Why Hoonsun Is Your Best Choice for Cable Glands?

During cable laying, it’s often impossible to install the entire length in one go. In these cases, two sections of cable need to be connected at a cable gland. A cable gland is the connection point between two cables and is critical for both electrical performance and mechanical protection.

From the installation position, cable glands can be divided into intermediate glands (installed in the middle of the cable route) and end glands (installed at the termination of the cable). In addition to providing a reliable electrical connection, a high-quality cable gland must also offer mechanical strength, insulation performance, waterproofing, dustproofing, and vibration resistance, ensuring long-term safe and stable operation of the cable system.

What Are The Working Principle Of a Cable Gland?

Cable glands serve far more than simply “connecting two conductors.” Their primary function is to ensure that the electrical performance at the gland, including conductor connection, electric field distribution, insulation restoration, and shielding/sheath restoration, is highly consistent with the original cable structure.

By precisely reconstructing these critical elements, well-designed cable glands help maintain the overall reliability, safety, and long-term stability of the cable.

What Are the Main Cable Gland Structure Types?

A cable gland is made up of several key structural parts. Each part plays a different role in maintaining electrical performance, mechanical strength, and environmental protection at the gland.

1. Conductor Connection

The conductors (copper or aluminum) of the two cable sections must be reliably connected to ensure:

• Low contact resistance
• Stable current-carrying capacity
• Good long-term electrical contact
• Common conductor connection methods include crimping, welding, and bolted connections.

If the contact is poor, it can cause localized overheating, increased resistance, and eventually gland failure.

2. Insulation and Electric Field Restoration

Beyond the conductor, a cable contains insulation layers, semiconductive shielding layers, metallic shielding/armor, and an outer sheath. At the gland, these structures must be reconstructed as closely as possible to the original cable design to:

• Maintain insulation performance
• Ensure uniform electric field distribution along the cable
• Poor restoration,such as air gaps, uneven insulation thickness, or discontinuous shielding.It can cause electric field concentration, leading to partial discharge, insulation aging, or even breakdown.

3. Outer Sheath, Shielding, and Armor Restoration

For high-voltage or armored cables, the metallic shielding and armor layers are crucial.

They provide:

• Mechanical protection against impact and compression
• Electromagnetic shielding reduces interference
• Grounding and fault current return paths

At the gland, these layers must be reconnected and restored to avoid additional electrical and safety risks.

The outer sheath also needs to be:

• Waterproof and dustproof
• Corrosion-resistant
• Resistant to UV, chemicals, and environmental aging

This ensures long-term reliability of the cable gland in harsh environments.

4. Mechanical Fixing and Waterproof Sealing

Cable glands usually incorporate specialised accessories or junction boxes, which may include:

• Sealing materials and waterproof gaskets
• Cable glands, heat shrink or cold shrink tubing
• Mechanical clamping and strain relief components

These structures:

• Securely fix the cable in place, preventing tension, bending, or vibration from being transmitted to the core gland
• Provide effective waterproof and dustproof sealing, blocking moisture and contaminants from entering

Improve overall mechanical stability and extend the service life of the gland

How To Install Cable Glands?

Power Off and Isolate the System

Switch off the power supply and disconnect all relevant equipment to ensure electrical safety before any work begins.

Strip the Cable Jacket

Strip the outer sheath of the cable to a suitable length, exposing the armor, shielding layer, and inner sheath as required. Then carefully remove the inner sheath to expose the conductor according to the gland design specifications.

Prepare Conductors and Insulation

Clean the conductors, shielding layer, and insulation surfaces to ensure they are free of oil, moisture, and mechanical damage. Where required, use approved crimping or soldering methods to complete the conductor connections and ensure low contact resistance.

Rebuild Insulation and Electric Field Control

Install stress cones, stress control tubes, and the necessary heat-shrink or cold-shrink components to restore the original insulation structure. Perform interface treatment (e.g., applying silicone grease) to eliminate air gaps and avoid localized electric field concentration.

Install Sealing and Outer Protection

Fit the waterproof seals, sealing grommets, and outer casing or gland fasteners. Restore the outer sheath and complete the mechanical fixing so the cable is securely clamped and protected against tension, bending, and vibration.

Final Inspection and Commissioning

Check that all layers of the cable gland have been properly repaired, that the continuity of the shielding and armor layers remains good, and that the grounding is reliable. After the inspection is passed, restart the system and monitor the cable gland’s operation during initial operation.

How To Use Cable Glands To Prevent Cable Faults?

Properly designed and installed cable glands are critical to preventing power cable faults. Their role goes far beyond a simple connection. They directly affect the electric field distribution, insulation reliability, and long-term stability of the entire cable system.

Control the Electric Field and Restore Insulation Correctly

Even slight negligence in electric field control, insulation reinstatement, or shielding restoration can create a non-uniform electric field, leading to partial discharge and, over time, insulation breakdown. Research shows that in many cable systems, the intermediate gland is the most vulnerable unit, with over 70% of failures caused by gland defects or partial discharge at the gland.

Address Environmental and Process-Related Risks

Cable glands are often installed under complex site conditions. Factors such as complicated manufacturing/installation processes, poor on-site environment, incorrect or incompatible materials, inadequate sealing, moisture ingress, and improper armor or shield grounding all significantly increase the risk of joint failure and accelerate aging.

Strengthen Quality Across the Entire Joint Lifecycle

To effectively prevent cable faults, high-quality materials must be used, the manufacturing process strictly controlled, and the professional installation of cable galnds ensured. Equally important is a comprehensive inspection and testing after installation to confirm that the joint structure, shielding, sealing, and grounding have been correctly restored.

Only by strictly controlling every step from material selection and jointing techniques to final testing can the safety, reliability, and service life of the cable system be truly guaranteed.

Why is The Importance Of Cable glands cannot Be Ignored?

• Poor Cable gland performance, improper insulation restoration, or inadequate sealing often make them vulnerable points for failure in cable lines.
• In high-voltage or harsh environments, uneven electric field distribution, interruptions in shielding or armoring, and excessive mechanical stress can all accelerate failures due to improper cable glanddesign/construction.

Correctly designed/installed cable gland can make cable systems more durable, safe, and stable in operation.

What Types Of Cable Glands Do We Manufacture?

Metal cable gland

Metal cable glands are metal contacts or metal shielding/armor repair components used to connect two or more cable segments. They ensure electrical continuity of the conductor connection, integrity of the shielding/armor, water resistance, dust resistance, and improve mechanical strength and electromagnetic compatibility.

Nylon Cable Gland

A nylon cable gland is a cable seal primarily made of nylon. It is constructed from PA material, offering high tensile strength, good toughness, and excellent waterproof performance.

It is mainly used for securing and sealing unarmored/plain cables, and is not a traditional cable gland specifically designed for splicing cable conductors.

Stainless Steel Cable Gland

A “stainless steel cable gland” is a mechanical device used to safely and reliably introduce cables into electrical equipment or enclosures.

What Is the Internal Structure of Our Cable Glands?

A typical power cable gland (cable gland joint) is designed with several internal functional parts that work together to ensure electrical reliability, mechanical strength, and environmental protection. Its internal structure can generally be divided into the following key sections:

1. Conductor Joint

At the core of the joint, the metal conductors (such as copper or aluminum) of the two cable sections are connected together by methods like crimping, bolting, or welding. This part ensures continuous current flow and low contact resistance, effectively reducing heat generation, power loss, and the risk of local overheating at the joint.

2. Insulation Reinstatement

Around the conductor, the original cable uses an insulation layer (e.g., XLPE, EPR). At the joint, this insulation must be removed, rebuilt, and restored. This typically involves stripping the original insulation to a specified length, cleaning the surface, and then installing stress-control cones (stress cones), heat-shrink or cold-shrink tubes, and insulating sleeves. The purpose is to maintain insulation performance, keep the electric field distribution uniform, and prevent localized insulation damage or partial discharge.

3. Shield / Screen / Semi-Conductive Layer Reinstatement

For medium- and high-voltage cables, the conductor and insulation are usually surrounded by semi-conductive inner and outer shields, metallic shielding (tape or wire), and sometimes armor. At the joint, these layers are reconstructed and reconnected using copper or aluminum tape shields, copper mesh, steel tape/wire armor, and grounding glands. This section helps maintain a uniform electric field, reduce electromagnetic interference (EMI), provide mechanical protection, and form a reliable grounding path for fault currents.

4. Armour and Outer Sheath Reinstatement

If the cable has metallic armor (such as steel tape or wire) or a metallic sheath, the armor or sheath is restored and electrically connected at the joint, often with dedicated grounding/armor cable glands. The outer sheath (usually a plastic or rubber jacket) is then reinstated to cover the entire joint area. This layer provides mechanical protection, waterproofing and moisture resistance, and shields the internal structure from external impacts, chemicals, and corrosion.

5. Sealing, Moisture Barrier, and Mechanical Fixing

Cable glands are particularly vulnerable to moisture and contaminants, so an effective sealing and fixing system is critical. Inside the joint, sealing resins (such as epoxy or polyurethane), sealing gaskets, heat-shrink or cold-shrink kits, waterproof adhesives, and sealed housings are used to block moisture ingress and protect insulation and shielding layers from degradation and corrosion. At the same time, tension sleeves, clamps, stress cones, and fixing bolts provide mechanical fixing and strain relief, preventing tension, bending, and vibration from being directly transmitted to the conductor connection, thus maintaining structural stability and avoiding loosening or damage under mechanical stress.

What Are the Application Scenarios For Hoonsun Cable Glands?

Hoonsun cable glands are widely used in indoor/building power distribution, underground and tunnel/urban infrastructure, medium- and high-voltage transmission and distribution systems, as well as renewable energy, offshore, and other special environments.

In these scenarios, cable glands help provide reliable sealing, strain relief, and mechanical protection while adapting to different requirements in terms of environmental conditions, voltage level, mechanical stress, waterproof performance, and corrosion resistance. By selecting the appropriate Hoonsun cable gland for each application, users can significantly enhance the safety, durability, and overall reliability of their cable systems.

What Are Hoonsun’s Cable Gland Solutions?

Hoonsun offers metal cable glands made from materials such as nickel-plated brass or stainless steel, combined with nylon clamps and modified rubber sealing elements, achieving high mechanical strength and excellent corrosion resistance.

Many models offer protection ratings up to IP68 and can even undergo pressure testing, ensuring reliable waterproof and dustproof performance in outdoor, industrial, and harsh environments.

The internal structure of these metal cable glands is carefully designed with clamping claws, O-rings, and lock nuts to ensure the cable is securely held and sealed during operation, preventing the effects of tension, vibration, and thermal expansion and contraction.

When selecting Hoonsun cable glands, users can choose from a variety of thread types and sizes and match them to the cable’s outer diameter and the equipment’s inlet port. The shell thickness, strength, torsional, and tensile properties are carefully designed to meet the needs of heavy-duty applications.

Proper installation ensures that the equipment sidewall or inlet port matches the thread length, the nut is securely tightened, and a continuous seal is formed between the gland and the equipment. This helps to fully utilize the performance of Hoonsun cable glands and significantly improves the safety and reliability of the entire cable system.

How to Choose the Right Hoonsun Cable gland?

Choosing the right Hoonsun cable gland depends primarily on the compatibility with the cable, equipment, and environment. You can focus on the following key factors:

Thread Size and Equipment Bore Diameter

Confirm that the thread specification matches the opening on the equipment panel or housing to ensure proper installation and locking of the gland.

Cable Outer Diameter and Clamping Range

Check the cable’s outer diameter and select a gland with a clamping range that fully covers that diameter. This is crucial for sealing performance and stress relief.

Material, Environment, and Protection Rating

For outdoor, marine, or chemical environments, choose nickel-plated brass or stainless steel for better corrosion resistance.

If you require strong waterproof and dustproof performance, prioritize glands with IP66/IP68 or higher ratings.

Mechanical Stress, Shielding, and Certifications

If the cable is subjected to tensile or vibration stress, consider using reinforced cable glands, locknuts, or shock-absorbing structures. For cables with metal shielding or armor, choose models that support shielding/grounding connections.

In hazardous or explosive environments, ensure the product has the required UL, explosion-proof, or relevant certifications.

Inventory, Installation, and Maintenance

A small number of commonly used cable sizes are available on site for quick replacement. During installation, ensure that the seals are intact, the nuts are properly tightened, and the work area is clean and dry to prevent sand, dust, or moisture from damaging the seals.