Cable glands play a crucial role in connecting cables to electrical equipment. There are various types of cable glands available, each with its own unique materials, designs, and applications. As a reputable cable gland manufacturer and supplier, AerosUSA serves businesses across various industries. We provide cable glands that meet the specific demands of your situation.
Cable Glands Explained
A cable gland is a small device used to connect an electrical cable to equipment such as automation systems, electrical systems, instrumentation tools, and control devices. These glands come in different sizes to accommodate cables ranging from 1-75 millimeters in diameter. They consist of five parts: a sealing nut, locknut, washer, body, and seal. The assembly securely fastens the cable to the equipment’s threads.
Cable glands serve three important functions:
- Securing the cable: Cable glands ensure a firm connection between the cable and the equipment.
- Relieving cable strain: These glands attach at an angle to help the cable resist pulling forces that could damage the wires.
- Sealing the cable: Cable glands provide a seal that protects the cable and equipment from dust, debris, and moisture.
Cable Gland Materials
The performance of a cable gland depends on its material. Manufacturers use various metallic and non-metallic materials to design cable glands.
Metal
Metal cable glands are made from stainless steel, nickel-plated brass, or aluminum. These materials provide stability and durability, making them ideal for applications that require a strong connection. Metal cable glands also offer thermal conductivity and resistance to corrosion. They are commonly used in medical and chemical equipment, information technology devices, and power equipment.
Plastic
Plastic cable glands are stable and versatile, offering a cost-effective solution in applications that don’t involve extreme conditions. Most plastic cable glands are made from materials like polyamide or nylon, which resist corrosion in most environments. They are commonly used in telecommunications, marine applications, and equipment that uses flex cables.
Armor Compatibility
In addition to materials, cable glands can also be categorized based on their compatibility with different types of cables. Two common categories are armored and unarmored cables.
Armored Cables
Armored cables feature a protective layer between the interior wires and the exterior sheathing. The armor is typically made of durable materials such as metal, fiber yarn, or polyethylene. By covering the interior components, armored cables ensure durability in applications that test the cable’s mechanical strength. These cables are slightly larger than standard cables and require specific size accommodations from the cable gland. Additionally, they feature a clamping or locking mechanism that terminates the cable’s mechanical and electrical components and connects to the armor.
Unarmored Cables
Unarmored cables are standard variations used in many common applications. Unlike armored cables, they lack additional protective measures, making them less expensive and suitable for low-risk applications. However, unarmored cables still include outer seals that prevent ingress and retain the cable’s strength. They are available in all standard sizes and are compatible with standard cable glands.
Cable Glands for Specific Applications
There are several categories of cable glands that cater to specific applications. The four primary application-specific types of cable glands include:
- Electromagnetic Compatibility (EMC) Glands
- Marine Cable Glands
- Electric Cable Glands
- Fire-Stop Cable Glands
Electromagnetic Compatibility Cable Glands
EMC glands protect cables and machines from electromagnetic interference (EMI), which can compromise the functionality of electrical equipment. Using an EMC gland creates a barrier against EMI at the termination point. They are commonly used in telecommunications applications and situations where EMI can disrupt machine operations.
Marine Cable Glands
The marine industry often requires waterproof cable glands for equipment used underwater or in damp environments. These glands form a watertight seal at the termination point where the cable connects to an enclosure. The assembly includes components that connect on both sides of the enclosure during assembly. Marine cable glands are also commonly used in wastewater treatment facilities.
Electric Cable Glands
Electric cable glands are metal devices that feature an earthing clamp or tag. The earthing component prevents electrocution by redirecting the electrical current to the ground through the wire. It also protects the connection in the event of a short circuit.
Fire-Stop Cable Glands
Fire-stop cable glands are designed to resist fires and explosions. They reduce the spread of fire and smoke while maintaining the electrical connection. These glands are commonly used in the rail industry to protect passengers, personnel, and goods on board a train.
Cable Gland Designations
Cable glands are often given specific designations according to BS 6121. This British Standard provides a system for categorizing cable strain reliefs, specifying their requirements and design features. Although not the most current standard in the EU, BS 6121 designations are still widely used among manufacturers to communicate gland types and their key features. Here are some common types and designations:
1. Type A Cable Glands
Type A glands, also known as “stuffing glands,” are commonly used on unarmored plastic or rubber-sheathed cables. There are four types:
- Type A1: Plastic glands used to protect the cable’s outer jacket.
- Type A2: Plastic or brass glands with an IP68-designated seal between the cable’s outer jacket and the gland.
- Type A3: A variation of the type A1 gland with an electrical bond for the inner cable jacket.
- Type A4: A variation of the type A2 gland with an electrical bond for the inner cable jacket.
Type A glands are typically used in both indoor and outdoor applications that do not require armored cables.
2. Type B Cable Glands
Type B cable glands are designed for use with single-wire armored cables with plastic or rubber sheaths. Made of brass, these glands secure the cable’s armor and provide an electrical path between the armor and the gland. They are suitable for indoor applications with low moisture exposure.
3. Type C Cable Glands
Type C cable glands are intended for use with plastic or rubber-sheathed cables with armor or braiding. Made of brass or stainless steel, these glands serve a similar purpose as type B cable glands. The primary difference is that type C glands feature an IP68-designated seal between the outer sheath and the gland, providing additional protection against moisture and environmental exposure. They are suitable for outdoor applications with a higher need for weatherproofing and waterproofing.
4. Type D Cable Glands
Type D cable glands are designed for use with armored or wire-braided lines featuring plastic or rubber outer sheaths. The key difference between type D and type B glands is the IP68-seal between the inner sheath and the threaded fixing part.
There are two variations of type D glands:
- Type D1: The basic version with an IP68 seal between the inner sheath and the fixing component.
- Type D2: This variation also has an electrical bond for the inner sheath of the cable.
5. Type E Cable Glands
Type E cable glands are used on cables with armor or braiding and plastic or rubber outer sheaths. They are typically made of brass or stainless steel. Similar to type C cable glands, type E glands feature an armor locking ring and inner and outer seals rated to IP68. The outer seal grips the cable sheath, while the inner seal grips the cable’s bedding layer.
There are two variations of type E glands:
- Type E1: Has all the basic features of the type E gland.
- Type E2: This variation includes an electrical bond for the inner sheath of the cable.
Type E cable glands are suitable for applications exposed to the elements due to their excellent waterproofing and weatherproofing capabilities.
6. BS 6121 Suffixes
Cable glands with B, C, D, and E designations often feature a suffix indicating the specific armoring they are designed for:
- W: Single-wire armored cables
- T: Pliable wire armored cables
- X: Wire-braided cables
- Y: Aluminum strip armored cables
- Z: Double steel tape armored cables
The cable gland’s designation will include the cable type first, followed by the protection suitability. For example, a type C cable gland designed for a single-wire armored cable will have a designation of “CW.” If a gland design can be used for multiple armoring variations, all relevant suffixes will be added after the cable gland type. For example, a type B cable gland designed for both single and pliable wire armored cables will have a designation of “BWT.”
How to Choose a Cable Gland
With numerous cable gland options available, it can be challenging to determine the right one for your specific application. To make an informed choice, consider the following questions:
- What is the nature of the installation – domestic, commercial, or industrial?
- Will the cable gland be used in an indoor or outdoor environment?
- What are the temperature conditions, and how much will they fluctuate?
- Will the cable gland be exposed to moisture, dust, dirt, or corrosive elements?
- Are there any risk factors, such as an explosive or corrosive atmosphere?
- What is the cable size, and is it armored? If armored, what type of armor does it have?
Once you have answered these questions, you can narrow down your options and make a final decision based on cost.
Shop Cable Glands From AerosUSA, Inc.
Cable glands are essential in almost every industry, including aerospace, marine, power, telecom, and industrial sectors. These glands ensure safety and reliable connections. At AerosUSA, we specialize in wire and cable protection systems. Our products, manufactured by Flexa GmbH, include cable covers, shielding systems, and high-quality cable glands. With our diverse selection and industry experience, we can provide solutions tailored to your specific needs. We offer quick responses, competitive pricing, and fast turnaround times.
Contact AerosUSA today to learn more about our cable glands and explore our wide range of options.
