Alignment Flashcards
This alignment method uses two dial indicators mounted 180 degrees across from each other
Cross dial method (shafts must rotate together)
Before using the cross dial method what type of alignment should you use
Rough alignment to ensure the dial plunger makes contact with coupling rim a full 360 degrees
Whats an advantage of cross dialing over rim and face
End float does not effect it due to no face readings
In cross dial alignment what should the distance be between dials
4 times the shaft diameter (minimum)
Where are the A and B dials set up using the cross dial method
‘A’ Dial is on the fixed coupling at 12 o’clock
‘B’ Dial is on the MTBS coupling at 6 o’clock
How should the dials be mounted in cross dialing
180 degrees and perpendicular to the surface they are measuring from
What is the validity rule?
The sum of 3 and 9 o’clock must add up to the sum of 6 and 12 o’clock before bar sag is accounted for
What is the rule of thumb when using jacking bolts
The dial nearest to the MTMB affects the front feet, and the dial furthest from the MTBM affects the back feet. (Near-Near, Far Far)
How is bar sag calculated
Add sag to Dial A, Subtract sag to Dial B
Positive readings are _____ the datum, negative readings are ____
Towards, away
How much is 1 mil
0.001 inch
What should you do before making corrective shims on the MTBS
Place the dials and brackets at the 3 and 9 position and set to zero as well as make sure the jacking bolts are just touching the side of the MTBS
The dials always indicate ___ times the misalignment at the dial plane
two times
What is the maximum amounts of acceptable error after the alignment is finished called
Misalignment limits
What are the maximum offset parallel and maximum angular misalignment?
Maximum offset parallel misalignment: +-0.002” @1800rpm
Maximum angular misalignment: +-0.0002” @1800rpm
In this type of cross dialing both dial indicators are in the 12 o’clock position
Reverse reading alignment
The accuracy decreased when the distance between dial indicators is less than this
4”
How should shim changes be made
Loosen hold down bolts one leg at a time
Which is the fixed unit?
The driven unit
What does Laser stand for
Light Amplification by Stimulated Emission of Radiation
What are the three basic types of laser alignment
Single reflected beam with a single detector
Dual beam with dual detectors
Single beam with dual detectors
What is dynamic interruption
Occurs when the beam falls outside the range of the detector while rotating the coupling. It allows you to readjust the beam back without starting over
Which types of laser alignment does not allow for dynamic interruption
Dual beam dual detector
What are the key laser components
Transmitter or detector unit
Reflector
Bracket
What do you use to to maintain accurate and consistent repositioning of the shafts at the clock locations with laser alignment
An inclinometer
Newer laser systems have an operating range of up to
10m (33ft)
What can cause inaccurate readings for laser units
Strong heat or steam sources
On most laser systems the units require the _____ to the on the stationary machine and the _______ to be on the MTBM
Laser, reflector
In laser alignment what do you use to maintain accurate and consistent repositioning of the shafts at the locations
An inclinometer
