Week 8:- 3D Finishing - Challenges 1
- What do you understand about the 3D finish process?
3D finish process is the process in which finishing of a fixture is done means making the fixture ready for final 2D detailing and simulation.
- Steps followed while doing 3D finish:
- Holes concentricity and hole sizes should be ensured.
- Gaps or clearance is maintained between different units to ensure proper working
- Fasteners are used and colours are applied according to customer standards.
- Standards colours are used for easy understanding like yellow for tapping and blue for dowel holes.
- Renaming of every part is done
- After all these steps the fixture is sent to simulation and final 2D detailing.
2) The points need to be taken care of while finishing the design are:
- Hole concentricity and hole sizes
- Machining area
- Normality
- Holes colouring standard
- Pneumatic lay-outing
- Gaps checking
- Fasteners implementation
- Avoiding clash between different parts
- Mylars splitting as per panel profile
- Proper renaming of parts/ assemblies as per the standard.
3) What are rough locators and what is their use?
Rough locators are to locate the car panel and also guide the operator to load the car panel in the fixture perfectly. Standard rough locators are also available.
Uses:
- It is used to locate the car panel in the fixture.
- It is also known as Poka-yoke or fool proofing as the part is located in the fixture accurately
- Accuracy is maintained due to the use of rough locators.
4) What are the points you need to consider while designing a rough locator?
The points you need to consider while designing a rough locator:
- The height of rough locators should not be more than the permissible ergo height of the fixture.
- The entry point/top point of the rough locator must be 10-15mm above the panel surface.
- Rough locators should have adjustments in the direction of the guiding plane
- 2mm gap to be maintained of design and we can provide adjustment of 5-10mm in the positive or negative direction of the guide plane.
- Rough locators can be rod type or flat type depending upon the standards and other conditions.
5) What is the gun study process?
Gun study is the process of checking whether the gun is able to weld the selected car panels. The below images show the weld gun doing spot welding and the weld location where the spot is created on the car panel. Gun study is necessary as BIW car panels are complex in shape and size.In 3D software, the gun study is done by actually introducing a welding gun in the fixture that we have designed. According to that units are designed so that there is no problem while the welding process.
6) What are the points needed to consider during the gun study?
- The axis of the weld spot along the weld direction must be normal to the weld surface.
- Total no.of weld spots and time required for each is calculated for knowing the total time required for welding that car panel.
- Robot cycle time is calculated while doing the proper gun study.
- Collision checking is done on simulation software to check whether the welding process is done without any collision with any units in the fixture.
7) What is Pneumatic routing?
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) What is the solenoid valve?
Solenoid valves are used to actuate the air flow in the cylinders as per the sequence through a manual or PLC-operated system.It is a mechanical device used to control or regulate the flow of fluid.
Components of the solenoid valve are as shown below
9) What is Valve bank?
Valve banks are basically a system in which n numbers of solenoid valves 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) What is a sensor?
A sensor is a device that produces an output signal for the purpose of sensing 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.
Applications:
- To check the presence of the car panel.
- To detect the position of the sliding unit.
- When there are no.of similar car panels weld on the same fixture sensor are used to detect car panel place in fixture.
11) Types of sensors:
The following is a list of different types of sensors that are commonly used in various applications. All these sensors are used for measuring one of the physical properties like Temperature, resistance capacitance , conduction, heat transfer etc.
- Temperature sensor
- Proximity sensor
- Accelerometer
- IR sensorI infrared sensor)
- Pressure sensor
- Light sensor
- Ultrasonic sensor
- Smoke sensor, gas and alcohol sensor
- Touch sensor
- Colour sensor
- Humidity sensor
- Tilt sensor
- Flow and level sensor
12) What are the fundamental points that need to be considered while designing or selecting the sensor?
A sensor unit is a unit designed to sense the car panel by using electrical sensors.
- The sensor unit is a unit designed to sense the car panel by using electrical sensors
- The signal from the sensors will be fed to the PLC and the next process will be executed.
- Sensors are used to confirm there is panel or component is present or not.
- It helps to avoid human error.
- Basically, sensors should be equal numbers as cameras to the number of panels in an assembly.
- Sensors should be designed in such a way that they can be adjusted in 3 directions.
- Sensors are also used for safety purposes of the operator.
- Typically proximity , laser, photoelectric sensors are used in fixtures
- Some major sensor manufactures are IFM, PEpperi-Fuchs, SICK, OMRON etc.