The document discusses the design and analysis of a semi-elliptic leaf spring used in Eicher medium commercial vehicles, detailing its structure, function, and advantages. Leaf springs are crucial for supporting vehicle weight, maintaining tire grip, and ensuring load stability. The document also covers types of leaf springs, material selection, and design calculations specific to Eicher's specifications.

1. 19M501-DESIGN OF MACHINE ELEMENTS
DESIGN AND ANALYSE A SEMI ELLIPTIC LEAF
SPRING FOR EICHER MCV
Presented by
23M908 Manoj kumar
23M911 Ram Kishore
23M921 Marimuthu
23M922 Akash rishi

2. Eicher (medium commercial vehicle)
 Eicher medium duty vehicles (GVW) ranges
from (8-18tons )
 Similar vehicle models (2110,2110XP,2114
etc…)
 The vehicle is equipped with Semi elliptical
laminated leaves.

3. What is leaf spring?
 Leaf spring is a type of spring used in heavy automotive vehicles and the
suspension made up of different-sized layers of steel sandwiched on top of each
other.

4. IMPORTANCE OF LEAF SPRING
 They are installed to help support the entire weight of your truck
 Leaf springs also help to maintain the tire’s grip on the road and regulate the
wheelbase lengths when it is speeding up or slowing down.
If the load or weight of the vehicle is too high, the vehicle/trailer may start
bouncing more or swaying from side to side.
 Leaf springs are a great way to keep towed loads stable and ensure the load
stays on the ground.

5. TYPES OF LEAF SPRING
 Multi-Leaf Spring
 Mono Leaf Spring
 Semi-elliptical Leaf Spring
 Quarter-Elliptical Leaf Spring
 Three-Quarter Elliptical Leaf Spring
 Full-elliptical leaf spring
 Transverse Leaf Spring

6. SEMI ELLIPTICAL LEAF SPRING
Semi elliptical leaf spring is one of
the types of leaf spring which is
widely used in heavy vehicles for
rear suspension.
The upper leaf is known as master
leaf
The other leafs under master are
known as graduated leafs

7.  All the leafs and rear axle is hold together with the help of U – bolt.
One end (eye) is connected to the frame and other end is connected to the
shackle.
The shackle can rotate to compensate the deflection of leaf spring
The rebound clips are used, which holds the master leaf and graduated leafs
together. Hence, the stresses are distributed over the complete length of each
leaf.
The stresses due to bearing load are distributed over the complete length of
each leaf and it has the ability to withstand the higher working load.

8. NIPPING OF LEAF SPRING
 Nipping is method to apply pre-stress on graduated leafs for sharing of load
equally.

9. ADVANTAGES
 It can work for heavy load.
 It absorbs vibration due to irregular road surfaces and provides the comfort ride.
 It keeps the vehicle tires in contact with the road on the irregular road surface
APPLICATIONS
 Trucks
 Buses
 Trains

10. DESIGNING OF LEAF SPRING
 Material selection:
• The most commonly used material for leaf spring manufacturing is plain carbon
steel (C1074)
• The carbon content ranges from (0.9 to 1%)
Design calculation:
Specification of Eicher (MCV)
• When n = 10
• No of leaf springs = 4
• Overall length of spring = 2L = 137.2 cm = 1372mm
• Width of leaves = 76.8 = 80mm
• No of full length leaves (Nf) = 2
• No of graduated leaves (Ng) = 8

11. • no of springs = 10  (Ng+Nf)
• Center load = 2W=115 tones = 11500kg
• 2W = 11500 * 9.8 = 112700N
• 2W = 112700/4 = 28175N
• 2W = total load no of springs = 28175N
• W = 14087.5N