Week 8:- 3D Finishing Challenge 2

AIM:

Perform 3D finish for all units of Assembly design.

Create Rough locators for Assembly.

3D-FINISHING:

3d Finish is a process where the design is being finished and ready for final simulation and 2d detailing.

While finishing the design the nominality is checked which ensures the easy assembly of all the units.

The hole concentricity and hole sizes are checked which ensures the assembly of different parts.

The gaps between the different units are checked to ensure the proper individual working of different units.

Design the rough locators, which help to load a panel in correction orientation.

Design the pneumatic layout for pneumatic connection.

The gun study is a major and most important part of 3d finishing.

Selection of sensors and solenoid valves as per the requirement and implementation in design.

Fasteners are implemented as per the hole size and the standard color codes as per the customer requirement are applied to differentiate the type of hole whether it is a dowel hole, Threaded hole, or clearance hole.

Renaming of the assembly and the part is done to give every part a different identity so everyone can identify in which assembly this part is going to fit.

After doing all these things the model is sent for simulation and 2d detailing.

Points Need to Be Taken Care of While Finishing the Design:

The following are the points taken into consideration while finishing the design.

Hole Concentricity and Hole Sizes:

All part holes' concentricity and hole sizes are checked for easy assembly while finishing the parts.

Machining Area:

The machining area in every part should be defined and the machining area should be highlighted by using standard colour code. Machining is to be done on parts to properly Mount with mating parts. Machining only on desired faces reduces cost and saves time. Also, Machining increases the accuracy of dimension. So before going to simulation or detailing machining area should be defined.

Nominality:

All unit dimensions should be maintained nominal to facilitate easy assembly of the unit.

Holes Colouring Standard:

In a 3D finish hole coloring should be done because it helps to identify what type of hole it is. It depends on customer standards. Customer-specific colors like:

The Dowel hole should be given a blue color.

The threaded hole should be colored with yellow.

Counterbore, open hole should be given cyan blue color.

Pneumatic Lay outing:

The pneumatic layout is a collection of different pneumatic pipes that work as an inlet to the pneumatic cylinder. It should be done properly for the proper functioning of the units.

Gaps Checking:

The gaps between the different units are checked to ensure the proper individual working of different units.

Fasteners Implementation:

Fast should be implemented in all the units as per the requirement and load on the part.

Avoiding Clash Between Different Parts:

A proper gap should be maintained between units to avoid clashes between the different units.

Mylar Splitting as Per Panel Profile:

Mylar splitting for the panel profile should be confirmed while finishing the design.

Proper Renaming of Parts or Assemblies as Per the Standards:

Proper renaming of parts and assembly should be done while finishing the design and hence we can identify every part easily with Unique Identification.

ROUGH LOCATORS:

A rough locator is a part designed to guide the panel, to locate the car panel onto the pins accordingly. A rough locator can be of standard part or a make part.

Rough locators also work as Poka yoke. Poka-yoke is a Japanese concept used for mistake-proofing.

Rough locators are also used to help locate the workpieces in the automation process. Locating refers to the desired location where you want the workpiece to be when it is getting worked on either by a person a team or a robot.

The accuracy of the locating components directly affects the consistency and how the final product will come out. This is why these components are essential to our setup.

It can be also called the proofing method. Because without a rough locator, the part cannot be loaded in the correct position.

The rough locators are set according to the angle of the respective panel and hence the part can be loaded in a defined direction and orientation only.

Base unit:

The base unit is the fundamental component of the fixture because all other components are mounted over it so every fixture has a base unit. The base unit design is different according to the panel. Design of clamp system, location system, etc.

Trunking channel:

A trunking channel is a basically duct that accommodates all the pneumatic and electrical hoses and wires for the unit. It protects the wires/cables from damage.

Base plate:

The base plate is a machined plate of 25 to 40mm thickness made of steel and aluminum, on to which the holes are drilled to mount the individual units like clamp unit, pin unit, etc.,

Pedestal:

It is a component that connects the base plate to the floor plate. Pedestal is a standard part in general and it can be welded to the base plate.

Floor plates:

The floor plate is grouted to the floor with a fixed bolt on the ground. Floor plates are also called foundation plates.

Eyebolt:

An eye bolt is a bolt with a loop at one end. They are used to firmly attach a securing eye to a structure, so that ropes or cables may then be tied to it to lift the unit. The eye bolt should be placed such that it does not harm clamp/pin units.

Points Needed to Consider While Designing A Rough Locator:

The following are the points that need to be considered while designing the rough locator.

A rough locator should be placed at the edges of the car panel, which it has to guide.

The applicator has to be placed at the same angle of the car part edge with a minimum distance of 2-5 mm from the edge of the car part.

Prof locator should guide the panel in pin arresting direction.

The rough locator should start guiding the panel 10 to 15mm before the start of the pin engagement.

The applicator should be designed with an entry angle for the car panel. Generally, it ranges between 30-45 degrees.

A rough locator should be designed with two slots to mount the easy adjustment.

The slot should be in the direction of the car part guiding.

GUN STUDY:
Welding is predominantly used in automobile industries and requirements for fixtures that ease the welding process is a continuous development task in any industry. Car Body-In-White (BIW) is a complicated steel structure including 300~500 sheets with complex shapes that are assembled using welding in a high rhythm through 55~75 robotic work-stations. The foremost step taken before starting the design of the welding fixture is to arrive at the spot weld locations. The location and orientation of other critical units of the fixture including clamps, locators, etc., are decided based on the weld spot distribution. The weld spots for the Front door inner panel and Side bracket assembly are located as shown in Table 1 concerning the body line of the car. It includes the study of the weld gun (A portable device for semiautomatic welding of parts of various articles) which is going to be used for the operation depending on the size of the part, Thickness of the part, etc. It includes the study of the weld matrix & the weld point positions. There are two types of weld points: geo weld points which ensure the geometry of the assembly & and Re spot weld points which add strength to the already welded part.

The device used to make spot welding on the panel is called a Gun. The Gun may differ depending on the application. Fixtures will be designed by considering the weld spots on the panel. After designing the Fixture, the CAD file of the gun is placed on the weld spots to check whether the Gun is clear with the Fixture. After adjusting the Fixtures, the coordinates of the welds are taken for further operations of the Weld Gun. Points needed to consider during the gun study:

Weld gun study is a very time-consuming process, the entire welding cycle time study depends on the no. of spots & weld gun study.

The following are the points that need to be considered during gun study.

The axis of the weld spot along the welding direction must be normal to the weld surface.

The no. of weld spots for the panel, the time required to spot each weld & the total time required to complete all weld spots.

If we have one or more device models & we want to program, the behavior of each model in the work cell can be simulated over time. Instructions for each device are coded by giving sequences. The sequence defines the motion, manipulation & action of the devices. Based on the distance of each tag point from the home position, motion type, speed & acceleration one can obtain cycle time for each device assigned with sequences. This way robot cycle time is precisely calculated.

After sequencing all the devices, a simulation is run with “collision check” ON & made sure that the welding operation is collision-free.

Renaming and structuring of the design tree:
Renaming of the design tree is done. and structuring the design tree in a way that is simple to identify the units. some units used multiple times that are easy to
identify by its name.

BASE UNIT:

A base unit is a unit designed to mount all the other units of the tool, also other parts necessary for a tool like a pneumatic valve box, and trunking cable path will be mounted onto a base unit.

Below are some parts of a base unit in general.

Trunking channel

Base plate

Valve box

Measuring hole cover

Eye bolt.

Pedestal.

Weld bars.

Floor plate.

Typical Parts of a base unit:

The typical Parts of a base unit are:

Base Plate:

A base Plate is a machined plate of 25 to 40mm thickness made of steel and aluminum on which the holes are drilled to mount the individual units like clamp units. pin units etc of a tool.

There are three key benefits to a Base plate:

They can help to quickly and accurately tram in fixtures and vises.

They can hold large, complicated, or odd-shaped parts.

They protect the cast iron machine table.

Pedestal:

A pedestal is a part that connects the base plate to the floor plate. A pedestal is a standard part in general, and in some cases, it can be a welded frame integrated with the base plate.

A standard pedestal can be of different heights and different sizes.

Depending on the size of the base plate, the number of pedestals varies for load distribution.

A pedestal is of different types with different inclinations.

Trunking Channel:

The trunking channel is a standard part that will accommodate all the pneumatic and electrical hoses and wires for the units. The trunking channel includes all the pressure inlet cables going to the pneumatic parts of the fixture and protects them from damage while the operation is in process.

Valve Box:

The valve Box is a standard part that will contain all the valves for the pneumatic units. The valve box is the box which includes different solenoid valves. The pneumatic fixtures work on air pressure provided to it. So the arrangement of the air pressure inlet and outlet is done within this valve box. The trunking channel includes all the pressure inlet cables going to the pneumatic parts of the fixture and protects them from damage while the operation is in process.

Eye Bolt:

An eye bolt is a bolt with a loop at one end. They are used to firmly attach a securing eye to a structure, so that ropes or cables may then be tied to it.

Machinery eye bolts are fully threaded and may have a collar, making them suitable for use with angular loads up to 450. Eye bolts without a shoulder should not be used for angular loads. Heavy forged eye bolts with a continuous eye may be forged with an integral shoulder, allowing their use for heavy off-axis loads.

These are used for the transporting of the tool by inserting hooks into them. Some, hooks or forklift holes are also provided in some cases for transporting purposes.

Floor Plate:

Floor plates are grouted to the floor with fixed bolts on the ground. These are also called foundation plates.

There will be a clearance of 10mm maintained between the pedestal base plate and the floor plate.

This clearance will be used by the leveling screws, for leveling the entire tool.

Weld bars are to be used to weld the positions permanently after leveling is done.

A weld bar is a plate along the sides of the base plate of the pedestal.

Fundamentals Of a Base Plate Design:

The fundamentals of a base plate design are:

As a designer, it is important to know how big a base plate or bigger base welded structure will be handled during the fabrication & handling process. Special care needs to take care of flatness if the base size is very long.

A base plate size should cover all the units with its outer periphery including the opening.

A base plate is preferred to be designed concerning BCS coordinates.

A base plate should be drilled with datum holes / measuring holes in line with a pitch of 1000 mm in general.

The number of datum holes depends on the size of the base plate.

Datum holes should be drilled at nominal values of coordinates & in terms of 50 x 100. (In general) ex. X=100, Y 600, Z-250.

Datum holes should be drilled with a diameter 100 mm away from other units.

Datum holes should be covered with cover plates.

Depending upon the weight, eye bolt size is selected for lifting holes on the base plate Generally, 4 eye bolt provision is made You also need to select the location of the eye bolt considering the rope/ belts used while shifting the structure or complete fixture are not damaging any units (rest, clamp or location units) nearby.

Depending upon the component size & weight of the total units you can decide whether you need a fabricated base or just a plate. Mostly fabricated bases are made of square or rectangular tubes with plates.

Most OEM makes 4 dowel holes at 4 corners & put small aluminum plates marking the X Y&Z coordinates of dowel holes. If the base length is too long few OEMs' s follow the methodology of having holes at a 500 mm distance.

The best unit of the fixture must be strong enough so that the deflection of the fixture is as minimal as possible. This deflection of a fixture is called because of forces of welding, and clamping of the workpiece.

The base unit of the fixture should have the mass to prevent vibration & chatter.

The base unit may be built from simple sections so that other units may be fastened with screws or Welded as necessary. Those parts of the fixture that remain permanently with the fixture may be welded. Those parts that need frequent changing may be held with screws.

The base unit should be parallel to the floor to adjust this there should be provision for the height adjusting mechanism.

Typical parts of Base units:-

Base plate: A base plate is a machined plate of 25 to 40mm thickness made of steel and aluminum, on which the holes are drilled to mount the individual units like clamp unit, pin unit, etc., of a tool.

Pedestal: A pedestal is a part that connects the base plate to the floor plate. A pedestal is a standard part in general, and in some cases, it can be a welded frame integrated with the base plate.

A standard pedestal can be of different heights and different sizes.

Depending on the size of the base plate, the number of pedestals varies for load distribution.

A pedestal is of different types with different inclinations.

Trunking channel: A trunking channel is a duct that accommodates all the pneumatic and electrical hoses and wires for the units of the tool.

Valve Box: The valve box is a standard part that will accommodate the pneumatic valves for the units.

Eye Bolt: Eye bolts are used for the transporting of the tool, using lift hooks, Forklift holes will also be provided in some cases for transporting purposes.

Floor Plate: The floor plate is grouted to the floor with a fixed bolt on the ground. Floor plates are also called foundation plates.

There will be a clearance of 10mm maintained between the pedestal base plate and the floor plate.

This clearance will be used by leveling screws, for leveling the entire tool.

Weld bars are used to weld the positions permanently After leveling is done.

A weld bar is a plate along the sides of the base plate of the pedestal.

Weld bars: These bars are used to position the fixture. The Weld bar is a steel plate placed alongside side base plate of the pedestal.

Design Methodology:

The points that need to be accounted for while designing a Base Unit are as below:

Working Height: Depending upon the type of operation whether it is manual welding or robotic welding height of the base unit is decided. For manual welding fixture working height must be 850 to 1100mm for ease in welding operation for the operator.

The selection of Eyebolt depends upon the weight of the fixture. According to the weight of the fixture tapping for the eyebolt is provided on a base plate like M24 or M20. Generally, four eyebolts are provided on the base plate.

Depending on the of units, sizes, and weight bases are designed. base designs are made up of square or rectangular tubes or c channels with machined plates.

Generally, four dowel holes are provided at four corners of the base plate with their coordinates displayed on the aluminum plate

The base unit is designed in such a way that there is mon possibility of deflection vibration.

Checking Parameter	Action
Rename the design tree	Done
Mark Machining Area	Done
Nominality	Done
Holes coloring standard	Done

REST UNIT:

The rest unit is a unit designed to support the car panel using Mylar/ NC block/ rest component is rested only, no upper clamp or force is applied there. It is the simplest unit to design because it has fewer parts to design & the purpose is only resting of the car panel.

Because of the simplicity, the rest unit is combined with another unit to reduce the cost of the overall project.

It can be combined with a clamp unit to clamp as well as to rest the car panel. It can be combined with locating unit to locate as well as to rest the car panel. Also locating, clamping & Test units can be combined into one unit to reduce cost.

There is no cylinder attached to it. It has a rest Mylar, blade, and riser & below are different parts of the rest unit. The rest unit is also divided into simple support units, multiple support units & retractable support units.

Checking Parameter	Action
Rename the design tree	Done
Mark Machining Area	Marked
Nominality	Done
Holes coloring standard	Done

POWER CLAMP UNIT:

A clamp unit is a unit designed to clamp/hold the car panel with NC blocks/Mylars/rest by using a pneumatic cylinder. The clamp arm, finger, Rest/backup, L-block, shims, riser, and pneumatic cylinders are the typical parts of the clamp unit. Clamping force should be considered while designing a clamp unit. Usually clamp open position is 90o. Fingers are attached to clamp Mylar. In the Clamp unit, shim to one side is more than enough because it will restrict translation motion in an upward direction and downward direction only. There is another type of clamp unit known as the swivel type. There is a pivot pin around which the clamp arm rotates.

Clamping Guidelines:

Locating the workpiece is the first basic function of a jig or fixture. Once located, the workpiece must also be held to prevent movement during the operational cycle. The process of holding the position of the workpiece in the jig or fixture is called clamping. The primary devices used for holding a workpiece are clamps. To perform properly, both the clamping devices and their location on the work holder must be carefully selected.

Factors in Selecting Clamps:

Clamps serve two primary functions.

They must hold the workpiece against its locators.

The clamps must prevent movement of the workpiece.

The procedure of Clamping the Work Piece to the Panel:

Place the workpiece, supply air at the clamp side without installing the clamping block, and operate the clamp arm to the end of the clamp.

Under the above conditions, adjust the shim so that the space between the workpiece and the clamping block is about 0.5 mm. Theoretically, there is no clamping force for holding a workpiece under this condition.

To generate clamping force from the state described in step B, insert an additional shim. The thickness of the shim differs depending on the arm length and pressure, so please refer to the graph on front matter 3 as a guide. About 10% error may occur due to the difference in tolerance of the clamp cylinder body.

Considerations to be taken while designing a rest unit or a clamp unit:

Considerations to be taken while designing a Rest Unit or a Clamp unit are:

1. Study of process planning document:

The process document should contain the following information, which is necessary to design the clamp unit.

No sheet metal panels are to be welded.

Total no of spots.

Welding gun details if it is already recommended by the process engineer study it in details like shape and type.

Study the PLP (Principle Location Points) data along with the nearby spot data.

2. CAD Software:

If you are using any specific CAD software as per the customer requirement e.g., CATIA understand the customer guidelines on how to create the fixture, unit, weldment, and base fabrication. Once you have an understanding of CAD software methodology to be followed for the design of a single part, Unit assembly, and base then start the design by adding the panel assembly in your fixture or unit assembly.

3. Height Selection:

Take an overview of the working height if we have manual welding. For robotic welding also important to see the working height in consideration of the robotic gun, and turn table height if manual loading is done.

4. Gun Placement:

Put the proper gun at the spot location. Do the proper gun study and place the gun as per the GEO or re-spot decision and operator approach. Once the basic gun is placed considering the throat depth and throat gap start building the clamp and rest block at the PLP.

5. Panel section creation:

Take a section at PLP either in the clamp opening direction or the normal direction. Sections should be normal to the base. Panel section through X, Y, or Z direction passing through PL. The section will help in finalizing the shape of the clamp and rest block. Most importantly used for the finalization of gun shape.

6. Finalization of a base plate:

Consider the following things before deciding on the base plate.

Height of maximum and minimum weld spot from the floor.

No gun arm should touch the base plate.

The operator is ergonomic while accessing all the spots.

7. Construction of Rest and Clamp Block:

If standard Mylar has to be used then select the proper blank size as per the requirement consider 0.5 mm above the panel.

8. Clamp cylinder selection:

Select the clamping cylinder as per the pivot point distance from the PLP. You may choose various cylinders 50 Dia, 63 Dia, and 80 Dia. as per the requirement.

9. Clamp and Rest block creation:

Create a clamp or rest block as per the company guidelines.

Many companies have sizes of clamp blocks as 20x20 mm and no mounting screws and dowels. Many use 20x20 size rest or clamp block with one screw and 2 dowels and few use with 2 screws and 2 dowels. Materials of the clamp block and rest block are to be decided as per the A class panel or B class. Most of the exterior panels holding Teflon material are used. Otherwise, steel is used with heat treatment. Sometimes Aluminium blocks are also used. Start construction of the mounting plate or fabrication structure as per the company standard to make the connection with the base plate.

10. Riser:

As per OEM, Tier 1 standards use different standards mounting risers. Do not forget to add the 5 mm shim.

11. Rough Locator or position sensor mounted on clamp unit:

If you are combining a rough locator or part sensor bracket with the clamp unit. Taking necessary care means a distance of the rough locator from the panel.

12. Hardware:

Add all the hardware screws, dowels, and washers as per the size.

13. Clamp Open Position:

Check all the clamps open, and gun open positions and ensure that there is fouling with panels or any other surrounding units.

Checking Parameters:

Checking Parameter	Action
Rename the design tree	Done
Mark Machining Area	Marked
Mylars Splitting as per Panel profile	Done
Hole Concentricity	Done
Nominality	Done
Holes coloring standard	Done

PIN UNIT:

A pin unit is a unit designed to locate the car panel using pins. There are two types of pin units. They are:

Fixed pin unit

Retractable pin unit

Single Rod

Dual rod

Below are the different parts of a fixed pin unit.

Pin

Pin retainer

Shims/Spacers

Blocks

Blade/Adaptor plate

Riser

Cylinders

Fundamentals of Pin Unit Design:

It is necessary to have 2 pins to locate a car panel & here one pin must arrest 4 ways (4 translational) & other must arrest 2 ways i.e. 2 rotational) of a car panel.

The axis of the car panel hole & the axis of the pin should be the same. The pin tolerance for a geo pin will be of closer tolerance i.e. 0.15mm & for a re-spot pin is -0.28mm

The pin should engage 3 to 5 mm from the car panel entry surface.

All pins should be accommodated with 2-way adjustable shims irrespective of the direction of arresting.

Round pins should be used in case of 4-way arresting of car part if the hole is round.

Round pins can be used for 2 way arresting of car parts only if the hole is slot.

Diamond pins should be used in case of 2 way arresting of car part if the hole is round

Diamond pins should be used in case of 4-way arresting of car part if the hole is slotted.

FIXED PIN UNIT:

Below are the different parts of a fixed pin unit.

Pin

Pin retainer

Shims/Spacers

Blocks

Blade/Adaptor plate

Riser

Checking Parameters:

Checking Parameter	Action
Rename the design tree	Done
Mark Machining Area	Marked
Hole Concentricity	Done
Nominality	Done
Holes coloring standard	Done

SWIVEL CLAMP UNIT:

Clamp Unit:

A clamp unit is a unit designed to clamp/hold the car panel with NC blocks/Mylars/rest by using a pneumatic cylinder. The clamp arm, finger, Rest/backup, L-block, shims, riser, and pneumatic cylinders are the typical parts of the clamp unit. Clamping force should be considered while designing a clamp unit. Usually clamp open position is 90o. Fingers are attached to clamp Mylar. In the Clamp unit, shim to one side is more than enough because it will restrict translation motion in an upward direction and downward direction only. There is another type of clamp unit known as the swivel type. There is a pivot pin around which the clamp arm rotates.

Parts of a Clamp Cylinder:

Clamp cylinder: In the clevis clamp unit, a swivel-type cylinder is used. Pneumatic Cylinders are mechanical devices that use the power of compressed gas to produce a force in a reciprocating linear motion. Like hydraulic cylinders, compressed gas or fluid forces a piston to move in the desired direction. The piston is a disc or a cylinder, and the piston rod transfers the force it develops to the object to be moved. Engineers sometimes prefer to use pneumatic because they are quieter, cleaner, and don't require large amounts of space for Fluid storage. Because operating fluid is a gas and its leakage from the pneumatic cylinder will not only drip out but, contaminate the entire surroundings. Making pneumatic more desirable where cleanliness is a requirement. Once actuated, Compressed air enters into the tube at one end of the piston and imparts force on the piston in the other direction. Consequently, the piston gets displaced.

Rest Mylar: A Mylar is an NC block that is mounted on the clamp arm of the cylinder and presses the car panel to the Rest Mylar, therefore holding the car panel.

Clamp Myler: A Clamp arm is a make part, it is made as per the positioning of the clamping cylinder, Stopper, and shims. The clamp arm is made from Hard material.

Clamp Arm: The distance between the pivot point and the cylinder mount should be 50mm. This is necessary because the cylinder stroke is 100 mm and it must be achieved when it is at 900 position and the clamp arm mounting hole must be in line with the cylinder.

Stoppers: The function of the stopper is to restrict the movement of the clamp from going beyond the limit. The stopper is mounted between the Clamp arm and the Blade. The stopper has two parts, a Male stopper and a Female stopper. The Male stopper is attached to the clamp arm and the Female Stopper is attached to the Blade. When these two Parts meet, they restrict the motion.

Blade: A blade is a made part designed according to the position of the riser, clamp cylinder, Clamp arm, Rest Mylar, and stopper.

Riser: A Riser is a standard part or a make part that provides height to the pin unit and clamp unit as per the requirements. The riser should have adequate strength so it can sustain the load of the car panel, Clamping cylinder, and Blades.

Bushes: Bush is a friction-type bearing. It is lubricated with grease, and oil. It permits relative motion between mating parts. It is made of hard material also ID and OD are precisely machined or grinded. It is Press fitted and after worn out it is replaced with a new one instead of replacing another part which saves cost. Mostly Phosphor bronze or gunmetal is used for manufacturing bushes.

Shim Plates: In the Fixture, we are providing tolerance to each part mostly manufactured. Those tolerances tend to stack up and Reflect together. To avoid that we use shims so we can easily adjust after assembly so whatever is stacked up there we will rectify it through shims. Shims come in thicknesses of 0.1,0.2,0.5, etc. We provide a shim to accommodate the clamp as well as rest mylar in two directions. Clamp & rest mylar can be adjusted in one direction only i.e., up or down. Also, a two-way shim was provided for locating the pin to accommodate adjustment.

Design of Swivel Clamp unit:

Study the PLP (Principal location Points) data along with the nearby spot data.

Depending on the angle of the cross-section. Mylars will be having shimming either in one direction or in 2 directions. The general thumb rule is if the section is inclined more than 150 or the clamping surface is a 3D profile then 2-direction shimming is provided

Take an overview of the working height if you're having manual welding. For robotic welding also it's important to see the working height in consideration of the robotic gun, and turntable height if manual loading is done.

Put the proper gun at the spot location. If the process engineer has a gun shape stick to the X, C, or Y type of gun. Do the proper gun study and place the gun as per the Geo or re-spot decision and operator approach. Once the basic gun is placed considering the throat depth and throat gap start building the clamp and rest block at the PLP.

Panel section creation: Take a section at PLP either in clamp opening direction or normal direction Sections should be normal to base. Panel section through X, Y, or Z direction passing through PLR Section will help it finalizing the shape of the clamp and rest block. Most importantly used for the finalization of gun shape.

Finalization of a base plate plane: Consider the following things before deciding the base plate Height of the maximum and minimum weld spot from the floor. No gun arm should touch the base plate. The operator is ergonomic while accessing all the spots.

Construction of Rest and Clamp block: If standard Mylar has to be used (Few companies make standard height and length of steel blank with few holes and dowels for clamping) they select the proper blank size as per the requirement considering 0.5 mm above the panel.

Select the clamping cylinder as per the pivot point distance from the PLP Once the clamp and rest block are built, start construction of the mounting plate or lubrication structure as per the company standard to make the connection with the base plate, shimming is 2mm solid+3mm shim pack. In a few companies, 3mm shims are used. Make connection plate between rise and Mylar Material can be C45, Teflon, Aluminium, or S-Gurn as per the customer requirement Generally S Gurn Mylars are made of more thickness.

Factors to be considered while designing a clamp unit:

There should be adequate space between the cylinder and other parts like the riser, or car panel because the cylinder moves or swings while opening and closing.

A pin clam unit is used where two panels or components are located and clamped for welding.

Clamp make is in such a way that it clamps two car panels at once.

Every clamp Mylar should have rest Mylar.

The clamp unit has shims in only one direction.

All parts should snap and butt properly to each other.

Make sure that parts of the clamping unit are min 10 to 12 mm away from the car panel, so they don't damage the car panel.

The design tree should be structured in a way that makes a part on the top and follows the standard part.

Avoid any clash, it will not raise issues at assembly.

The product design should be in such a way that it will be easy to make, assemble, and quality check.

We should preferably use quick-acting clamps, the clamping method will not damage the workpiece. The clamp should be open in such a way that the clamp arm moves away from the operator.

There must be adequate clearance for loading and unloading. So, the process becomes fast and easy. The Size variation must be accepted.

Avoid sharp edges and corners, they can harm the operators and cause a serious injury. Provide chamfer or fillet to the corner.

The fixture must possess sufficient rigidity and robustness. It should not vibrate as it can lead to unwanted movement of the workpiece and tools.

Must ensure security in the operation.

Checking Parameter	Action
Rename the design tree	Done
Mark Machining Area	Marked
Hole Concentricity	Done
Nominality	Done
Holes coloring standard	Done
Mylar Splitting as per panel profile	Done

RETRACTABLE PIN UNIT:

A retractable pin unit is a unit designed to locate the car panel using pins, but the entire pin package parts will be mounted on the retractable pneumatic cylinder.

Cylinders:

SZK_40_1_BR3_A14_T12_TUENKERS:

The pneumatic cylinder in aluminum block design with a precision guide of the piston rod, secured against rotating. Compact Housing Made from high-strength aluminum with mounting options on several sides. Drive mechanism with circular section cylinder for the thrust forces and extraction forces of approx.350/250N.Total strokes 40mm integrated inductive sensitive sensing system.

Checking Parameter	Action
Rename the design tree	Done
Mark Machining Area	Marked
Hole Concentricity	Done
Nominality	Done
Holes coloring standard	Done

IMAGES OF ALL THE UNITS USED IN THE ASSEMBLY AFTER 3D FINISHING: