Week 9 - Project 1 - Door Trim Lower with Engineering Features

Aim:

To Create the Door trim lower component through the given Class-A surface.

Objective:

The main aim of this challenge is to create a solid body of 'Door Trim Lower' with the help of the closed surface method by using the 'Generative shape design' workbench in CATIA V5. Performing the 'Draft Analysis' on the solid part body of the Door trim.

ABOUT DOOR TRIM LOWER

• An interior component attached to the inner side of the door.
• This product does more than merely improve the appearance of the vehicle interior.
• Rather, it is a vital module component that creates a more comfortable interior by providing a variety of accouterments and functions.

MATERIAL USED FOR DOOR TRIM LOWER

ABS(Acrylonitrile butadiene styrene)

WHY ABS(Acrylonitrile butadiene styrene)

• COST EFFECTIVE
• LOW MELTING POINT
• HIGH IMPACT STRENGTH

COMPAEISION OF MATERIAL TO CHOOSE FOR DOOR TRIM LOWER

Attributes	ABS	NYLON
Impact strength	High	low
Cost	Low	High
Melting point	low	High
Plastic Type	Thermoplastic	Thermoplastic

Properties	ABS	Nylon
Melting point	190 -270	268.8oC
Density	1.05 g/cm3	1.31 g/cm3
Molecular weight	211.3 g/mol	224.3 g/mol
Ultimate tensile strength	35MPa	85MPa
Elongation at break	30%	90%

MECHANICAL PROPERTIES OF ABS(Acrylonitrile butadiene styrene)

• Key Properties of ABS
  • High rigidity.
  • Good impact resistance, even at low temperatures.
  • Good insulating properties.
  • Good weldability.
  • Good abrasion and strain resistance.
  • High dimensional stability (Mechanically strong and stable over time)
  • High surface brightness and excellent surface aspect.

MANUFACTURING MACHING FOR DOOR TRIM LOWERR

INJECTION MOLDING MACHINE

TOOLING AXIS

• The direction in which the mold or core and cavity opens is the tooling axis.

CLASS A SURFACE

• Class-A (or 'Strak') is a term used in specifically in automotive design.
• It describes the final production surface data for the aesthetic parts of the car.
• The term 'Class A' is often misunderstood, but it's generally seen as the 'Holy Grail' of surface modeling.
• Class A surface is used to show to the customer visulization,and it is a aesthetic syurface.

CLASS B SURFACE

• The Class B finish is a quality finish with only minimal imperfections.
• A Class B finish is the most common finish for exterior surfaces.
• It is normally specified on surfaces such as external covers, panels, and parts that are fairly prominent.
• It is a offset surface of A,Which the surface were can not able to see Over the customer.

CLASS C SURFACE

• The Class C finish allows more imperfections than Class A or B.
• Class C is often specified for interior surfaces not readily visible, surfaces that will be covered by another part when assembled, or surfaces which the Customer feels do not need to meet a high cosmetic finish.

DRAFT ANALYSIS

• The draft analysis technique is used to analyze whether our part model created in CAD is manufacturable based on the draft condition applied.
• Here the part should get easily removed from the panel dies .

DRAFT ANALYSIS OF DOOR TRIM CLASS A

DRAFT ANALYSIS OF COIN HOLDER FINAL COMPONENT

SCREEEN SHOT OF SOLID BODY WITH PROPER COLOUR COATED OF CLASSES A,B&C

ENGINNERING FEATURES

MATERIAL SELECTION FOR ENGINEERING FEATURES

POLYPROPYLENE

WHY POLYPROPYLENE

• which toughness,
• flexibility,
• light weight, and
• heat resistance .

DOG HOUSE

• Dog house is an engineering feature used in plastic trim design.
• Dog houses are used as supporting feature.
• Sometimes other engineering features like snaps; locators etc.
• are mounded on them to increase their strength.

SKETCH FOR DOG HOUSE

DRAFT ANALYSIS OF DOG HOUSE (EXTERNAL)

DRAFT ANALYSIS OF DOG HOUSE (INTERNAL)

HEAT STAKES

• Heat staking also known as thermoplastic staking is the process of joining two dissimilar materials together.
• In heat staking we use local heating and cooling to raise the temperature of plastic components and allow plastic reforming to be carried out.

SKETCHES FOR HEAT STAKES

DRAFT ANALYSIS OF HEAT STAKES

3-2-1 PRINCIPLE:

• A work-piece free in space can move in an infinite number of directions.
• For analysis, this motion can be broken down into 12 directional movements or "degrees of freedom".
• All 12 degrees of freedom must be restricted to ensure proper referencing of a work-piece.
• Notice the 6 axial degrees and 6 radial degrees of freedom.
• The axial degrees of freedom permit straight-line movement in both directions along the 3-principle axis shown as X, Y & Z.
• The radial degrees of freedom permit rotational movement, in both clockwise & counter clockwise radial directions around the same three axes.

LOCATORS

• The device to establish and maintain the position of the workpiece in work holders such as jig and fixture to ensure repeatability of work holder.
• The locating device for a work holding device mainly depends on the property of workpiece and the overall machining process.

4-WAY LOCATORS:

• 4-way mean you prevent movement at 2 axes (+X, -X, +Y and -Y) on the plane. Generally,
• you have cylindrical pin on the fixture and circular hole at workpiece part.

DRAFT ANALYSI OF FOUR WAY LOCATORS

DRAFT ANALYSIS OF FINAL DOOR TRIM PANNEL WITH ENGINEERING FEATURES

Conclusion:
1. The Door trim is created using a generative shape design, Part workbenches.
2. The model is designed with the nominal draft angle of 3 degrees for the component and
0.5 degrees for the Attachment features.
3. The Closed body of the model is created using close body command in part design
workbench.
4. The attachment features in the model are designed following the design rules.
5. The tree structure is maintained clearly.