Soft Foot Diagnosis

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• Soft Foot DiagnosisThe Soft Foot Wizard

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Detection vs. Correction

• The amount of Soft Foot detecteddoes not
  equateto the required Soft Foot correction!

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Some Types of Soft Foot

• Rocking (Highest values diagonally opposed.)
• Angled (Bent foot bowed baseplate, angled
  soleplate.)
• Squishy (Too many shims, dirt, etc.)
• Induced (External forces Pipe strain.)

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Some Types of Soft Foot
Rocking Soft Foot (highest values diagonally
opposed)

• Three types
• Short foot rocking soft foot
• Parallel airgap under foot with largest soft foot
  reading.
• Tapered airgap (inwards) under diagonally
  opposite foot.
• Even Rocking soft foot
• Inward tapers under both diagonally opposite soft
  feet.
• High Foot rocking soft foot
• Outward tapers under both diagonally opposite
  soft feet.
• Larger soft foot value on foot nearest the high
  foot.

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Soft Foot Diagnosis

• The type of soft foot can usually be determined
  by comparing the measured values.
• Different types of Soft Foot yield different
  combinations of values.
• Diagnosis and correction is expedited by
  recognizing the type of soft foot problem, then
  seeking appropriate additional data required to
  solve it.

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Diagnostic Process
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Rocking Soft Foot
Imagine this condition on your machine. The front
right foot is short. If you tighten the anchor
bolt, the foot will bend until it cant bend any
more. Then, if you continue tightening the anchor
bolt, youll either break the foot off, or
distort the rest of the machine frame. If the
foot does not break off...
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Rocking Soft Foot
Suppose the short foot is now tight to the base.
The frame is distorted and under stress. How will
that stress relieve itself as you loosen each of
the anchor bolts in turn, always with the others
tight? Obviously, the short foot will come up as
fast and as much as you allow it to, if you
loosen its bolt.
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Rocking Soft Foot
On the other hand, if the short foot is tight,
the opposite corner (the back left foot) will
also come up if you let it. So the machine
rocks diagonally. Now imagine for a moment what
the air gaps under each of these feet will look
like, if you loosen these feet...
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Rocking Soft Foot

• Laser system indicates Soft Foot values greater
  than 2 mils at diagonally opposite corners.

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Short Foot Rocking Soft Foot
Please view our QuickTime video on rocking soft
foot in action... Available as a separate
download from our Learning Center page.
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Induced Soft Foot

• Laser tools will show soft foot values on two,
  three or even all four feet of the machine. The
  two highest values tend to be along the same side
  or the same end of the machine frame.

• The distribution pattern of the values does not
  match any angled soft foot patterns.

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Induced Soft Foot

• Laser tools will show soft foot values on two,
  three or even all four feet of the machine. The
  two highest values tend to be along the same side
  or the same end of the machine frame.

If you suspect pipe strain, the Optalign Smart
will let you check for that and quantify its
impact on the shaft alignment, so you can take
this information to the pipe fitters as proof of
the problem...

• The distribution pattern of the values does not
  match any angled soft foot patterns.

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The Soft FootWizard
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Laser Alignment Systems
Rotalign Ultra is ideal forsoft foot because

• It has a high resolution sensor for accurate
  detection.
• It will diagnose the problem and suggest a
  solution for it.

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Diagnosis Example with Laser
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Example Diagnosis
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Example Diagnosis Rocking Soft Foot found
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Diagnosing the Solution
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Diagnosing the Solution
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Diagnosis Solution Finished
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Diagnosing the Solution

• An Angled Soft Foot Problem

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Diagnosing the Solution

• An Angled Soft Foot Problem, cont.

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Conclusions

• Soft Foot diagnosis correction is always a
  challenge.
• Consistently accurate Soft Foot diagnosis is
  possible.
• Rotalign Ultra makes this a breeze!

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Thank you!
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