Chains Flashcards
Chain drives
Operate in tension. Teeth on driving sprocket. Higher speeds than belts because only a few sprocket teeth are required for effective engagement.
Advantages of chain drives
Versatility (can be cut to any length), variety (can make any kind you need), positive engagement (no slippage between shafts), flexibility, durability (made out of materials that can handle a lot of wear), unlimited shelf life (made out of materials that can and operate in hostile environments
Disadvantages of chain drives
Higher noise, wear out with potential of elongation, need to replace sprockets from chain wear.
Roller chain
Contains pins that pivot inside bushings. Pins are usually fit into pin link plates, and bushings are fit into roller link plates. Uses pitch to determine chain size.
Pitch
The distance between flexing joints. Larger pitch gives more load and smaller gives more speed
Connecting link
Also knows as a master link. Good for even pitches. Spring pin needs to face away from direction of motion
Offset link
Also known as a half link. Good for odd pitches. Uses a cotter pin so direction of motion doesn’t affect it
Nomenclature
Uses 1/8ths. 1=1/8, 2=1/4, 3=3/8 (etc)
0=normal
1=lightweight
2=big roller
5=rollerless
- #=that number of strands (on end)
20- - - = double pitch (on front)
H=heavy
C=conveyor
300=stainless
600=hardened/corrosion resistant
Self lube roller chain
Contain own lube supply and need no maintenance. Good where lubrication isn’t possible from contamination or no accessibility
Heavy chains
Used where space and weight limitations prohibit use of larger chain sizes. Link plate thickness is equal to the next larger chain. Good for higher shock loads
Corrosion resistant chain
Include stainless steel, nickel plated, plastic. Stainless 300 series and high resistance 600 series
Double pitch roller chain
Uses only half of driving teeth. Doubles pitch but has same load capacity as standard. Lighter and less expensive. Good for long center distances. Wears sprocket faster
