Week 8:- 3D Finishing - Challenges 1

1. 3D finish process is the a process in which finishing of fixture is done means making fixture ready for final 2D detailing and simulation.

Steps followed while doing 3D finish:

• Holes concentricity and hole sizes should be ensure
• Gaps or clearance is maintain between different units to ensure proper working
• Fastener are used and color are applied according to customer standard.
• Standard colors are used for easy understanding like yellow for tapping and blue for dowel hooles.
• Renaming of every part is done
• After all this steps fixture is sent to simulation and final 2D detailing.

2. The points need to be taken care of while finishing the design.

1. Hole concentricity & Hole sizes
2. Mchining area
3. Normality
4. Holes clouring standard
5. Pneumatic lay-outing
6. Gaps checking
7. Fasteners implementaion
8. Avoiding clash between different parts
9. Mylars Splitting as per panel profile
10. Poper renaming of parts/assemblies as per the standard.

3.Rough locators are used to locate car panel and also guide the operator to load the car panel in the fixture perfectly. Standard Rough locators are also available.

Uses:

1. It is used to locate the car panel in the fixture.
2. It is also known as Pokayoke or Fool Proofing as part is located in fixture accurately
3. Accuracy is maintained due to use of rough locators.

4. The points you need to consider while designing a rough locator.

• Height of rough locators should not be more than the permissible ergo height of the fixture.
• The entry poit/ top point of the rough locator must be 10mm-15mm above the panel surface.
• Rough locators should habe adjustment in the direction of guiding plane.
• 2mm gap to be maintained between rough locator and panel at the time of design and we can provide adjustment of 5-10mm in the positive or negative direction of guide plane.
• Rough locators can be rod type or flat type, depending upon the standards and other conditions.

5. Gun study is the process of checking whether the gun is able to weld the selected car panels. The below images shows the weld gun dong spot welding and the weld location where the spot is created on the car panel. Gun study is necessary as the BIW car panels are complex in share and sixe. In 3D software gun study is done by actually introducing welding gun in fixture that we have designed. According to that units are designed so that there's no problem while welding process.

6.The points need to consider during the gun study :

1. The axis of weld spot along weld direction must be normal to the weld surface
2. Total no. of weld spot and time required for each is calculated for knowning total time required for welding that car panel.
3. Robot cycle time is calculated while doing proper gun study.
4. Collision checking is done on simulation software to check whether the welding process is done without ant collision with any units in fixture.

7. Pneumatic Routing a planning tube lines route properly, leak proof and efficient working of pneumatic devices used in a fixture like cylinders, solenoid etc.

8. Solenoid valves are used to actuate the air flow in cylinders as per the sequence through manual or PLC operated system. It is a mechanical device use to control or regulate the flow of fluid.

components of solenoid valve are as shown in below.

9. Valve banks are basically a system in which n numbers of solenoid vlaves are mounted, in order to maintain one common inlet and outlet of air to all the valves.

Valve banks are mostly mounted on the fixture sides or on the base plate depending upon the various conditions.

10. A sensor is a device that produces an output signal for the purpose of sensing of a physical phenomenon. In the broadest definition, a sensor is a device, module, machine, or subsystem that detects events or changes in its environment and sends the information to other electronics, frequently a computer processor.

Application:

1. To check the pressence of car panel
2. To detect the position of sliding unit
3. When there is no. of similar car panels weld on same fixture sensor are used to detect car panel place in fixture.

11. Type of sensor:-

The Mass Air Flow Sensor	Calculates the density and the volume of the air taken in by the engine
2	The Engine Speed Sensor	Monitors the spinning speed of the crankshaft
3	Oxygen Sensor	Measures the amount of unburden oxygen presented in the exhaust pipe
4	Manifold Absolute Pressure Sensor	Measures the manifold pressure inside and outside
5	Spark Knock Sensor	Ensures that the fuel is burned correctly
6	Fuel Temperature Sensor	Ensures the right amount of fuel is injected to keep the motion smoothly
7	Voltage Sensor	Manages the car speed and ensures the speed is controllable

12. The fundamental points that need to consider while designing or selection of sensor.

1. Response speed
2. Sensing range
3. Repetition accuracy
4. Electrical connection
5. Mounting type
6. Sensor provide safety to operator
7. Output from sensor are given to PLC as an input signal.
8. Electrical sensor are used to detect car panel in fixture.