A Flameproof Double Compression Cable Gland (also known as an Explosion-proof Cable Gland) is a critical safety component used in hazardous zones where flammable gases, vapours, or dust may be present. These glands are engineered to prevent internal explosions from spreading outside the enclosure, ensuring maximum protection for personnel, equipment, and industrial installations.

At Volt Metal Industries, we manufacture high-precision brass flameproof double compression cable glands designed for reliable performance in Zone 1, Zone 2, and other high-risk environments. This guide explains how they work, essential components, applications, and how to select the correct size for your project.

What is a Flameproof Double Compression Cable Gland?

A flameproof double compression cable gland is a heavy-duty gland designed for armoured cables. It provides two levels of mechanical compression:

• Inner compression on the inner sheath
• Outer compression on the armour and outer sheath

This dual sealing mechanism ensures:

• Explosion containment
• Enhanced ingress protection
• Superior mechanical strength
• Consistent electrical continuity

These glands are used to safely terminate cables in flameproof enclosures so that if an explosion occurs inside the equipment, it does not propagate outside.

Key Parts of a Flameproof Double Compression Cable Gland:

A typical flameproof double compression cable gland consists of:

1. Gland Body – The main structure that houses sealing and clamping elements. Designed with precise flame paths to prevent explosion transmission.
2. Inner Seal / Compression Ring – Creates the first compression on the inner sheath, forming a gas-tight seal.
3. Armour Clamping Cone & Ring – Provides mechanical retention and electrical continuity for armoured cables.
4. Outer Compression Nut – Applies the second level of compression on the outer sheath for ingress protection.
5. Flameproof Seal (Elastomer / Rubber) – Prevents the passage of explosive gases along the cable route.
6. Check Nut / Lock Nut – Used for panel fixing and additional mechanical stability.
7. Earth Tag (Optional) – Ensures earthing continuity when required.

All parts are precisely machined for perfect flame paths, torque strength, and long-term reliability.

Size Chart for Flameproof Double Compression Cable Gland:

To choose the correct gland size, consider:

• Cable Outer Diameter (OD)
• Inner sheath OD
• Armour type (SWA, STA, braided, tape, etc.)
• Entry thread requirement (Metric / NPT / PG)
• Hazard zone classification
• Temperature and environmental exposure

Note: For export, thread standards (Metric / NPT / PG) are supplied as per destination market requirements.

Why Flameproof Glands Are Necessary:

Industries that handle combustible materials cannot compromise on cable entry safety. Explosion-proof cable glands are essential because they:

• Restrict flame transmission during internal ignition
• Maintain enclosure integrity under pressure
• Provide dust, moisture, and gas sealing
• Ensure cable strain relief in harsh conditions
• Support grounding and bonding in armoured cable systems

Their construction, tolerances, and materials must withstand the intensity of hazardous environments.

Applications of Flameproof Double Compression Cable Glands:

An explosion-proof cable gland is widely used in:

• Oil & Gas plants
• Chemical and petrochemical industries
• Offshore rigs
• Mining areas
• Refineries
• Flammable vapour zones
• Hazardous process plants
• Power generation units

Its robust sealing system makes it suitable for environments exposed to rain, humidity, dust, and fluctuating temperatures.

Installation Tips for Best Performance:

• Always check cable dimensions before selecting a gland.
• Follow the correct tightening torque for inner and outer compression.
• Ensure the flameproof sealing area is free from damage.
• Use shrouds, washers, adapters, and earth tags where required.
• Avoid mixing thread types without approved adapters.
• Never reuse a flameproof gland once removed from a cable.

FAQs:

1. What is the difference between weatherproof and flameproof cable glands? Weatherproof glands provide moisture and dust protection, while flameproof (explosion-proof) glands prevent explosion transmission in hazardous zones.

2. Are flameproof double compression cable glands only for armoured cables? Yes, they are primarily designed for armoured cables due to the two-stage compression mechanism.

3. Can a flameproof cable gland be used in non-hazardous areas? Yes, but it is not always necessary. However, many industries use them for added safety and mechanical strength.

4. Are shrouds necessary for weatherproof installations? Shrouds are optional but recommended for improving resistance to rain, dust, and corrosive environments.

5. Do flameproof double compression glands come with accessories? Yes, accessories like lock nuts, earth tags, and PVC shrouds can be provided based on customer requirements.

6. What material is best for flameproof cable glands? Brass is preferred for strength, machining accuracy, corrosion resistance, and long-term durability – especially for export applications.

7. Do flameproof glands provide ingress protection? Yes. With proper installation, they offer excellent IP sealing against dust, water, chemicals, and gas ingress.

Contact Volt Metal Industries:

Looking for reliable Flameproof double compression cable glands or Explosion-proof cable glands for your industrial or export requirements?
Reach out to Volt Metal Industries for bulk orders, custom sizing, and global supply support:

•  info@voltmetalind.com
•  www.voltmetalind.com
•  +91 9879332240 | +91 8000222233