Challenge

Design of backdoor

HHarshit Bhavikatti14 Nov 2022

AIM OF THE PROJECT :

To design the back door of the carr and make the inner panel for the back door and also design the necessary

re-enforcements.

SOFTWARE : NX 12.0

Car Back Door and Components :

The back door is a hinged door/tailgate at the rear of the vehicle. It may be used for loading and unloading cargo, or to get passengers in and out, in case there are seats present at the rear. The back door comprises of certain components which form the back door assembly together.

What is back door of a car ?

A door which is located at the rear side of a car which gives access for the boot space to store luggage, spare wheel etc.

These doors can be operated manually or electric powered. In most of the luxury cars door is electrically operated.

TYPES OF BACK DOORS BASED ON THE WORKING POSITIONS ,

Top Mounted Door

2. Side mounted Door

3. Bottom Door

POWERED TAIL GATES :

GAS STAY MOUNTED TAIL GATES :

BACK DOOR ASSEMBLY INCLUDES :

Inner panel
outer panel
hinge and its reinforcement
wiper motor reinforcement
latch & stricker and its reinforcement
gas stay reinforcement

MATERIAL SELECTION FOR THE MANUFACTURING :-

the major problem in back door is material selection. mostly in past days steel is used, but it makes a very problems the steel parts have heavy weight,so it reduces the fuel economy, insted of steel presently in high end cars aluminium is used, the main objective of aluminium it have less desnser material and its sutaible for complex shapes, and it also gives the thcikness locally because it it done cating, in case of steel we used deep drawing operation. there are some of the advatanges and disadvantages are there

Different Sheetmetal processes used for manufacturing the Back Door

Deep Drawing:

The metal deep drawing process is an effective method of manufacturing of cups, cans and other similar deep drawing products. The deep drawings having two main categories.

1. First- stage drawing:

The blank shape of metal is placed on the die and contact with the punch. When the metal specimen is flat piece of sheet metal used in forming and finish the product. Initially the punch moves in downward direction. The outer rim of blank is subjected to pure radial drawing (drawing toward in vertical axes) between die and blank metal. The metal become a bend and sliding over die and also stretched between die and punch. The metal in vicinity of punch head and contact with it bend and slide over radii and stretch over punch head.

2.Redrawing:

The components drawn from first stage again it is redrawn convert into more depth to form a cup shape in the die and punch. The second stage of drawing is called as redrawing.

Embossing:

Embossing is a metal forming process for producing raised or sunken designs or relief in sheet materials by means of matched male and female roller dies, theoretically with no change in metal thickness or by-passing sheet or a strip of metal between rolls of the desired pattern. Metal sheet is drawn through the male and female roller dies producing a pattern or design on the metal sheet. Depending on the roller dies used, different patterns can be produced on the metal sheet.

Materials commonly used in the metal embossing process include:

Aluminum alloys
Steel alloys
Zinc
Copper
Galvanized steel
Brass
Cold rolled steel

Hemming:

Hemming is a forming operation in which the edges of the sheet are folded or folded over another part in order to achieve a tight fit. Normally hemming operations are used to connect parts together, to improve the appearance of a part and to reinforce part edges.

In car part production, hemming is used in assembly as a secondary operation after deep drawing, trimming and flanging operations to join two sheet metal parts (outer and inner) together. Typical parts for this type of assembly are hoods, doors, trunk lids and fenders.

There are various types of hemming operations:

Conventional die hemming: In conventional die hemming, the flange is folded over the entire length with a hemming tool.
Roll hemming: In roll hemming, the hemming roller is guided by an industrial robot to form the flange.

3. Open Hem: A Hem has a full round feature and a return flange. In open hem bend angle is equal to 180 degrees.

4. Tear drop Hem: In tear drop hem the bend angle is greater than 180 degrees.

5. Closed Hem: Hems without any inside radius are called as closed hem. Closed hems are not recommended if the hem geometry is to be painted or if the material used is SST or Aluminium.

Inputs for designing of backdoor:

Outer Panel - 0.75 mm
Inner Panel - 0.75 mm
Reinforcements - 1.5 mm

Class A surface:

backdoor outer upper and lower class a surface has to be repaired according to the smoothness. After repairing the surfaces, the door is divided into two parts as Door Outer Upper and Doo Lower Panel.