Mechanics Quiz Belts

Question 1

What are the 3 basic classifications of belts?

Answer 1

Flat
V
Synchronous(Toothed)

Question 2

Which component is driven by the belt?

Answer 2

Pulley

Question 3

What is the driving “pulley” for flat belts?

Answer 3

Drum

Question 4

What is the driving “pulley” for V belts?

Answer 4

Sheave

Question 5

What is the driving “pulley” for Synchronous belts?

Answer 5

Sprocket

Question 6

What are the advantages to belt drives?

Answer 6

•Inexpensive to install/maintain
•Reliable
•Simple design
•Easy to install
•No lubrication
•Wide variety of applications
•Adjusted for nearly any speed
•Pulleys are less expensive than chain sprockets
•Long pulley life
•Act as a clutch

Question 7

What is the primary benefit to flat belts?

Answer 7

Have the flexibility to go around corners for special drive configurations.

Question 8

How do flat belts drive?

Answer 8

Tension

Question 9

How do V belts drive?

Answer 9

Friction

Question 10

How do Synchronous belts drive?

Answer 10

Positive Tooth Engagement (and tension)

Question 11

Which belt is ideal for low speed?

Answer 11

Flat

Question 12

Which belt is ideal for medium speed?

Answer 12

V

Question 13

Which belt is ideal for high speed?

Answer 13

Synchronous

Question 14

What part of a V belt should be your contact/friction point?

Answer 14

Sides

Question 15

How tight should a V belt be tensioned?

Answer 15

1/4in per foot of span (contact to contact)

Question 16

Which side of a V belt is the tension side?

Answer 16

The side in which the sheave is pulling

Question 17

Which side of a V belt is the slack side?

Answer 17

The side in which the sheave is “pushing”(paying off)

Question 18

What are the two base construction categories for V belts?

Answer 18

Envelope and Raw Edge

Question 19

What is the difference between Envelope and Raw Edge V belts?

Answer 19

Envelope V belts are enclosed in a rubber/fabric coating which protects from contamination and elements, Raw Edge belts are not.

Question 20

Where would we use Envelope V belts?

Answer 20

Outdoors/Harsh conditions

Question 21

When would we use Raw Edge V belts?

Answer 21

Interior/clean conditions

Question 22

How can you tell the difference between Envelope and Raw Edge V belts?

Answer 22

Raw Edge V belts have visible cords

Question 23

What is the bottom of a V belt and what does it do?

Answer 23

Cusion Rubber - Provides cord support.

Question 24

What part of a V belt is above the Cushion Rubber and what does it do?

Answer 24

Tensile Cords - Carry the load.

Question 25

Which part of a V belt is above the Tensile Cords and what does it do?

Answer 25

Insulation Rubber - Protect/Adhere to cord.

Question 26

Which part of a V belt is above the Insulation Rubber and what does it do?

Answer 26

Backing Fabric - Resist Abrasion

Question 27

How are classic V belts identified?

Answer 27

Letter Designation (A,B,C,D)

Question 28

Identify this V belt. C65

Answer 28

C - 7/8in(Classical V) 65- 65in inside length

Question 29

What is the speed range for classical V belts?

Answer 29

Fractional to 500HP

Question 30

What do double V belts look like?

Answer 30

Hexagonal

Question 31

What does X denote on a V belt?

Answer 31

The belt is cogged.

Question 32

What does a cogged belt refer to?

Answer 32

Belt with notches removed from the Cushion Rubber with the intent to increase flexibility.

Question 34

What is the difference between Classical V and Wedge V belts?

Answer 34

Wedge V belts fit deeper into the sheave and provide better contact and strength.

Question 35

How are Wedge V belts identified?

Answer 35

A number (denoting x/8in), the letter V (denoting Wedge V), and a number ending in 0 (denoting outside length with the first number(s)) The 0 at the end stands for outside.

Question 36

Identify this belt. 7VX400

Answer 36

7 - 7/8in V - Wedge Belt X - Cogged 400 - 40in outside length.

Question 37

How are Fractional Belts identified?

Answer 37

A number (x/8in denoting belt width), the letter L (denoting Fractional HP belt), and a number ending in 0 (Denoting length in inches for the outside of the belt, using the 1st number(s)) Last 0 stands for outside

Question 38

What are Fractional Belts used for?

Answer 38

Drives with 1 or less HP.

Question 39

What are banded belts?

Answer 39

V belts (either Classical or Wedge) banded together using insulation rubber and backing fabric for use in multi channel sheaves.

Question 40

Why do we use banded belts?

Answer 40

Prevent uneven slipping from using multiple single belts. Eliminating rollover tendency.

Question 41

How are banded belts identified?

Answer 41

Same as other V belts, but starting with a number and slash (x/) which denotes the amount of belts banded together.

Question 42

What is the disadvantage of Synchronous belts?

Answer 42

No slippage due to positive tooth engagement which leads to possible damage to clutch (if applicable) or other components.