BRIEF EXPLANATION ABOUT BODY IN WHITE.

2. CONTENTS
1. Introduction
2. Purpose of Body design
3. Classification
4. Description
5. Reinforcement
6. Factors Affecting BIW

3. Introduction
What is BIW?
BIW stands for Body in white.
A Body in white is an assembly of a frame and panels, made up of
homogeneous materials (for instance, steel or aluminum sheets or
composites).

4. A. 1)Body in white steel sheets and
2)roof panel of Fiat Stilo 3-doors,before their assembly.
B. Audi A2 aluminum body frame.

5. BIW mainly refers to:
• Body in White or BIW refers to the stage in automobile
manufacturing in which the car body sheet metal (including doors,
hoods, Trunks, bumpers and deck lids) has been assembled but
before the components (engine, chassis, exterior and interior trim
i.e. door coverings, roof liners, carpets, seats, electronics, plastic
trim parts) have been added.

6. Purpose of Body design
• Aesthetics:
To provide a pleasing overall appearance, surface quality and consistent
details.
• Structural function:
To support the weight of the transported passengers and load as well as
the mechanical parts required for vehicle propulsion, control and other
system functions, so withstanding mechanical stresses from multiple
sources.
• Ergonomy and roominess:
To supply easy access and adequate room for the driver, passengers and
transported goods.

7. • Safety:
To ensure integrity of passenger compartment in the event of a crash,
while absorbing the impact energy as well as to reduce injuries to
vulnerable road users (pedestrians, wheelers), in case of collision.
• Aerodynamics:
To minimize drag due to air impact; to control air flow effects on tyre-road
contact and vehicle stability.
• Insulation:
To minimize noise, vibration and thermal transmission, generated by body
walls, by lack of sealing between compartment and movable parts and by
thermal radiation from the surfaces of passengers compartment.
• Visibility:
To provide the highest possible day and night visibility on the environment
and to host the lighting devices in the most effective way.

8. Over view of BIW
Motor
Front
Torque Box
Compartment
Upper Rail
FBHP
(Front Body Hinge Filler)
Rocker
Upper Tie Bar
Lower Tie
Bar
Wheel
House
Shock
Tower
Roof Side Rail
Wheel House Roof Bow Rear Header / Hatch
Header Rear End Panel
C- Pillar
Body Lock Pillar
A-Pillar
Header
Plenum
Lower Rail
Dash

9. Classification
There are two kinds of body structures in use:-
1. Monocoque Body Structure
2. Frame mounted Body Structure

10. Description
Monocoque Body Structure:-
 In Monocoque Body, Chassis is in built in the BIW itself.
 And there is no separate chassis.
 Wheels are directly mounted to the BIW with the help of suspension
system.
Frame Mounted Body structure :-
 In the Frame Mounted system body is mounted on the separate
Chassis/Frame.
 And wheels are mounted on the Chassis not to the body.

11. Monocoque Body structure

12. Frame Mounted Body Structure

13. BIW Structure can be divided into following sub structures:-
› Under Body Structure
› Front End Structure
› Body Side Structure
› Closures
› Roof

14. All those substructures consists of the following major panels:-
 An Under Body Structure :-
Dash panel-provides partition b/w engine and the driver cabin.
FRT floor - provides base for seats.
Raiser - connects front floor to rear floor by providing level difference.
Rear floor - floor on the rear of the car and provides partition from ground
and base for rear seats
Rear wheel house
 Front End Structure :-
Plenum Panel- a chamber located b/w the throttle body and runners of the intake
manifold.
FRT wheel house(Fender)- is an encasement around the frt wheel.
Wing panel - outer most side panel in the front .
Cowl -portion of the body bounded by the front fenders, the base of
the windshield, and the rear edge of the hood.
Upper tie bar -upper panel in front connecting the two sides of front structure.
Lower tie bar- lower panel in front connecting the two sides of front structure.

15.  Body side Structure:-
A- pillar - front most support to the roof
B- pillar - second support to the roof
C/D pillar - c- is rear most support to roof in case of two row seating
system, it will be third one.
D- is the fourth support usually rear side of quarter panel.
Ring panel - a structure panel connecting the rear and front portion.
Quarter panel - rear most panel of a body side structure.
Drip rails / Gutters- an exposed channel applied to the roof over the side
windows to direct water away from the windows.
 Closures :-
All doors
Hoods/Bonnet -a hinged panel providing access to the engine
compartment.
 Roof Structure:-
Roof
Headers - structural member above the windshield at juncture
with the forward edge of the roof panel.
Bows

16. Reinforcement component
The part which are used to support and provides stiffness and strength to other
components of BIW.

17. Factors affecting design and construction of BIW:-