303 Ha And Hb Flashcards
Triangle of undercarriage ?
Traction
Stability
Load carrying capacity
What kind of track pads are used to minimize undercarriage wear?
Narrowest track pads possible for job application
Undercarriage machine applications?
Crawler tractors
Excavators and shovels
Cranes
Undercarriage system components?
Track frame
Pivot shaft/equalizer bar(hard bar)
Track chain link assembly
Track and carrier rollers
Idlers
Track tension and recoil mechanism
Protective guards
What is the track frame?
Rigid structure undercarriage component are mounted too
What is a fixed track frame?
Rigid design and connected directly to machine. Increases machine stability. Lower operator comfort level
Oscillating track frame?
Uses equalizer bars and braces to let the track frame walk over unravel ground separate from the other frame and machine
Track chain construction?
Links
Pins
Bushings and seals
What’s the split master link?
Provides and easy method for uncoupling the track chain. Uses a tooth joint and long bolts to connect the half links together
What are standard pins?
Constructed of heat treated steel and hardened steel. The are slip fit into bushings and mounted into the small end of the track chain
What is the master pin?
Tracks that do not use master links will use the master pin. Can be identified by the slight recess on end of pin and is slightly smaller in diameter
What is a lubricated track?
Sometimes called a sealed and lubricated track (SALT). Pin and bushing is sealed and rides on a small amount of oil. Quieter operation and lasts longer when maintained properly
Flush type track link configuration ?
Used with the master pin. Makes uncoupling the track a lot easier compared to interlocking. Downside is it has a increased chance of contamination
Interlocking type track link?
Design still allows pivoting action to occur but reduces the amount of contamination having the bushing and pin press fit into the links
Track shoe configurations?
Standard grouser
Open centre grouser
All purpose ( multi grouser/ street pads)
Rubber
Specialty shoes
Low sprocket design?
Traditional low mounted final drive. Lowers the centre of gravity. Increased stability.
High sprocket design?
Reduces the effect of shock loads. Downside is they have increased internal pin and bushing wear because of a third track chain pivot
Track and carrier roller configuration?
Pedestal carrier rollers
Track rollers
Vogue style track rollers
What are pedestal carrier rollers?
Support the weight of the track.
Track rollers?
Supports the weight of the machine on the track. Transmits shock loads from the track to the frame
Bogie style track rollers?
Group of independent pivoting track rollers are used in place of a single track roller. Provides track contact over uneven ground
What is the roller shell?
Larger outer structural member of any roller assembly
2 types of roller shells ?
Single flange
Double flange
Things to fix during track maintenance?
Track tension
Loose, damaged or missing components
Evidence of misalignment
Roller/idler leakage
1 spot to see misalignment on an undercarriage?
Sprocket
Evidence of misalignment?
Unusual roller flange wear from side hilling
What must you be careful to watch when measuring track link wear?
To not measure with master pin in measurement
How to measure drive sprocket tooth wear?
Measure three teeth apart on the sprocket. As the distance decreases the sprocket becomes more worn
Low final drive front idlers must be what when installed?
Shimmed for alignment
Can worn pins and bushing be turned to increase their service life?
Yes, once
