Main Types Of Soft Foot; Checking And Correcting Soft Foot Conditions - Fluke 830 User Manual

830
Users Manual

Main types of soft foot

The three main types of soft foot are parallel soft foot, angular soft foot, and
induced soft foot.
Parallel soft foot
One or more feet do not reach the foundation. This usually results in the machine
leaving a gap between the foundation and the feet. This is corrected by shimming
the feet not touching the foundation (refer to Figure 7-13).
Angular soft foot
The base of the foot is at an angle to its foundation and they are only partly in
contact. In this case, suspect foot is checked with a feeler gauge and corrected
by building a custom 'shim wedge' or machining the underside of the foot (refer to
Figure 7-13).
Induced soft foot
This type of soft foot is caused by forces that are external to the machine. It can
be the result of pipe strain, machine vibrations or drastic misalignment. This type
of soft foot may be eliminated by isolating the external force from the machine.

Checking and correcting soft foot conditions

There are instances where the soft foot is a combination of two or more types.
Checking for soft foot is part of machine and job preparation.
The machine(s) to be checked is/are assumed to have four feet in an approxi-
mately square formation. If the machine has six feet, it is advisable to leave
the middle feet loose and treat the machine as a four-footed machine. Soft foot
is measured only on machine designated as movable.
Set up the product in the normal way as described in "Getting started" (starting
on page 39).
Rotate shafts to position the sensor and prism at either the 3:00 or 9:00 o'clock
position.
Enter machine dimensions then press
highlight the 'Soft foot' icon.
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Note
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