Vehicle body repair
Body Engineering for Production
Download 12.05 Mb.
|
- Navigate this page:
- 1.12 Methods of Construction
- Composite Construction (conventional separate chassis)
- Figure 23
1.11 Body Engineering for ProductionThe body engineering responsibilities are to simulate the styling model and overall requirements laid down by the management in terms of drawing and specifications. The engineering structures designed for production, at a given date, at the lowest possible tooling cost and to a high standard of quality and reliability. As competition between the major car manufacturers increases, so does the need for light and more effective body structures. Until recently the choice of section, size and metal gauges was based upon previous experience. However methods have now been evolved which allow engineers to solve problems with complicated geometry on a graphical display computer which can be constructed to resemble a body shape. The stiffness and stress can then be computed from its geometry and calculation made of the load bearing of the structures using finite-element methods. With the final specifications approved, the new car is ready for production. At this stage an initial batch of cars is built (a pilot run) to ensure that the plant facilities and the workforce are ready for the start of full production. When the production line begins to turn out the brand new model every stage of production is carefully scrutinized to ensure quality in all vehicles to be built. 1.12 Methods of Construction The steel body can be divided into two main types: those which are mounted on a separate chassis frame and those in which the underframe or floor forms an integral part of the body. The construction of today’s mass-produced motor car has changed almost completely from the composite, that is a conventional separate chassis and body, to the integral or mono unit. This change is the result of the need to reduce body weight and cost per unit of the total vehicle. Composite Construction (conventional separate chassis) The chassis and body are built as two separate units. The body is then assembled on to the chassis with mounting brackets, which have rubber-bushed bolts to hold the body to the rigid chassis. These flexible mountings allow the body to move slightly when the car is in motion. This means that the car can be dismantled into the two units of the body and chassis. The chassis assembly is built up of engine, wheels, springs and transmission. On to this assembly is added the body, which has been preassembled in units to form a complete body shell. 
Figure 23: Composite Construction (conventional separate chassis) Integral (mono or unity) Construction Integral body construction employs the same principles of design that have been used for years in the aircraft industry. The main aim is to strengthen without unnecessary weight and the construction does not employ a conventional separate chassis frame for attachment of suspension, engine and other chassis and transmission components. The major difference between composite and integral construction is hence design and construction of the floor. In integral bodies the floor pan area is generally called the underbody. The underbody is mad up of formed rails and numerous reinforcements. In most integral under-bodies a suspension member is incorporated in both the front and rear of the body. F  igure 24: Composite Construction Showing a Lutus Elan Chassis before fitting the Body
Figure 25: Complete Body Assembly of Austin Maestro 
Directory: Content -> APPRENTICE -> liu Content -> Resolution Content -> American bar association adopted by the house of delegates Content -> Additional File 26 Content -> Guide to completing the collection using the Omnibus system Content -> Management and Marketing Content -> Sigaccess annual Report Content -> Study Guide For Students Only Dress Rehearsal January 29, 2014 7: 00 pm jubilee Auditorium Content -> Benjamin Franklin: In Search of a Better World Section One Content -> Extended range forecast of atlantic seasonal hurricane activity and landfall strike probability for 2013 liu -> Trade of heavy vehicle mechanic Download 12.05 Mb. Share with your friends:
|