Lecture Notes on BIW Fundamentals

Jul 28, 2024

Lecture Notes on BIW Fundamentals

Introduction

  • Session focused on BIW (Body in White) fundamentals in the automotive industry.
  • Encouraged an interactive format to gauge understanding among participants.

Participants' Background

  • Majority of participants are college students from various years in Mechanical or Automotive Engineering.
  • Some participants are working in the industry or searching for jobs.

Understanding BIW

  • Definition of BIW: The stage in automotive manufacturing where the car body frame is assembled before painting and component installation.
    • Made primarily of sheet metal components, typically steel or aluminum in high-end cars.
    • CED Process: Cathodic Electronic Deposition process used for painting the chassis.

Outline of the Session

  1. Introduction to BIW
  2. Classification of BIW components
  3. BIW subsystems
  4. Key components of BIW
  5. Assembly process
  6. Types of joining processes
  7. Total overview and credits

BIW Components Classification

  1. Underbody:

    • Comprises the chassis and mounting areas for seats and tanks.
    • Divided into engine room, cabin floor, and rear floor.

  2. Upper Body:

    • Includes A, B, C, and D pillars, roof structure, and body side outer.
    • Body side outer is the biggest component affecting crash safety.

  3. Closers:

    • Components that can open and close, such as doors and hood.
    • Fender is bolted instead of welded due to its non-load bearing purpose.

BIW Subsystems

  • Emphasis on underbody, upper body, and closures.
  • Discussed the role of the upper body in vehicle strength, stability, and crash safety.

Key Components in the Upper Body

  • Pillars: A, B, C, D pillars provide structural strength.
  • Torsional Stiffness: Important for vehicle dynamics and stability, especially during turns.
  • Understanding the design strategy behind different grades of steel and their placement based on crash regulations.

Assembly Process Overview

  1. Stamping: Sheet metal is shaped using punch and dies.
  2. Body Assembly: Components are welded and assembled to create the BIW.
  3. Paint Process: Following assembly, the car body is painted.
  4. Trim & Chassis: Installation of seating and other components.
  5. Inspection: Quality control checks ensure defects are addressed before shipping.

Joining Processes and Techniques

  • Robotic and manual welding processes are used across various components.
  • Hemming and adhesive bonding mentioned for non-visible areas to maintain aesthetics and reduce weight.

Conclusion

  • Session informs on essential aspects of vehicle design and assembly.
  • Following sessions will delve into more detailed processes and regulations governing automotive design.