INTRODUCTION
PRELIMINAR STUDIES AND CONSIDERATIONS
MAINTENANCE AND DAMAGE PREVENTION
WORK ON BASIC VEHICLE
MOUNTING AND CONSTRUCTION
POWER TAKE-OFF
ELECTRIC AND ELECTRONIC SYSTEMS
APPENDIX
150
Body Builder Manual Part II, Specific Book LCV
V1.0, February 2015
Fig. 5-104 SPBGC52_003 closed section beam
5.2.4
Subframe design requirements
The chassis frame, subframe and reinforcement interact to absorb all kinds of ten
-
sions that can arise during use of the vehicle.
The design and size of the subframe, fixing type and reinforcement are determined
by a number of factors such as chassis type, torsional stiffness class and type of
service.
Forces on the subframe
Depending on the type and use of the superstructure, it is necessary to design sub
-
frames that have different stiffness and behaviour to withstand torsion and flexion
forces. For example, flexible subframes are used for platform or tipper bodies, and
rigid or very rigid subframes in refrigerated bodies or tank bodies.
Also, the subframes should be designed to absorb lateral forces produced when the
vehicle turns, or forces produced on the rear overhang due to the trailer.
Subframe design
The following guidelines should be considered for all types of subframe:
- The subframe must be continuous without cuts throughout the chassis frame.
- It must be flat and lie on the upper flanges of the chassis frame longitudinal
members.
- The subframe structure should be symmetrical and spread the load evenly on
both sides of the chassis frame.
- The different elements that form the subframe must not interfere with or limit
the movement of any moving parts of the vehicle.
- The subframe should stay as close as possible to the front of the vehicle, in
order to reduce vibration, which would impair comfort while driving.