Mechanics Final Flashcards
What are 2 forms of lubrication?
Grease and oil
Why do we use grease instead of oil?
It’s easily contained inside the housing
What are 2 types of oil?
Synthetic and petroleum
What type of lubricants are used for low speed and high temperature applications?
Dry lubricants
Definition of linear bearings?
A group of bearings that provide low friction motion in one dimension
Two ways mounted bearings lock to a shaft?
Set screw collar and eccentric
2 types of belt construction?
Raw edge and envelope
4 components of a belt?
- Cushion rubber
- Tensile cord
- Insulation rubber
- Backing fabric
Why would it be beneficial to use envelope construction?
Protects the tensile cord in the belt from the elements
2 ways to connect chains?
Master link and offset link
Advantage of extended pitch?
Cheaper, lighter used for long center to center distances from shaft to shaft
What are the 3 types of belts?
V-belts, toothed and flat
What are the 3 types of v-belts?
Classic, Fractional HP, wedge
Linear bearings consist of a fixed support component called what?
Rail, way or guide
What are seals used for?
To keep the elements out and keep the lubrication inside.
2 types of seals?
Contact and non contact
What do contact seals do?
Keep contact with the rotating and stationary components
What is an example of a non contact seal?
Labyrinth seal
What do take up units do?
Adjust the center distance between shafts or where belt tightening is required
What are the types of mounted bearings?
Pillow block (solid or split housing) flanged cartridges, cylindrical cartridges and take up units
How are flanged cartridge bearings mounted?
On a vertical surface with shaft passing through a machine frame at a right angle
Biggest advantages of drive chains?
Unlimited shelf life, durability, flexibility, positive engagement and variety
Biggest disadvantages of chain drives?
Noisey and both sprockets need changed when chain is replaced.
What keeps the connecting link pins from working loose?
Cotter pins and spring clips
Advantages of wedge belts?
Provide more contact with the sheave and puts more support in the center of the belt
Cam type & load following bearings consist of an inner and outer race with what kind of bearings between the races?
Plain or rolling element
Spherical & rod end bearings have a ball that rotates within a race to accommodate what?
A wide range of angular misalignment
What are the 3 different types of driver pulleys for v-belts, flat and toothed belts?
V-belts- sheave
Toothed- sprocket
Flat - drum style
How much deflection should you have when adjusting belts?
¼” per foot of span
Biggest advantage to belt drives?
Acts as a clutch to the system to prevent failure and they’re easily maintained
