ELEMENTS OF MECHANICAL ENGINEERING

Prepared by:-

Nikul pithva(m-36)Shilay nilesh(m-37)

Guided by:-

Ravi sir

Flexible coupling and flange coupling

COUPLING

Shaft are mostly available upto 7 metres length due to transport difficulty.

To get a greater length , it is necessary to joint two or more pieces of the shaft using coupling.

FLANGE COUPLINGThis coupling is having two separate cast iron flanges as shown in fig. A unprotected type flange coupling .

Each flange is mounted on the shaft end and keyed to it.

The two flanges are coupled together by help of bolts and nuts.

The projected portion of one of the flange and corresponding recess on other flange are help to bring the shafts into line and to maintain alignment.

FIG. FLANGE COUUPLING

A FLANGE IS PROVIDED WITH A SHROUD WHICH SHELTERS THE BOLT HEADS AND NUTS AS SHOWN IN FIG. IS CALLED PROTECTED FLANGE COUPLING.THIS COUPLING PREVENT CATCHING CLOTHES OF WORKMAN.

Fig. Protected type flange coupling

This flange couplings is most accurate and rigid.

This coupling provide the strong connection of shafts.

It is used for heavy power transmission at low speed.

FLEXIBLE COUPLING

This coupling is used to protect the driving and driven machine members against harmful effects produce due to misalignment of shafts, vibration, sudden shock load or shaft expansion.

There are basic three types of flexible coupling as follows:

1) Bushed pin type flange coupling : this type of coupling allows for

imperfect alignment of two joining shafts.

2) Oldham coupling: This type of coupling is used to join

two parllel shafts with small offset.

3) Universal coupling: This type of coupling is used to join

two intersecting shaft.

1) BUSH PIN TYPE FLANGE COUPLING

Fig. Bush pin type flexible coupling

this is modified form of protected type flange coupling.

This type of coupling has a pins and it work as a coupling bolts. the rubber or leather bushes are used over the pins.

The coupling is having two halves are dissimilar in construction as shown in fig.

The pins are rigidly fastened by nuts to one of the flange and kept loose in the other flange.

This coupling is used for connection of shafts which having the small parallel misalignment, angular misalignment and axial displacement.

In this coupling rubber bush absorbs shocks and vibration during its operation.

This type of coupling is mostly used to couple an electric motor and machine.

2) OLDHAM’S COUPLING:

Fig. Oldham’s coupling

It consists of two flange A and B with slots and a central floating disc E as shown in fig.

The disc E having tongues T1 and T2 at right angles. the tongue T1 is fitted into the slot of flange A and allows horizontal sliding relative motion while the tongue T2 is fitted into the slot of the flange B and allows for vertical sliding relative motion.

This right angle motions of tongues on the slots will accommodate lateral misalignment of shaft when they rotate.

Oldham’s coupling is used in connecting two parallel shafts but not in alignment, and their axis are at small distance apart.

3) UNIVERSAL COUPLING:

These two forks are assembled to a central block by pin.

A central block having two arms at right angle to each other.

Universal coupling is used to connect two shafts whose axis intersect.

It also used to connect two shafts, where the angle between two shafts may be varied when they rotate.

The universal coupling is widely used in automobile and machine tools.

Thank you