Trade Science, Cross Dial And Gas Laws Flashcards
The higher from sea level ________ the atmospheric pressure?
Lower
Atmospheric pressure at sea level is?
14.7 Psia
1.01bar
A vaccum occurs when the pressure in a confined space is less than the pressure around it. Perfect vacuum is?
0 Psia
-14.7 Psig
True of false:
A manometer is an accurate means of reading vacuum?
True
A compressor is working at high altitude. If you compared it to one running at a low altitude machine, the high altitude l machine would produce_____ compressed air over the same time period?
Less
If you calculated the power consumption of the compressors what machine would use more power?
High altitude compressor or low altitude compressor?
Machine at low altitude
To create flow in a compressed air system you will need a _______?
Pressure differential
If you heat gas in a confined space, the pressure will go _______ because the molecules move __________
Up
Faster
The absolute scale that works with kelvin is _______?
Kelvin
Convert 180 degrees F to C?
C=(F-32)x5/9
82
Convert 250f to K absolute? C+273
(F-32)x5/9
394
Pascals law states?
Pressure in a confined space will transmit equally in all directions
When there is constant flow in a pipe, the velocity of gas will decrease when the pipe size _______. According to Bernoulli.
Increases
Boyle’s law considers ______ as a constant?
Temperature
Charles law considers ________ as a constant?
Pressure
Guy-Lussacs law considers _______ as a constant?
Volume
When calculating any gas law you must always convert?
Both pressure and temperature to absolute
Force = mass x acceleration
If force = pressure x area, than Area = _______?
Force/pressure
The coefficient of linear expansion for carbon steel is_________F
.0000063
What is the formula to calculate the length change for metal
Original length x delta T x coefficient of linear expansion
Cross dial method uses two dials mounted _______ degrees across from each other?
180
Cross dial A reads off the ________ machine?
Fixed
What is a good reason to use cross dial?
End float does not affect readings
With horizontal cross dialling you zero the ______ oclock reading on the b dial and the ______ oclock reading on the a dial?
9
3
Bar sag is _______to the b dial?
Taken away
The x values measures the distance between the_________?
Distance between the dials
A positive reading when measuring horizontal moves would have you move the machine to the _______ when viewing the equipment from the fixed machine looking at the MTBS?
Right
Dial bar sag is applied to the?
Minuses from the b dial at the 12 o’clock
Added to the a dial at the 6 o’clock
True or false?
If you are torquing down the bolts after adding shims and you have excessive dial movement, the most likely cause is soft foot
True
True or false
When graphing a cross dial alignment you would use the A and B dial readings to plot the centreline of the machine to be moved?
True
True of false
The total indicator reading of the dials would be 1/2 of the actual shims to be added under the feet in cross dial alignment?
False
To find L1 and L2 measurements you will measure from which dial? A or B
A
S1 = 20
S2 = 39
S1 = 5.5
S2 = 17.5
Offset misalignment is measured off the:
Face
Rim
Shaft
Feet
Rim
A class D shim would have a size of “?
5x5
Plastic shims are colour coded?
True or false
True
The most common type of misalignment is?
Offset
Angular
Combination
Parallel
Combination
Misalignment can cause:
Equipment damage
Vibration
Loss of production
All of the above
All of the above
When using a dial indicator for alignment, what do you need to check for?
The dial makes contact the full 360 degree
The dial plunger does not stick
The dial in indicator moves in a positive direction when pushed in
All of the above
All of the above
When you torque the bolts on equipment what is important?
You torque to the proper ft/lb for the type of fastener
If a baseplate surface is not level for your driver, what would you look for?
Soft foot
When installing new equipment to be cross dial aligned, the machine to be shimmed should?
Be lower then the fixed machine
Jacking bolts/screws are used to?
Adjust machine to be moved horizontally and hold the machine in place when adding shims under the feet.
Plastic shims are colour coded for _______ and metal shims are classed by _______?
Thickness
Size
Soft foot can be checked with?
Feeler gauges
Laser shaft alignment
Dial indicator
All of the above
All of the above
Run out on a machine is called?
Eccentricity
Dial bar sag can occur with?
Large diameters and long spans
Small diameters and short spans
Measurements in the 12 and 6oclock
All of the above
All of the above
When you take 4 readings 360 degrees, the vertical readings should equal?
3 and 9 o’clock readings
Or
Horizontal readings
When first moving the machine for alignment you should?
Rough align the machine to .010”
The accuracy of the alignment will be affected by?
A loose sole plate
Millwright training
Rpm
Elastomeric shims can?
Correct angular soft foot
Dial bar sag is applied to the ______ when doing cross dial readings?
Both a and b dials at the 6 and 12 o’clock readings
When you can only take 3 readings around the 360 degree arc, you can ________ to perform the alignment?
Balance the vertical readings with the horizontal
When locking out the machinery that is to be aligned, you must?
Use your own locks
Have identification for the lock
Make sure the lock is properly secured
You will intentionally misalign the machine when?
There is a change in temperature of the fixed machine or the machine to be moved
To successfully align shafts you must correct which two conditions?
Angular and offset
When beginning the alignment (before you use the dials) you should first align the machine __________ before _________?
Horizontal
Vertically
Before beginning any alignment, you need to check for?
Bar sag
Soft foot
End float
Bent shafts
Misalignment may be caused by?
Poor alignment practices
Bearing wear
Thermal growth
Before soft foot is corrected, what alignment is done?
Rough
When adding shims under the machine foot, keep the number of shims to how many?
3 or 4
The foundation should be set ________ mm low so you can grout the machine base in place?
18 to 38mm
When accurate shaft alignment has been achieved, a condition known as __________ exists?
Concentricity
A base plate is used when there is a driver and driven units are made up as sets?
True or false
True
Levelling devices that are used on equipment are?
Levelling feet
Levelling screws
Adjustable mounting feet
When levelling equipment on concrete floors with leveling screws and bolts, you would use levelling washers or mounting plates which help stop the machine from moving around.
True or false
True
If you need to install anchor bolts before the concrete foundation is poured, you would _______ to properly positions the machine?
Use a template
Use reference and centre lines
Work off elevations and datum lines
The most important reference line is the __________?
Machine centre line
To find right angles for reference lines, you can?
3-4-5 triangle
Arcs
Optical equipment
When installing non expanding anchor bolts with grout or epoxy you will?
-Work out all air pockets and coat all surfaces
-Keep threads clean and protected
-Have enough length to properly secure machine
Poly metric grout is non shrinking?
True or false
True
Grout used for filling anchor bolt holes or filling voids under baseplates has a mix of?
1 part cement
2 parts sand
No aggregate
Water(fluid consistency)
Cement based grout can be worked on in______ days and reaches full compressive strength after ________ weeks?
7 days
4 weeks
After alignment and levelling of equipment, you should torque hold down bolts to _______ % before grouting?
50 %
A disadvantage of synthetic grout is?
Usuable time is only 30 min to an hour
To eliminate air pocket and voids under the base you can?
Use fine aggregate free grout and drill two holes, one with a grease nipple and add grout with a grease gun
Anchor bolts that are used on equipment with high vibrations and not grouted in place are the _______?
Boxed
Straight anchor bolt should be installed to a depth of_______ while a bent anchor bolt should have a bent length of ________?
25 times the diameter
4 times the diameter
Adhesive anchor bolts have the advantage of _________ over expansion bolts and sleeves?
Can be used near edges
Close centres of anchor bolts
No creep during vibration of loads
Soleplates are brought to a minus elevation of _________ for transmission and drive units?
3 to 5 mm
Primary units are accurately brought up to their required elevations.
True or false
True
When grout is to be applied to the surface of a concrete slab, you need to make sure the slab surface is?
Roughened with a needle scaler
Dampened (for cementious grout)
Free of oil and chemicals
Fowl diameter is __________ for indirect drive equipment.
Size in size of the the hood down bolts
The physical states of matter are?
Liquid
Solid
Gas
Cohesion is the attraction of like molecules. What is a good example of a strong cohesion and a weak cohesion?
Steal is a strong cohesion
Water is weak cohesion
Stress is equal to force_______ area, and strain is equal to extension ________ length.
Stress = force / area
Strain = extension / length
Ductility is the ability of a material to stretch and maintain a new shape, an example of this is?
Drawing a material through a die
For every 150 degree F change in temperature of steel will equal _______ length change per inch of material diameter.
.001”
In the galvanic series, iron and steel can be corroded by which of the following:
Silver
Nickle
Brass
All of the above
All of the above
To measure high temperatures up to 2400 degrees F, you would use a ________?
Resistance thermometer with and ohmmeter measuring electrical resistance.
Thermocouples with a voltmeter measuring voltage
Heat transfer by conduction allows the heat to transfer directly thru that material, such as a bearing being heated on a hot plate.
True or false
True
A body at rest will stay at rest and a body in motion will remain in motion at the same speed and direction if no force acts upon it. This is an example of newtons _______ law?
1st
Velocity = distance/time
True or false
True
The heat from a hydraulic system would be a sign of loss of efficiency. This would be an example of?
Conservation of energy
1HP = ?
746 watts
550ft.lbs/s
When using laser alignment equipment you would mount the transmitter on the _________ machine?
Stationary
The reflector shoots the beam back to the transmitter and any Change in the position of the reflected beam from the original spot it was projected from the detector is misalignment.
True or false
True
Most laser systems require that the laser unit and shafts rotate together, some only need as little as ___________ degrees of rotation?
60 to 70 degrees
Laser beams are either class 1(invisible) or class_____?
2 visible
The lasers should be protected from______, as this will cause beam distortion and inaccurate readings.
High heat
Steam
Laser detector calibration can be checked, can the unit be re Calibrated?
No
Which of the following is not a measurement that is imputed into the laser unit?
Laser to prism
Laser to coupling centre
Rpm
Laser to front foot
Laser to front foot
When doing a laser bore alignment on an engine block crank journal, you will centre the laser at the bore at one end and centre the target sensor with support rods at the other end. Move target sensor to each bore and record readings. Rotate is 180 degrees to check for horizontal offset and angularity and adjust bore alignment
True
The main advantage of laser alignment over wire alignment is ?
Much faster
