P-CLAMP ELECTRICAL DEFINITION, CONNECTOR AND BACKSHELL'S ASSEMBLY, COT TUBES & CATALOGUE

WIRING HARNESS ROUTING AND PACKAGING RULES

 

OBJECTIVE: The objective of this project is to analyze and comprehend various models of clips, backshells, and corrugated tubes, and transform the provided CAD data file of the P clamp into an electrical support component. Additionally, the back shell will be converted into an electrical back shell using the electrical Part Design workbench within the CATIA V5 tool. Furthermore, several corrugated tubes will be created based on the given data and added to a new catalogue called "Slit COT".

 

In this project, the focus is on studying the different designs and configurations of clips, backshells, and corrugated tubes, which are essential components in electrical systems. By utilizing the electrical Part Design workbench in CATIA V5, the CAD data file of the P clamp will undergo modifications to transform it into an electrical support component. This conversion process involves incorporating specific electrical design features and ensuring compatibility with the overall electrical system.

 

Similarly, the back shell will be redesigned and transformed into an electrical back shell to provide protection and connectivity for electrical connectors. The electrical Part Design workbench in CATIA V5 enables precise modelling and adaptation of the back shell, taking into account the electrical requirements and standards.

 

Furthermore, the project involves creating various corrugated tubes based on the provided data. These tubes are crucial for organizing and protecting electrical cables and wires within the system. By leveraging the capabilities of CATIA V5, the corrugated tubes will be accurately modelled, considering factors such as size, flexibility, and compatibility with different cable diameters.

 

To streamline future design processes and facilitate easy access to the newly created corrugated tubes, a new catalogue named "Slit COT" will be established. This catalogue will serve as a repository of the different corrugated tube designs, allowing designers and engineers to efficiently select and incorporate the appropriate tube for their specific electrical system requirements.

 

Overall, this project aims to enhance the understanding of clips, backshells, and corrugated tubes in electrical systems. By utilizing the electrical Part Design workbench in CATIA V5, the CAD data file of the P clamp will be transformed into an electrical support component, while the back shell will be converted into an electrical back shell. Additionally, the creation of various corrugated tubes and their inclusion in the "Slit COT" catalogue will streamline future design processes and promote efficient electrical system integration.

 

INTRODUCTION: 

Clips: In the context of automotive wiring harnesses, a clip refers to a small device or fastener used to secure and organize the various wires and cables within the harness. Clips are typically made of durable materials such as plastic or metal and are designed to hold the wires in place, preventing them from moving or becoming tangled. They play a crucial role in maintaining the integrity and reliability of the wiring harness.

Types of Clips Used in Automotive Wiring Harnesses:  

• Adjustable P-Clips. Details.
• Anchorhead Disc Clip. Details.
• Cable Harness Clip – Plain. Details.
• Cable Harness Clip- Screw. Details.
• Dome Fir Tree Mount Clip. Details.
• Dome Push Mount Clip. Details.
• Fir Tree Push Clamp. Details.
• Fixed P-Clips
• Self-Adhesive Cable Clips

        

These clips help organize our wire harness and electrical system, keeping everything neatly in place. Please note that the specific types of clips used can vary depending on the specific requirements of the automotive wiring harness.

Clamps: Clamps are another type of supporting part used in automotive wiring harnesses. They are used to secure the harness to the vehicle's structure, such as the body or chassis. Clamps are usually made of metal and come in various shapes and sizes to accommodate different mounting requirements. They provide stability and ensure that the wiring harness remains securely attached, preventing any movement or damage that could result from vibrations or other external forces.

1. Fir Tree Push Clamp

2. Hinged P-Clamp

   

 

P-Clamp: The P-Clamp is a specific type of clamp that is widely used in the automotive industry for various purposes, particularly in wiring harnesses. It is named after its distinctive shape, which resembles the letter "P". The P-Clamp consists of a metal base with a rubber coating and a hinged or fixed loop that forms the shape of the letter "P". This loop is designed to securely hold and route wires or cables within the harness.

Purpose and Function: The primary purpose of the P-Clamp is to provide a secure mounting point for the wiring harness, ensuring that the wires are properly organized and protected. The rubber coating on the metal base prevents the clamp from coming in direct contact with the wire it is clamping, reducing the risk of damage to the wire's insulation. This prevents electrical shorts, abrasion, and interference, ensuring the reliability and longevity of the wiring harness.

Installation: The P-Clamp is typically installed by attaching the metal base to a suitable mounting surface, such as a vehicle frame or body panel, using screws, bolts, or adhesive. The rubber coating on the base acts as a cushion and prevents the metal from directly touching the wire. The loop of the P-Clamp is then used to hold the wires or cables in place. It can be either hinged, allowing for easy insertion and removal of wires, or fixed, providing a more permanent and secure hold.

 

Material and Design: The metal base of the P-Clamp is typically made from materials such as stainless steel or aluminium, which provide strength and durability. The rubber coating is added to the base to provide insulation and protect the wire's insulation from damage. The rubber coating is usually made from materials such as EPDM (Ethylene Propylene Diene Monomer) rubber, which offers excellent electrical insulation properties and resistance to environmental conditions.

Size and Variations: P-Clamps come in various sizes to accommodate different wire diameters and harness configurations. They are available in a range of widths, depths, and loop sizes to suit specific wiring needs. The rubber coating may also vary in thickness and hardness, depending on the application requirements and the level of protection needed for the wire.

 

Mounting Options: P-Clamps offer versatility in mounting options. They can be attached to flat surfaces using screws or bolts, or they can be mounted on tubes or pipes using specialized brackets. This flexibility allows for efficient routing and securing of wires in various locations within the vehicle.

Industry Standards and Regulations: P-Clamps used in automotive wiring harnesses must conform to industry standards and regulations to ensure safety and reliability. These standards may include requirements for material strength, electrical insulation, and resistance to environmental conditions such as temperature, moisture, and chemical exposure.

 

In summary, the P-Clamp with a rubber coating is a specialized type of clamp used in automotive wiring harnesses. Its purpose is to securely hold and route wires while preventing damage to the wire's insulation. With its metal base and rubber coating, the P-Clamp provides insulation, protection, and reliability. It comes in various sizes and can be mounted in different ways, offering flexibility in wire routing. Compliance with industry standards ensures its safety and performance in automotive applications.

 

1. Define the P-Clamp as an Electrical Support Part using the Electrical Part Workbench:

We will download the CAD file for our P-Clamp from the following link:

https://drive.google.com/file/d/1cL9NiCnMl1I0SGlRESUZwdjSP5_9eAlb/view

 

 

After that, we'll open the P-Clamp in CATIA V5 as shown below:

 

This is the Rubber Coating Section of the P-Clamp that prevents the clamp from coming into direct contact with the wire clamping, reducing the risk of damage to the wire's insulation. This prevents electrical shorts, abrasion, and interference, ensuring the reliability and longevity of the wiring harness. 

 

This is the metallic section of the P-Clamp that has holes in it that can be screwed in to ensure the appropriate fitment necessary to hold the wire bundle firmly in its place. 

 

Next, we're going to define this 3D CAD Model of P-Clamp into an Electrical Support Part by following the necessary steps shown below:

INITIAL TREE STRUCTURE:

1. To thoroughly analyze the P-clamp clip model and understand how the cable or bundle passes through it, we need to identify the entry, exit, base, and mechanically connected faces. Begin by downloading the neutral data file (STEP/IGS file) of the P-clamp from the provided source and opening it in the CATIA Part workbench.

2. Next, define the centre points of the entry and exit faces by selecting the appropriate edges and creating planes that are parallel through these points. This step allows us to accurately determine the entry and exit points of the cable or bundle within the P-clamp.

3. To establish the base plane, directly establish the plane from the base face of the P-clamp. This ensures that the base plane aligns with the underlying structure of the clamp.

4. Now, switch to the CATIA Electrical Part Design workbench and utilize the "Define Support Part" command to define the P-clamp model as an electrical support. Apply this command to both the entry and exit faces of the P-clamp. By doing so, the CAD part model is converted into an electrical support model. 

By following these steps, we can thoroughly examine the P-clamp clip model, understand the path of the cable or bundle through it, and identify the entry, exit, base, and mechanically connected faces. The transition to the Electrical Part Design workbench allows for the definition of the P-clamp model as an electrical support, facilitating its integration within electrical systems.

 

 

2. Define the Back-Shell as an Electrical Back-Shell using the Electrical Part Workbench:

 

TYPES OF BACKSHELLS:

1. 45° ENVIRONMENTAL BACKSHELL WITH CABLE CLAMP

 

2. 90° ENVIRONMENTAL BACKSHELL WITH CABLE CLAMP

 

3. STRAIGHT ENVIRONMENTAL BACKSHELL WITH CABLE CLAMP

 

EXPLODED VIEW OF A TYPICAL BACKSHELL:

STRAIGHT ENTRY BACKSHELL:

 

 

ENVIRONMENTAL BACKSHELLS:

 

 

NON-ENVIRONMENTAL BACKS SHELLS:

 

ENVIRONMENTAL EMI/RFI BACKSHELL:

Back-shells, also known as connector back-shells or cable entry back-shells, play a crucial role in automotive wiring harnesses. They are protective components that provide strain relief, sealing, and shielding to ensure the reliability and durability of electrical connections and cables.

 

The primary function of a back-shell is to protect the connection point between the connector and the cable. It helps to prevent stress, strain, and damage to the wires and terminals by providing support and strain relief. Back-shells also offer protection against external elements such as moisture, dust, dirt, and vibrations, which can cause connection failures and electrical issues.

 

In addition to protection, back-shells also provide shielding to minimize electromagnetic interference (EMI) and radio frequency interference (RFI). This is especially important in automotive applications where there are numerous electrical systems operating in close proximity, such as engine compartments and dashboards.

 

There are several types of back-shells widely used in the automotive industry. Here are a few examples:

 

1. Straight-Entry Back-Shell: This type of back-shell provides a straight cable entry and is commonly used in applications where the cable needs to be routed directly from the connector without any bends or twists. It offers a compact and streamlined design.

 

2. 90-Degree Back-Shell: These back-shells feature a 90-degree cable entry, allowing the cable to be routed at a right angle to the connector. They are ideal for applications where space is limited, and a right-angle bend is necessary.

 

3. Environmental Back-Shell: These back-shells are designed to provide enhanced protection against environmental factors such as moisture, dust, and chemicals. They often feature a sealing grommet or boot to ensure a watertight or dust-tight seal.

 

4. Strain Relief Back-Shell: This type of back-shell focuses on providing excellent strain relief to the cable. They typically feature a clamping mechanism or a cable tie attachment point to secure and relieve strain from the wires.

 

5. EMI/RFI Shielded Back-Shell: These back-shells incorporate shielding materials, such as conductive metals or coatings, to minimize electromagnetic interference and radio frequency interference. They are commonly used in applications where signal integrity is critical, such as in high-frequency communication systems.

 

6. Heat-Shrink Back-Shell: Heat-shrink back-shells are made from heat-shrinkable materials that, when heated, shrink and conform to the cable and connector, providing a secure and protective covering. They offer excellent sealing and strain relief properties.

 

These are just a few examples of back shells used in automotive wiring harnesses. The choice of back-shell depends on various factors such as the application requirements, environmental conditions, cable routing, and connector type. Automotive manufacturers and suppliers offer a wide range of back-shells to meet the specific needs of different electrical systems in vehicles.

 

 

Now, we're going to define our Backshell as an Electrical Backshell by following the steps mentioned below:

To begin the process, download the neutral data file (STEP/IGS file) of the back shell from the provided source, which is the TE Connectivity website. Open the downloaded file in the CATIA Part workbench.

We'll thoroughly study the back shell model to understand the different faces involved, such as the back shell connection point, bundle connection point, and mechanically locking sides. This analysis allows for a comprehensive understanding of the back shell's design and functionality.

 

Create the necessary geometries, such as the centre points of the back shell connection point and bundle connection point, by selecting the appropriate edges. Additionally, establish an axis on the back shell connection point, aligning it with the same axis direction as the compatible mating part. Ensure that the Y axis points towards the back shell connection point (mating point) direction, while the X axis points towards the side of the locking mechanism.

 

Now, switch to the CATIA Electrical Part Design workbench and utilize the "Define Back Shell" command to define the model as an electrical back shell part. This step allows for the integration of electrical properties and functionality into the back shell design.

 

To define the back shell connection point, specify the representation as the back shell connector point. Select the face of contact, set the coincidence direction as the Y axis, and establish the orientation direction as the X axis. This ensures accurate alignment and connectivity of the back shell within the electrical system.

 

Similarly, use the command available in the Electrical Part Design workbench. Select the face of the bundle entry side and the previously created bundle centre point to define the bundle connection point of the back shell. This step ensures proper integration and compatibility with the cable or bundle.

By following these steps, the back shell part file is successfully converted into an electrical part file, incorporating all the necessary electrical properties and functionalities. This process ensures seamless integration of the back shell within the electrical system.

 

Now, we will follow the same instructions to define another back-shell electrically as shown below:

Back-Shell's Name: C-1546350-2

Back-Shell's Download Link: https://www.te.com/usa-en/product-1546350-2.html 

     

 

Next, we'll define a Back-Shell and connect it with a compatible Connector as  shown below:

90-Degree Back-Shell's Name: C-1011-244-0805

Back-Shell's Download Link: https://www.te.com/usa-en/product-1011-244-0805.html 

 

Straight-Entry Back-Shell's Name: C-1011-243-0805

Back-Shell's Download Link: https://www.te.com/usa-en/product-1011-243-0805.html

 

Connector's Name: C-DT04-08PA-CE09

Connector's Download Link: https://www.te.com/usa-en/product-DT04-08PA-CE09.html

 

 

 

90-degree Back-Shell defined electrically as Backshell with Backshell Connection Point and Bundle Entry Point:

 

Straight-Entry Back-Shell defined electrically as Backshell with Backshell Connection Point and Bundle Entry Point:

 

 

The connector is defined electrically with the Connector's Connection Point, Bundle Entry Point and Backshell Connection point as shown below:

 

 

Now, we're going to create a new product file and import these existing components. We're going to go to the Electrical Assembly Design Workbench use the 'Connect Electrical Devices' under the 'Electrical Connection Point Definition' Toolbar click on the Backshell and then on the Connector. They'll find a suitable point for assembly on their own defined according to our predefined backshell connection points with their respective axes as shown below:

 

This was the connection between 90-Degree Back-Shell C-1011-244-0805 & Connector C-DT04-08PA-CE09

 

Now we're going to disconnect this assembly using the Disconnect Electrical Devices command and then import the 

Straight-Entry Back-Shell named as C-1011-243-0805 as shown below:

 

From the above images we can clearly see that the connector is compatible with both backshells and using the Electrical Assembly Design Workbench we can assemble whichever backshell we need for our requirement. 

 

 

Next, we're going to create Corrugated Tubes or COT Tubes as per the requirement shown below:

 

   

Corrugated tubes, also known as COT tubes (Corrugated Optic Tubes), are commonly used in wiring harnesses as protective coverings for cables and wires. They provide several important benefits, including mechanical protection, flexibility, strain relief, and organization of cables. Here's a detailed explanation of each aspect:

 

1. Mechanical Protection: Corrugated tubes are designed to protect cables and wires from various mechanical hazards. They act as a physical barrier against abrasion, cuts, impacts, and other potential damages that can occur during the installation, operation, or maintenance of the wiring harness. The corrugated structure of the tube provides rigidity and strength, ensuring the cables inside are shielded from external forces.

 

2. Flexibility: One of the key advantages of corrugated tubes is their flexibility. They can be easily bent, twisted, and routed along complex paths, allowing for efficient cable management and installation in tight or irregular spaces within the vehicle. The flexibility of the tubes helps to accommodate the movement and vibration of the cables while maintaining their protection.

 

3. Strain Relief: Corrugated tubes offer excellent strain relief properties. They can absorb and distribute the forces and stresses that occur due to cable movement, temperature variations, or mechanical vibrations. By providing strain relief, the tubes help to prevent damage to the cables and maintain the integrity of the electrical connections, ensuring reliable and durable performance.

 

4. Cable Organization: Wiring harnesses often consist of multiple cables and wires. Corrugated tubes help in organizing and grouping these cables, making the harness more manageable and easier to install, maintain, and troubleshoot. Keeping the cables neatly organized within the tube, it reduces the chances of tangling, crossing, or interference between the wires, further improving the overall reliability of the harness.

 

5. Compatibility with Different Environments: Corrugated tubes are designed to withstand various environmental conditions that vehicles may encounter. They are typically made from materials that offer resistance to temperature extremes, moisture, chemicals, and UV radiation. This ensures that the cables and wires remain protected and unaffected by external factors, even in harsh conditions such as engine compartments or undercarriage areas.

 

6. Ease of Installation and Maintenance: Corrugated tubes are designed for ease of installation and maintenance. They can be easily cut to required lengths, split for adding or removing cables, and resealed. This flexibility allows for efficient installation and future modifications or repairs to the wiring harness.

 

In CATIA V5 Electrical Workbench, we can create and model corrugated tubes to simulate their appearance and fit within the wiring harness. The software offers tools and features for designing and manipulating the shape, dimensions, and properties of the tubes. This allows designers and engineers to visualize the interaction between the tubes and the cables, ensuring proper fit, routing, and protection within the wiring harness assembly.

 

By utilizing corrugated tubes in the design of wiring harnesses, automotive manufacturers can enhance the overall reliability, durability, and performance of the electrical systems in their vehicles. The tubes provide essential protection, flexibility, and organization for the cables, ensuring efficient operation and minimizing the risk of electrical failures or malfunctions.

 

 

First, we're going to create a new catalogue document in the CATIA as shown below:

Then, we're going to click on the 'Add Family' icon and create a new catalogue family as shown below:

 

It'll open up a dialogue box named 'Family Definition' where we'll provide the specified name of the family which is 'Slit COT' In our case and provide the required type for the family which is 'Conduit' as per our requirement. 

Now, we'll save this catalogue document at the desired location. 

 

Next, we're going to open the 'Options' menu under 'Tools' as shown below:

Then, we'll go under 'Equipments & Systems' and then we'll click on 'Electrical Harness Installation'. We'll see an option to add a catalogue under 'General' and hence we'll click on 'Add' go to the location of our saved catalogue and double click on the catalogue to add it as shown below:

Now, we'll click on 'OK' and start creating our COT Tubes as per design guidelines. To create a COT Tube, first, we'll open a new Part File and move on to the Electrical Part Design Workbench. 

After clicking on this icon, we'll click on the Part Name as shown below:

It'll open up a dialogue box named 'Define Protection Part' and we'll provide the value of the parameters that are provided to us to create COT tubes pertaining to those design requirements. 

In the above table, we're provided with the names of our COT Tubes and their values of Inner diameter, Thickness of each COT Tube and outer diameter which is actually 2* thickness + Inner Diameter. All the values expressed here are in millimetres (mm). 

So, for our first case, we'll fill the values as shown below:

In general, the Bend Radius should be 1.5 times the original diameter's value but it can vary depending on the flexibility of the COT Tube's material. In our case, we're considering 1.5 times the value of the Inner Diameter. 

Let's dive into details about each aspect to determine what are the factors that are needed to be considered to create a corrugated tube in the dialogue box shown above. 

Name: This parameter allows us to provide a name for the COT Tube we are creating. It helps in identifying and referencing the specific type of tube in our design.

Type: CATIA V5 Electrical Workbench offers two options for the Type parameter: corrugated tube and tape. Since we want to create corrugated tubes, we will select the corrugated tube option.

Inner Diameter: The Inner Diameter parameter refers to the size of the hollow space inside the corrugated tube. we can specify the desired value based on our design requirements and the size of the cables or wires that will be routed through the tube.

Thickness: The Thickness parameter determines the wall thickness of the corrugated tube. It is important to consider the thickness based on the level of protection and mechanical strength we need for the cables. Thicker walls provide increased protection but may also reduce flexibility.

Bend Radius: The Bend Radius parameter defines the minimum radius that the corrugated tube can bend without risking damage to the cables inside. It is essential to choose an appropriate bend radius to prevent excessive stress or strain on the cables. The bend radius should be large enough to avoid sharp bends that could lead to wire breakage or insulation damage.

Inner Section and Linear Mass: These parameters are automatically calculated by CATIA V5 based on the provided Inner Diameter and Thickness values. The inner Section refers to the cross-sectional area of the corrugated tube, and Linear Mass indicates the mass of the tube per unit length. These values help in determining the physical characteristics and properties of the tube.

Line type: The Line type parameter allows us to select the desired line style or pattern for the visual representation of the corrugated tube in the CATIA V5 model. It is a graphical attribute that helps differentiate the tube from other components in the design.

Light Geometry: The Light Geometry option is a setting that can be checked or unchecked. When checked, it enables a simplified representation of the COT Tube in the CATIA V5 model, reducing the computational load and improving the software's performance. This setting is particularly useful when working with complex assemblies that contain numerous COT Tubes, as it helps maintain a smooth workflow.

By carefully configuring these parameters in CATIA V5 Electrical Workbench, we can create accurate representations of COT Tubes and incorporate them effectively into our wiring harness design.

Next, we'll click on 'OK' as we'll see our COT Tube that is created as shown below:

 

We can use the 'Measure' tool to measure the radius and diameter of our COT Tube as shown below: 

After creating each COT Tube, we've to add that COT Tube in the Catalogue that has been created named 'Slit COT' as shown below:

If we don't perform the above operations we won't be able to use the COT Tube from any catalogue for further operation. 

 

Now, we're going to save this particular COT Tubes and create the rest of the COT Tubes in similar fashion as shown below:

20mm COT: 

 

35mm COT:

 

10mm COT:

 

 

5mm COT:

 

Now, if we want to use these Corrugated Tubes or COT Tubes as Protective Coverings we have to go to the Electrical Wiring Harness Installation Workbench and click on the icon as shown below and then click on the icon to browse towards the desired location where our catalogue is saved as shown below:

 

After clicking on the 'Slit COT' catalogue's icon, we'll see that all the COT Tubes that we have created are present inside that catalogue and hence these COT Tubes can be used to provide protective coverings on the suitable wire harness bundles.