise in Saint Petersburg (Russia).)
The question is answered by Alexander G. Shablinsky. 21.01.99.
Question 4. 2. Sometimes during balancing it is
impossible to reduce the vibration of assembled machine on the rotation
frequency. In technical literature such result is considered as action of not
inertial oscillation forces with the rotor rotation frequency. What are these
forces?
(The question was asked by the representatives of the maintenance teams of the
petrochemical industry.)
The question is answered by Alexej V. Barkov. 21.01.99.
Question 4. 3. While balancing powerful turbines we
often face a situation when the coordinates of the heavy point and hence the
vibration of the turbine on the rotating frequency is very dependent on the load
value. A typical explanation, viz. the uneven thermal expansion of the rotating
units, does not explain the simplest experiments when a sudden change of the
load leads to a sudden change of the vibration. Then, what are the real physical
processes in such cases?
(The question was asked by the participants of the all-Russia conference "The
Problems of Vibration and Vibrodiagnostics of Equipment on Power Plants ".)
The question is answered by Alexej V. Barkov. 06.18.99.
Question 4. 4. Dear Sir, I have just accessed your
web-site and read about the DC 11 Data collector. Can you please inform what is
the minimum and maximum weight for rotors to be balanced and the accuracy of
your analyzer as well as the sales price.
(The question was addressed to the Club by a specialist in balancing.)
The question is answered by Alexander Shablinsky. 06.22.99.
Question 4. 5. I am a Professor of machine dynamics at the Alexandria University,
Faculty of Engineering. We have a VAST DC11 data collector and balancing
software.
I had a problem in dynamic balancing (2 - plane). May be I can do balancing by
the influence coefficient. I cannot do balancing by other method of trial mass
for 2 - planes. How can I do this balancing by this system . Please send me a
step by step procedure for this process.
The question is answered by Alexander Shablinsky. 05.16.2000.
