Chains Flashcards

0
Q

Power transmission chain

A
  • used as a positive drive to transmit power between widely spaced shafts
  • 98% efficient
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

Number one reason for chain wear?

A

-lubrication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Two types of Pre-lubricated chain

A
  • sintered bushing

- o ring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Sintered bushing

A
  • Bushings are charged with lubricant that is squeezed out when chain is under load
  • has no roller
  • lasts 5 times longer
  • 10% less loading capacity than standard chain
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

O-ring

A
  • intended to provide lifetime lubrication and to exclude contaminants. 10 times cleaner than without for food places
  • stronger than standard chain but 5% less than sintered
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Oilfield chain

A
  • multiple strand chain that is made to ANSI dimensions and upgraded to API standards
  • uses press fit instead of slip fit
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Types of chain

A
  • roller

- silent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Roller less chain

A
  • designation #5
  • run in sheaves instead of sprockets
  • maintain tension where there is no or very little movement
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Silent chain (timing chain)

A
  • Consists of links made up of tooth side plates
  • highest efficiency
  • high speed
  • widest range of speeds
  • widest range of load
  • compact
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

3 silent chain designs

A
  • side guide
  • centre guide
  • duplex/serpentine drive
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What tools do you need for sprocket alignment

A

-straight edge and feeler gauge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Chain wrap

A

-chain climbing up the back of the sprocket caused by too little tension

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Appropriate chain tension

A
  • slow to med 4-6% sag

- high speed or vertical drive 2-3% sag

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Double Pitch

A
  • same as standard chain but the pitch is double.

- used for long spans and low speed, low horsepower

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Master Clip installation

A
  • closed end in the direction of travel

- remember trailing edge (end with split) is the back edge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

slip fit side plate

A

-reduces the working capacity of the chain by 30%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

press fit side plates

A

-do not reduce working capacity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Too much chain tension

A
  • will prevent lubrication from getting all around the shaft

- put undo pressure on the shafts, etc…

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Chain lubrication

A
  • apply to inside of slack span
  • low speed drives (under 600 ft per min) use manual or drip feed
  • chains at 1500 ft per min use bath lubrication
  • forced (oil pump from above)
19
Q

Elongation

A

-over 3% and the chain should be changed

20
Q

Galled

A

-Metal has been torn away from the surface of the pin

21
Q

Backstop

A
  • restraining device that prevents the load from turning the drive when the drive is shut off.
  • one way clutch is often used
22
Q

Minimum chain wrap angle

A

-120 degrees

23
Q

Double strand chain

A
  • 1.7 times stronger than single strand
  • side plates are press fit, but centre plates are slip fit
  • higher load and speed capacity
24
Heavy Duty
- does NOT have a higher load capacity, but lets it last longer - has thicker side plates
25
Single pitch offset link (half link)
- reduces the length of the chain by one pitch | - consists of two bent side bars that are riveted to a bush and roller at one end
26
Most common light duty chain
- #41 | - has 1/4 wide rollers
27
Hunting Link
- used when an odd number of pitches is required | - offset link
28
Joining pin or connecting link
- used to change the chain length by two pitches | - convenient for assembling the chain in the field
29
Chain Length
- 1/2 the total sprockets times the pitch which represents the length the chain will wrap around the sprockets - then double the drive centre distance.
30
To order new sprockets
-you need to provide chain pitch, chain type, number of strands and hub style
31
Bushing Failure
- Caused by overload - sprockets too small - imperfect form on the sprocket teeth - badly worn or oversized gullet on the sprocket teeth
32
Roller Failure
-Caused when the sprocket repeatedly engages the sprocket teeth under load
33
Stretch
- One way a chain can be elongated | - could jump off the sprocket
34
Pin Failure
- From constant flexing of the pin as each chain link moves over the sprocket. - exposure to corrosives
35
Side Bar Failure
-Repeated stressing and unstressing of the chain as the links moved from the loaded and unloaded strands
36
Ways to improve service life on driver to driven
- increase centre distance | - change the speed in two steps using a jack shaft
37
Idler Sprockets
- used as chain tensioner - to prevent chain whip - improve chain wrap - to provide reverse rotation of a sprocket outside the chain
38
Idler Sprockets mount?
-on the slack span to reduce wear on the chain and sprockets
39
Hub Style A
-flat sprocket that can mount on any hub
40
Hub Style B
-Hub on one side
41
Hub Style C
-hub on both sides
42
Hub Style D
-split in the middle so you can mount it between bearings without having to remove them.
43
Sheer Pin Hub
- Provides the sprocket drive with overload protection in case of a jam - shears off with too much force - Uses Type A sprocket
44
Sprocket
-toothed wheel designed to mesh with power transmission chains
45
Installing sprocket
-there should be .002-.005 clearance between the top of the key and the sprocket -none on the sides (some applications allow .002 -
46
Sprocket runout
-.002