Week 2:- BiW Fixture Basics Challenge

1)Project execution activity starts after receiving RFQ.after discussing the specification offer is submitted like what is the duration of the project and how much time required for the project etc.then the customer issues a PO if it suits its requirements.then the timeline is preparedafter which we have to provide BOM which we are going to use in the project like the type of cylinders and sensors etc,then comes the design stage which takes most of the time and is prepared until customers approval.after the freeezing of design detailing is done and drawings are released for manufacturing and BOP are released. then the assembly is done which awaits quality inspection.after which it goes in internal trail & testing.after online trail it is packaged and dispatched and installation is a carried as per layout. trails and training are done at customer.additional measures are implemented if suggested.buyoff meeting is carried out and then the tool is finally delivered.

2)there are several joining process,but the commonly used joining processes which are used in BIW are:-

a)resistance welding is made by conducting a strong current through the metal combination to heat up & finally melt at localised points.a force is applied before during &after the application of current to confine the contact area.

b)arc welding is the most common method used throughout the industry.in this consumable or non-consumable electrodes are used for joining of metal components.

c)mechanical fastening are the simpler form of joining.these may or may not be permanent joints e.g in case of screw &bolts we can dismantle the joined parts .in case of riveting the joints are permanent and hence not recommended for reuse.they are widely used in electric cars nowadays because of the use of alloys used for lightweight purposes.

d)adhesives & glueing is another method used in industry ,these provide a chemical advantages as well as heat resistance to the car panels

3)resistance welding is made by conducting a strong current through the metal combination to heat up & finally melt at localised points.a force is applied before during &after the application of current to confine the contact area.types:-

• resistance spot welding-mostly used because of short weld time& hence high weld speed
• resistance seam welding-used where we need continous welding as in case of container,fuel tank,heat exchanger etc
• resistance projection welding-used to weld studs,nuts on sheet metal components
• arc welding-most commonly used welding & has high adaptability to automation & robotic techniques

Resistance welding is used because of strength & durability of automobile .

4)Fusion welding is a process that uses heat to join or fuse two or more materials by heating them to melting point. The process may or may not require the use a filler material.

These process include:

Shielded Metal Arc Welding (SMAW), also known as manual metal arc welding (MMA or MMAW), flux shielded arc welding or stick welding. Suitable for welding ferrous and non-ferrous materials in all positions.

Metal inert gas welding, also known as Gas Metal Arc Welding (GMAW). MIG and MAG welding are the most common arc welding processes, in which an electric arc forms between a consumable wire electrode and the workpiece leading them to melt and join. Both use a shielding gas to protect the weld from airborne contaminants, or oxidation in the case of MIG welding.

Tungsten inert gas welding, also known as Gas Tungsten Arc Welding (GTAW). This arc process uses a non-consumable tungsten electrode to create the arc between the electrode and the base plate. An inert shielding gas is used to protect from oxidation or other atmospheric contamination. This process can be used autogenously on thin parts, but will require the addition of a wire, rod, or consumable to be added for thicker parts.

Plasma arc welding. This process uses an electric arc created between an electrode and the torch nozzle. The electric arc ionises the gas (usually argon) in the chamber creating what is called a 'plasma.' It is then forced through a fine bore copper nozzle that constricts the arc and directs it to the workpiece, allowing the plasma arc to be separated from the shielding gas (which is usually made from a mixture of argon and hydrogen).

5)3-2-1 is the best and cost effective method of part location.there are total 12 degrees of freedom i.e 6 rotational and 6 translational degrees of freedom.with the help of this principle we restricts these 12 degrees of freedom.in this method a part is located such a way that minimum part is used and there is no degree of freedom left.3 locators blocks are placed to restrict the movement in +z,-z direction along with rotational motion in clockwise & anti clockwise x & y . 1 pin in used to restrict the translation motion in +x,-x & +y,-y . the final rotational motion is restricted by adding another pin.

6)BCS has been widely used in the automotive industry for drawing of body parts,products.a coordinate system is a reference system consisting of a set of points, lines & surfaces used to define the position of point in space in either 2d or 3d.

x is longitudinal direction-we go negative to positive from front end of car to rear end

y is transverse direction -we go negative to positive from left end of car to right end of the car

z is vertical direction - we go negative to positive from ground to roof of the car

7)body planes are 3 mutually perpendicular imaginary planes.these are generally considered to be present at the driver position or at the engine location of the car depending upon the customer.the 3 lines are front o line,centre o line & bottom o line

body line dimensions are essential for the reasons:-

• it defines the exact location or position of each product in the vehicle with respect to a fixed origin
• it ensures a flawless design for assembly
• while designing lines, all the designs are carried out relative to bodyline,fixture,turn tables
• it aims at creating a standardised system
• it assists in quality checks