chain drives

Question 1

power transmission chains are used as a positive drive to transmit power between widely spaced ?

Answer 1

shafts the chain engages with toothed wheels called sprockets

Question 2

name some power transmission limitations

Answer 2

do not slip on overload
adequate lubrication is hard to maintain
- service life is less than that of gears

Question 2

what are power transmission chain characteristics ?

Answer 2

provide positive drive
- highly efficient 98% or better
- can be used with any distance between shaft centres
- number of shaft can be driven by a single shaft
-

Question 3

two main designs of power transmission chains used they are?

Answer 3

roller chain and silent chain

Question 4

chains are made of ?

Answer 4

hardened carbon steel
-stainless steel for corrosion
-synthtics such as nylon and various plastics
-

Question 5

two basic types of links?

Answer 5

pin links and roller links

Question 5

cotter pins are usually used on what numbers of chain?

Answer 5

80 chains and larger

spring clip retainers are used on#25 to #60

Question 6

what is a connecting link?

Answer 6

unriveted link in a chain
-consists of a pin link with pins that are drilled for cotter pins or grooved at outer ends for spring clip

Question 7

the connecting link changes the chains length by?

Answer 7

two pitches

Question 8

another name for single pitch offset link?

Answer 8

half link- changes the length of the chain by one pitch

Question 9

where is light duty chain used?

Answer 9

used on drives where space is restricted ,they have lower power ratings

Question 10

what number is the most common light duty chain its used on garage doors?

Answer 10

41

Question 11

true or false double strand chain is 1.7 times stronger than single strand ?

Answer 11

true

Question 12

what is oil field chain intended for ?

Answer 12

severe service ond rilling rigs , uses press fit centre plates

Question 13

name two types of pre lubricated chain?

Answer 13

sintered bushing chain -uses a powdered metal bushing lubricant is squeezed out under load

-0-ring chain -provide life time lubrication and exclude contaminates - can operate at high temps with special o-rings

Question 13

where are pre lubricated chains used ?

Answer 13

designed for applications that do not permit regular lubrication.

Question 14

the load capacity of a sintered chain is how much less

Answer 14

10% less than a standard chain

Question 15

What corrosion resistant material is corrosion resistant chain produced with

Answer 15

stainless steel or by plating standard chain with a corrosion resistant coating such as nickel or a zinc compound

Question 16

true or false -
Stainless steel does not have the tensile strength of carbon steel, and therefore load capacity is sacrifice for corrosion resistance

Answer 16

true

Question 17

Plated chain has the same load capacity of standard chain, but it protects the integrity of the chain in a corrosive environment. However, the corrosion protective is lost when.

Answer 17

the platting wears off

Question 18

Synthetic chains are designed for very light service. Such as instrument drives in office machines.true or false

Answer 18

true

Question 19

Where woud synthetic Chain applications be

Answer 19

food handling and process equipment
-computer equipment
-instrument drives
-

Question 19

what are synthetic chain advantages

Answer 19

light weight 15%-20% the weight of steel

• no lube required
  -all links are master links
  interchangeable with steel chain
  -corrosion resistance is good
  -

Question 20

why is double pitch chain lighter ?

Answer 20

has half the number of pins and bushing and rollers, used for long spans and slow to moderate speeds with low HP.

Question 21

instead of rollers what does roller less chain use?

Answer 21

bushings on pins at each joint -less expensive Tham standard roller chain designated by the number 5 in the right hand part of the chain number

Question 21

double pitch chains fits ?

Answer 21

standard sprockets since rollers and width are the same as standard pitch chain

Question 22

where is silent chain used?

Answer 22

transmitting high horse power in a small space such as in chain driven speed changers -high speed drives -precision timing

Question 23

silent chain is also called?

Answer 23

timing chain-contains tooth plates instead of rollers

Question 24

where is a joining pin or connecting link used?

Answer 24

used on toothed links to change the length by two pitches, convenience way for assembling the chain in the field

Question 25

where is a hunting link used ?

Answer 25

used on a tooth link when an odd number of pitches is required - an even pitch number is recommended

Question 26

what are the 3 silent chain designs ?

Answer 26

side guides centre guides for serpentine drives

Question 26

why do you do a chain inspection on a broken chain?

Answer 26

to try to discover the root cause of chain drive failure

Question 27

silent chain advantages ?

Answer 27

high efficiency and HP in a narrow width -lighter bearing load -positive drive and durability -smooth performance -load shared by a number of teeth

Question 28

how to measure the chain length?

Answer 28

measure old chain and divide by the pitch -lay new chain beside the old chain -

Question 29

the master link must be installed with the closed end of the spring clip in what direction ?

Answer 29

the direction of travel

Question 29

how do you remove old chain?

Answer 29

chain breaker -torch -grinder

Question 30

what kind of fit does a master link us?

Answer 30

slip fit

Question 31

slip fitted plate reduces the working capacity by ?

Answer 31

30%

Question 32

true or false? press fit side plates significantly reduce the capacity of the chain?

Answer 32

false .

Question 33

multiple strand chains with press fit centres plates are used in ?

Answer 33

severe service applications such as drilling rigs

Question 33

chains can be adjusted by ?

Answer 33

adjustable centres using lighting idlers

Question 34

What is the single most important factor in controlling the chains wear?

Answer 34

lubrication

Question 35

What oil should you use when lubricating chains?

Answer 35

highest viscosity and still flows into the joint

Question 36

manual drip feel lubrication is intended for ?

Answer 36

low speed drives under 600 feet per minute

Question 36

name 3 methods of chain lubrication?

Answer 36

manual or drip feed bath forced

Question 37

forced lubrication is intended for ?

Answer 37

heavily loaded drives operating above the speed limits of bath lubricaiton

Question 37

bath lubrication is intended for chains at approx ?

Answer 37

1500 feet per minute

Question 38

a warn sprocket destroys a new chain never install a new chain on a worn out sprocket

Question 39

what is a sprocket ?

Answer 39

toothed wheels designed to mesh with power transmission chains

Question 40

sprockets can be made of ?

Answer 40

allow cast iron -very large sprockets medium carbon steel- small, medium and large sprockets plastic-light duty sprockets

Question 41

where are sprockets used ?

Answer 41

-on the drive unit as idlers to tension chains -on drives that provide accurate timing -in roll cases

Question 42

what's the problem with small wrap angle ?

Answer 42

the chain may jump the teeth when operated at its designed maximum load

Question 43

the wrap angle is always 120 deg when the ratio is?

Answer 43

3:1 or less regardless of the centre distance

Question 44

a sprocket with fewer teeth results in ?

Answer 44

increases wear and vibration on the sprocket and chain

Question 45

if a chain drive does not provide satisfactory service life because a smaller sprocket is to small what would you do ?

Answer 45

increase the centre distance - change the speed using a jack shaft

Question 46

vertical and angle drives are often used were?

Answer 46

industrial drives

Question 47

sprockets with an odd number of teeth are called ?

Answer 47

hunting tooth sprockets

Question 48

what is the advantage of a double pitch chain sprocket ?

Answer 48

wear is distributed over twice as many teeth

Question 49

when ever possible use a sprocket with an odd number of teeth why?

Answer 49

different tooth engages with the chain on each revolution

Question 50

where are idler sprockets used?

Answer 50

used as chain tensioners on fixed centre drives ,they mount on slack span reduce wear on the chain and sprocket

Question 51

idlers can be used to ?

Answer 51

prevent chain whip improve chain wrap guide the chain around obstacles provide reverse rotation of a sprocket outside the chain

Question 52

hardened tooth sprockets are common and intended for greater wear resistance , they are beneficial when ?

Answer 52

the number of teeth is 20 or less on drives that are heavily loaded in abrasive conditions on high speed drives on drives that require extremely long life

Question 53

hub style sprockets type a b c d

Answer 53

a= flat plate style sprocket can be welded or bolted B= type b have a hub on one side can be mounted in smaller places C= hubs on both sides D=split design sprocket

Question 53

keyless adapters are common on machines that require what?

Answer 53

accurate timing

Question 54

tapered bore hub allows you to ?

Answer 54

use a tapered adapter bushing

Question 55

what causes side wear on a sprocket ?

Answer 55

misalignment of the sprocket

Question 56

what causes hooked teeth on a sprocket?

Answer 56

causes by wear caused by over tension inadequate lubrication abrasives or overload

Question 57

after you have tightened the pull up bolts there should be how big of a gap between the sprocket and flange ?

Answer 57

1/4-1/8 gap

Question 58

should you use more or less tension on a vertical or angle drive that on a horizontal drive?

Answer 58

more tension

Question 59

should the slack be span on the top or bottom of a drive?

Answer 59

bottom

Question 60

which sprockets would you use in an abrasive environment

Answer 60

harden tooth sprokets

Question 61

when you see a chain not meeting properly with a sprocket and is pilling up on the sprocket what's wrong

Answer 61

the chain or sprocket is worn

Question 61

what is the advantage of a b type sprocket?

Answer 61

can bemoaned closer to the support bearing