3: Equipment & Accessories Flashcards
What are the 3 most important factors in when it comes to sensitivity level?
- Field strength & direction
- Current level & type
- Control of particles
Too low of current produce what?
Leakage fields that are too weak to properly form indications
AC is best for what?
Keeping particles moving
What type of powder and current is better for subsurface discontinuities?
Dry powders w/ half wave rectified AC or half wave DC
Our eyes are most sensitive to what application?
Wet continuous fluorescent
Describe the voltages and amps in a Step Up transformer:
Volts up, amps down
Describe volts and amps in a Step Down transformer:
Volts down and amps up
best for MPI
What do amps measure?
Current
What do volts measure?
Pressure
What does the “tap” setting change?
Amperage
What concentration of particles is allowed for visible magnetic particles?
1.2-2.4 mL per 100 mL vehicle
What concentration of particles is allowed for fluorescent particles?
0.1-0.4 mL per 100 mL vehicle
Amperage of DC depends on what?
Thickness of the part
Amperage of indirect current depends on what?
L/D ratio
A stronger magnetizing field will be in what size of diameter (given the same amount of amperage)?
Smaller diameter
How do you figure out if you have enough amps?
QQI, Pie or Gauss gauge
For AC, how much weight is the yoke required to lift in a dead lift test?
10 lbs
For DC, how much weight is required to lift for a dead lift test?
30-40 lbs
Longitudinal fields all have to be what?
Indirect
What are 4 examples of a longitudinal magnetic field?
- Coil
- Coil wrap
- Yoke
- Permanent magnet
What is the formula for a low fill centre conductor?
Diameter of centre conductor + 2x and wall thickness x 20 amps
For DC current, and yoke legs spaced 4-6” apart, how much weight is the minimum it is required to lift?
50 lbs (23 kg)