chain drive advantages disadvantages and types in detail

1. chain drive

2. • Chain drive is a way of transmitting mechanical power from
one place to another. It is often used to convey power to the
wheels of a vehicle, particularly bicycles and motorcycles. It is
also used in a wide variety of machines besides vehicles.
• Most often, the power is conveyed by a roller chain known as
the drive chain or transmission chain, passing over a
sprocket gear, with the teeth of the gear meshing with the
holes in the links of the chain.

3.  The chains, on the basis of their use, are classified into the
following three groups :
 1. Hoisting and hauling (or crane) chains,
 2. Conveyor (or tractive) chains, and
 3. Power transmitting (or driving) chains.

4.  These chains are used for hoisting and hauling purposes. The hoisting and hauling chains
are of the following two types :
 1. Chain with oval links. The links of this type of chain are of oval shape, as shown in Fig.
The joint of each link is welded.
 The sprockets which are used for this type of chain have receptacles to receive the links.
 Such type of chains are used only at low speeds such as in chain hoists and in anchors for
marine works.

7. Roller chain drive

10. Inverted tooth chain drive

11. 1. As no slip takes place during chain drive, hence perfect velocity ratio is
obtained.
2. Since the chains are made of metal, therefore they occupy less space in
width than a belt or rope drive.
3. The chain drives may be used when the distance between the shafts is
less.
4. The chain drive gives a high transmission efficiency (upto 98 per cent).
5. The chain drive gives less load on the shafts.
6. The chain drive has the ability of transmitting motion to several shafts
by one chain only.

12. • The production cost of chains is relatively high.
• The chain drive needs accurate mounting and careful
maintenance, particularly lubrication and slack
adjustment.
• The chain drive has velocity fluctuations
especially when unduly stretched.

13.  Following are the various important factors upon which the selection of a Chain and Sprocket
Wheel depends:
 1. Power to be transmitted,
 2. Speed reduction ratio
 3. Speed of the driving and driven shafts
 4. Method of lubrication
 5. Load capacity
 6. Centre distance between the shafts,
 7. Positive drive requirements,
 8. Shafts layout,
 9. Space available, and
 10. Service conditions.

14.  The chain drive requires lubrication for six purposes.
 1. To resist wear of the pin-bushing joint.
 2. To cushion impact loads.
 3. To dissipate any heat generated.
 4. To flush away foreign materials.
 5. To lubricate chain-sprocket contact surfaces.
 6. To retard rust or corrosion.

15.  Types of lubrication for chain drives
 Manual or drip lubrication (Type A)
 Oil should be applied periodically between the chain link plate edges with a brush,
spout can, or drip lubrication.
 Oil bath or oil slinger (Type B)
 With bath lubrication the lower strand of chain runs through a sump of oil in the
drive housing. The oil level should reach the pitch line of the chain at its lowest point
while operating. Only a short length of chain should run through the oil.
 Oil Stream Lubrication (Type C)
 This type of lubrication is required for large horsepower, high speed drives. An oil
pump should be provided to spray the oil across the lower span of chain in a
continuous stream.