Week 1:- Introduction to BiW and Fixtures Challenge

Q.1 What is BIW & define its parts?

ANS.

First of all, BIW stand for Body In White and it is nothing but welded sheet metal components or parts of vehicles on which different automobile components like chassis, engine, etc. are mounted.

These welded structure is then painted with grey colour primer, hence known as Body In White due to its colour tone.

BIW parts are as follow:

i) Body sides: Body sides of BIW structure are nothing but side parts. It consist of Body Inner and Body Outer.

a) Body inner: Inner part of side body is known as Body Inner.

b) Body outer: Outer part of side body is known as Body Outer.

ii) Under body: Under parts of BIW structure are nothing but Under Body.

a) Engine compartment : Under part of front BIW structure is Engine Compartment.

b) Rear compartment: Under part of rear BIW structure is Rear Compartment.

c) Main floor: Under part of middle BIW structure is Main Floor.

iii) Closures: Closing parts of BIW structure are known as Closures.

a) Front door: These parts are used to close front BIW structure.

b) Rear door: These parts are used to close rear BIW structure.

c) Hood: These parts are used to close engine of BIW structure.

d) Tailgate (deck lid): These parts are used to close deck of BIW structure.

iv) Roof: Top closing part of BIW structure is Roof.

a) Roof inner: Inner part of roof is Roof Inner.

b) Roof outer: Outer part of roof is Roof Inner.

v) Fender: Part above wheels is known as Fender.

Q.2. What do you understand by BIW nomenclature?

ANS. BIW structure consist of number of components or parts and each parts have some name to identify such number of parts or components of BIW structure.

As there is small difference between US English and UK English, components or parts of BIW structure having differenrt nomenclature. Some of them are as below:

UK	US
Inner wing panel Suspension Tower Engine (longitudinal) rail Rear parcel tray Backlight frame Central (longitudinal) tunnel B-pillar C-pillar D-pillar	Motar compartment side panel Shock tower Motar compartment lower rail Package Shelf Rear header or backlite header Tunnel B-pillar C-pillar D-pillar

Q.3. What is fixture & its types?

ANS. As name suggest Fixture is nothing but assembly of different units used to fix or hold some components or parts for which the fixture is designed. This fixture is design with the help of 3-2-1 Principle, also known as Principle of Locations or 6- Pin or 6-Point Location Principle. These fixture is designed in such a way that holding component should not be vibrate or distort or under stress due to tight clamping or some difffent reasons.

Types of Fixture are as below:

i) Production Fixture:

As name suggest production fixture is used in mass production. As these fixtures are used in mass production, they should have high rigidity and simple in operational activities for opertor. Because these fixtures are used in mass production, they are maintained periodically or time to time. Loading and unloading should be easy in these fixtures.

ii) Pre-production Operation Fixture:

We can say these type of fixtures are prototype fixtures, because these fixtures are used for newly devloped parts or component. Later on these fixtures are modified or improved.

iii) Checking Fixture:

These fixtures are used for inspection purpose or checking purpose of parts ot components which are manufactured or processed under production fixtures and to check or inspect accuracy level and wheather the parts or components are manufactured without defects.

Q.4. What is the basic principle of fixture design?

ANS. Basically fixtures are used to hold or fix the components. To fix the component we have to restrict 12 degrees of freedom to keep part or component stable while processing. Fixtures are designed using 3-2-1 principle of locations. 12 degrees of freedom are:

1. + X direction
2. - X direction
3. + Y direction
4. - Y direction
5. + Z direction
6. - Z direction
7. Clockwise along X axis
8. Counter-clockwise along X axis
9. Clockwise along Y axis
10. Counter-clockwise along Y axis
11. Clockwise along Z axis
12. Counter-clockwise along Z axis

Q.5. Elaborate types of BIW Stations?

ANS. Elaboration of types of BIW Stations are as below:

1.Tool Station:

Different Tool stations are as below:

1. Geo Fixture: For accuracies Geo fixtures are used and pin tolerance of this fixture is -0.15.
2. Re-spot Fixture: Missing spots are processed in this fixture having pin tolerance of -0.28.
3. Marraige Fixture: Marraige Fixture are used to assemble inner panel and outer panel.
4. Framer Fixture: Component assemble in Marraige Fixture are now assemble with roof.
5. Checking Fixture: As name suggest this fixture are used to inspect processed component.

2. Gripper Station:

Gripper is used to hold device and move from one position to another. Also known as End Effector of Robot.

1. Material Handelling Gripper: As name suggest these gripper are used to handle or move components from one to another station.
2. Process Gripper: Along with holding component this gripper is also used for completing processing.
3. Combo Gripper: Thse is used for both holding and processing, hence known as Combo Gripper.
4. Dual Gripper: Used to hold two components or parts onboth side,hence known as Dual Gripper.

3. Stand Station:

1. Pedestal Stand: On this stand tools are mounted in such a manner that gripper can easily move along the tool mounted on stand for processing. Pedestal Stand permanently mounted on base of fixture.
2. Gluing or Sealer Stand: Gluing or Sealer Gun are mounted on this stand and this stand also permanently fixed on base of fixture.
3. Docking Stand: Due to limitation of pay load capacity of gripper of robot, these stand is used.
4. Date Stamp Stand: As name suggest Date Stamp Stand is to mention date of manufacturing or fixture numbers.

4. Miscellaneous Station:

1. Curing: These stand is used provide curing time to the components or parts.
2. Conveyor: Conveyors are used in material handling proessing.
3. Take out Trolley: take out Trolley are used to take out components or parts in assembly line for insoection purpose.
4. Buffer Stand: These stand is used to store components.

Q.6. What are the basic terminologies used in the BIW fixture?

ANS. Basic terminologies used in the BIW fixture are:

1. Mylars or NC or Fingers: Mylars are the parts which are in direct contact with component in fixture from both top and bottom side. Top side mylars are called Clamping Mylars where as bottom side mylars are known as Resing Mylars.
2. PLP (Principle Locating Points): These points help us to locate component with accurate geometry of the assembly.
3. Risers: These are used to give required height to the units in fixtures.There are several types of risers like L-type, T-type, etc.
4. Blades: Blades are mounted on risers.
5. Shim: Shims are used to adjust or achive dimensional stability. Shims are basically plates having smaller thickness (3mm or 5mm).
6. Rough Locators: Rough Locators are used to hold component in correct manner and also to support or rest the component.
7. Hardwares: These consist of nuts, bolts, etc.
8. Co-ordinate Measuring Machine (CMM): These machine are used measure geometry of components or parts using probe.
9. Number Plate: Number Plate having numbers on each and every plate which helps to identify the correct parts while assembly of fixture.
10. Namee plate: Name plate are used to mention name of parts.
11. Clamp Arm: Clamp Arm are used in clamping the component securely which are pivoted at one side along which it rotate.
12. Pivot: It is a axis along which arm rotates.
13. Class A Surface/ Skin Surface: Outer visible surface of components known as Class A Surface or Skin Surface.
14. Sensors: They are used to sense and send some inputs to electronic or mechanical devices which helps the operator who work on the fixture.
15. Reed Switches: These electronic switches mostly used to operate cylinders in fixtures. Reed switches operate using sensors.