Design of backdoor

AIM:

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

INTRODUCTION:

A tailgate, also known as a car back door, is the hinged door or gate at the rear of a vehicle that allows access to the cargo or luggage compartment. It is a critical component of pickup trucks, SUVs, and other larger vehicles designed for hauling cargo or towing trailers.

The tailgate is usually made of sturdy materials such as steel, aluminum, or composite materials to withstand the weight and stress of heavy cargo loads. It can be opened by using a handle or lever on the exterior of the vehicle or by using a remote key fob or an interior release mechanism.

Tailgates can have various configurations depending on the specific make and model of the vehicle. Some tailgates are a single piece that opens downward, while others may have a split design with two doors that open horizontally to either side. Some tailgates may also have a built-in step or ladder for easier access to the cargo area.

In addition to providing access to the cargo area, tailgates also serve as a safety feature by preventing cargo from falling out of the vehicle while in motion. They also help to improve aerodynamics, reducing wind drag and improving fuel efficiency.

Tailgates can also be customized for different purposes, such as for use as a work surface or seating area during outdoor events or as a display area for advertising or promotional materials. Overall, the tailgate is an essential component of many vehicles and plays a crucial role in both functionality and safety.

Back Door Assembly:

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

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

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so by using of aluminium we can reduce the number of parts and assembly involvement. and it is castly material.

these are the certain tests are done in back door,not only back door all components must pass these tests but different components have different test because of the functionaly.

Different types of Sheetmetal operations are done in 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.

Roller hemming is a metal forming process used to create a hem, or a folded edge, along the edge of a metal panel. It is commonly used in the automotive industry to create a smooth, finished edge on vehicle body panels, such as doors, hoods, and fenders.

The process involves using a series of rollers to gradually bend and fold the edge of the metal panel over onto itself. The rollers are typically made of hardened steel and are carefully calibrated to produce a consistent hem with minimal distortion or wrinkling.

Roller hemming can be performed manually using a hand-held tool or by using automated machinery. In the automated process, the metal panel is placed on a bed that moves through a series of rollers, with each roller applying a specific amount of pressure to achieve the desired hem shape.

Roller hemming offers several advantages over other methods of forming a hem, such as bending or folding. It produces a smoother, more uniform edge with a consistent thickness and provides excellent edge protection against corrosion and other types of damage. It is also a more cost-effective and efficient method, as it requires minimal setup time and can be performed at high speeds.

There are various types of hemming operations:

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

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

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

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.

Blanking:

Blanking is a cutting operation of a flat metal sheet and the article punched out is known as blank. Blank is the required product of the operation and the metal left behind is considered as a waste.

Punching:

It is similar to blanking only the main difference is that, the hole is the required product and the material punched out from the hole is considered as a waste.

DESIGN PROCESS:

Class A Surface:

To check the give class A surface has any gap or surface has to be repaired according to the smoothness.Then create it into two surface upper and lower panel.

Door outer panel upper Door outer panel lower

TOOLING AXIS :

Create the tooling axis ,using bisecting line at required axis .

Door inner pannel can be create by following proces like stealing flange, connecting flange and joing together for creating inner pannel.

Then for the windshield panel mounting, windshield panel is created and joined with sealing flange.

A mastic sealent is used on the surface to connect the inner and outer panel with a gap of 5mm.

CREATING REINFORCEMENTS:

The reinforcements can be directly offseted from the inner panel surface using the Wave geometry linker and trim it accordingly. The give ticken at 1.5mm.

All reinforcements are shown below:

Hinge Reinforcement:

Gas Stay Reinforcement:

Wiper Motor Reinforcement:

Latch Reinforcement:

Hemming:

Hemming is an important process in the automotive industry that plays a crucial role in the production of high-quality, finished car body panels that meet the strict safety and performance standards of modern vehicles.

Draft Analysis:

Draft analysis is an important part of the product design process because it can help to identify potential issues early on and prevent costly mistakes during production. By ensuring that the product is designed in a way that can be easily manufactured using injection molding or other processes, the final product will be of higher quality and will be produced more efficiently and cost-effectively.

Assembly: