PAPER MACHINE SPEED INCREASE TRIAL

William F. Eckert, P.Eng., Ph.D.

Steve P. Lawn, P.Eng.

Senior Engineer

Beta Machinery Analysis Ltd., Calgary, AB, Canada, T3C 0J7

ABSTRACT

A large-scale speed trial of a paper machine was successfully completed using temporarily
mounted transducers and data acquisition systems. Logistical and environmental issues were
overcome to produce an understanding of the machine’s vibration behavior at future speeds, and
to shed light on ongoing vibration issues.

1. INTRODUCTION

Beta Machinery Analysis participated in a smaller scale speed trial on this paper machine in
2000. At that time, the speed of the paper machine was 1350 mpm, and the recommendations
resulting from the trial allowed the machine to be brought up to the current 1450 mpm. Based on
the success of the first speed trial, Beta was again retained by the client to evaluate the paper
machine performance at higher reel speeds. The current reel speed is between 1450 and 1460
mpm. This trial covered a speed range of 1500 to 1600 mpm, and occurred just prior to the June
2004 shutdown. It is planned to take the speed up to 1600 mpm in the future.

The job was quite challenging from an instrumentation viewpoint, as initially a large number of
rolls were identified for potential monitoring during the speed trial. After much discussion, the
number of measurement points was reduced to a manageable number, but still afforded
reasonable coverage of the paper machine. A total of 88 channels of vibration data and 6
channels of tachometer data were taken on the former, press, dryer and calender sections over the
speed range with roughly an even split of channels between drive and tending sides of the
machine. There were environmental difficulties that had to be overcome: moisture, temperature
and generally being out of the way of the day to day operations and the roll and felt change areas.

As well, during the shutdown mechanical natural frequency testing was done to determine the
possibility of resonances contributing to known vibration concerns.

The press section of this machine has a number of similarly sized rolls on a compact frame. As a
result there is significant “cross talk” between rolls. This results in a complex vibration pattern.
As well there were a number of known vibration issues in the dryer at current machine speeds
that may have been aggravated by the speed increase.