Springs & uses of springs

Post on 16-Apr-2017

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Transcript of Springs & uses of springs

SPRINGSPresenting By: Kazi Sazed Salman

ID no: 111-23-130

Spring

A spring is an elastic object used to store mechanical energy. Springs are usually made out of spring steel.

When a spring is compressed or stretched (force applied), then it gets a change in length.i.e., Force or Load α Length of Spring.

Types of Springs

Helical Spring

Conical & Volute Spring

Torsion Spring

Laminated Spring

Belleville or Disc Spring

Special Purpose Spring

Helical Spring

In Helical Spring, the spring wire is coiled in the form of helix.

Compressive Helical Spring Tension Helical Spring

Conical & Volute Spring

Conical & Volute Springs have conical or angular shape.

Conical Spring Volute Spring

Torsion Spring

These types of springs remains in a torsional coil structure.

Helical Torsion Spring Spiral Torsion Spring

Laminated or Leaf Spring

Consists of a number of flat plates held together by clamps & bolts

Laminated Springs

Disc or Belleville Spring

Consists of a number of conical discs held together by a bolt or tube cylinder. Used as washer with bolts.

Disc or Belleville Springs

Special-purpose Spring

Different types & kinds of spring for using in special purposes.

Special-purpose Springs

Special-purpose Spring

Different types & kinds of spring for using in special purposes.

Air SpringsLiquid Springs

Special machine part Spring

Stress in Helical Spring

W= Load or force on springD= Diameter of spring cross-sectiond= Diameter of spring wire

σS2 = Direct Shear Stress = Load / Cross sectional area = 4W/πd2

σS1 = Torsional Shear Stress =πd3

8WD

σS = σS1 ± σS2

πd3

8WD

πd2

4W= ±

d

πd3

8WD= (1± )

2D

(+) for inner edge of the wire(-) for outer edge of the wire

πd3

8WD= (1+ 1/2c) ; [ c = d/2D ]

= K πd3

8WD; [ K = (1+ 1/2c) ]

Total Stress:

Maximum Stress on Spring: (σS)max = K

πd3

8WD

πd2

8Wc= K

Here, K is known as Wahl’s stress factor

Common Uses of Springs

Common Uses of Springs

Common Uses of Springs

Common Uses of Springs

Thank You...

That’s all from me.Hope you have enjoyed.