Roof challenge

OBJECTIVE

To design and develope automotive roof with its components and do draft analysis to check for manufacturability of the part and with the feedback change the model design when needed.

ROOF DESIGN

1. Front Roof Rail

2. Rear Roof Rail

3. Bow Roof Rails

4. Center Roof Rail

a) Heat distortion criteria

Heat distortion is the temperature at which the metal softens and deforms under specific load. This calculation is done to check the maximum temperature the roof can withstand.

W = (1.73 x x L ) + (1.85 x x ) + 1.10 x x l ) -2.68

where,

L – Roof length in X-9direction

t – Roof plate thickness

l – Bow Roof Span

Rx- Lateral direction curvature radius of roof panel Y cross-section on roof bow

Ry - Longitudinal direction curvature radius of the roof panel X cross section on roof bow

From the above table 'w' values are in accordance with the judgement range i.e w value should be below 2.75 for bow roof distance prediction.

b) Snow load prediction

Snow load prediction is done to check if the roof will be able to withstand the snow load during snow fall.

c) Draft analyis

The draft analysis was done to detect if the drafted part will be easily removed. A draft angle of 5 degree was used for the analysis and the model was found to have a postive draft.

RESULT

A front, rear and bow roofs along with necessary reinforcements and flanges are designed in accordance with heat distortion criteria and snow load prediction formulas.