Soft Foot DiagnosisSoft Foot Diagnosis&&

The Soft Foot The Soft Foot WizardWizard

Detection vs. CorrectionDetection vs. CorrectionDetection vs. CorrectionDetection vs. Correction

The amount of Soft Foot detected

does not equate

to the required Soft Foot correction!

Some Types of Soft FootSome Types of Soft FootSome Types of Soft FootSome 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.)

Some Types of Soft FootSome Types of Soft FootSome Types of Soft FootSome Types of Soft Foot

Three types:

Short foot rocking soft foot: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:Even Rocking soft foot:

Inward tapers under both diagonally opposite soft feet.

High Foot rocking soft foot:High Foot rocking soft foot:

Outward tapers under both diagonally opposite soft feet.

Larger soft foot value on foot nearest the high foot.

Rocking Soft FootRocking Soft Foot (highest values diagonally opposed)(highest values diagonally opposed)

Soft Foot DiagnosisSoft Foot Diagnosis

The typetype 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.

Diagnostic ProcessDiagnostic ProcessDiagnostic ProcessDiagnostic Process

Number inside circle represents a laser soft foot reading.

12

106

3

Number in parentheses represents a shimming correction to make.

20 (Step Shim)

16 16

8 8

Numbers in the corners of each foot represent feeler gauge value of the air gap measured.

25 25

0 0

Arrow represents direction of taper of airgap, from highest to lowest.

Rocking Soft FootRocking Soft FootRocking Soft FootRocking 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 can’t bend any more. Then, if you continue tightening the anchor bolt, you’ll either break the foot off, or distort the rest of the machine frame. If the foot does not break off...

Rocking Soft FootRocking Soft FootRocking Soft FootRocking 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.

Rocking Soft FootRocking Soft FootRocking Soft FootRocking 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...

Rocking Soft FootRocking Soft FootRocking Soft FootRocking Soft Foot

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

12

14 1

2

1515

15 15

15

12

12

9

15

Short Foot Rocking Soft FootShort Foot Rocking Soft FootShort Foot Rocking Soft FootShort 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.

Induced Soft FootInduced Soft FootInduced Soft FootInduced 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.

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.

Induced Soft FootInduced Soft FootInduced Soft FootInduced Soft Foot

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

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 Soft FootThe Soft Foot

WizardWizardThe Soft FootThe Soft Foot

WizardWizard

It has a high resolutionhigh resolution sensor for accurate detection.

It will diagnosediagnose the problem and suggest a solution for it.

Laser Alignment SystemsLaser Alignment SystemsLaser Alignment SystemsLaser Alignment Systems

Rotalign Ultra is ideal forRotalign Ultra is ideal forsoft foot because:soft foot because:

Diagnosis: Example with LaserDiagnosis: Example with LaserDiagnosis: Example with LaserDiagnosis: Example with Laser

Example DiagnosisExample DiagnosisExample DiagnosisExample Diagnosis

Example Diagnosis:Example Diagnosis:Rocking Soft Foot foundRocking Soft Foot found

Example Diagnosis:Example Diagnosis:Rocking Soft Foot foundRocking Soft Foot found

Diagnosing the SolutionDiagnosing the SolutionDiagnosing the SolutionDiagnosing the Solution

Diagnosing the SolutionDiagnosing the SolutionDiagnosing the SolutionDiagnosing the Solution

Diagnosis & Solution FinishedDiagnosis & Solution FinishedDiagnosis & Solution FinishedDiagnosis & Solution Finished

Diagnosing the SolutionDiagnosing the SolutionDiagnosing the SolutionDiagnosing the Solution

An Angled Soft Foot Problem

Diagnosing the SolutionDiagnosing the SolutionDiagnosing the SolutionDiagnosing the Solution

An Angled Soft Foot Problem, cont.

ConclusionsConclusionsConclusionsConclusions

Soft Foot diagnosis & correction is always a challenge.

Consistently accurate Soft Foot diagnosis is possible.

RotalignRotalign®® Ultra Ultra makes this a breeze!

Thank you!Thank you!Thank you!Thank you!

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