Description

Elsewedy 3-Core Armored Copper Cable Joint, (95+50) mm², 1 kV

Introduction: Connection Engineering for Large Power Cables

A cable joint is one of the most critical components in an underground distribution network. It is where the continuity of the original cable sheath ends and the joint must rebuild the cable’s protective system. When working witharmored coppercables with large cross-sections such as(95+50) mm²at1 kV, the joint’s role extends beyond carrying current: it must also provide a mechanical and electrical bridge that restores the cable’s protective and earthing path.

Elsewedy heat-shrink joints are designed to protect copper conductors against oxidation while restoring continuity of the steel armor. This makes them suitable for major infrastructure and industrial projects requiring dependable mechanical protection and power continuity under high-current loads.

Chapter One: Engineering Structure and Four-Layer Protection System

Elsewedy joints use advanced radiation-crosslinked polymer technology and consist of technical layers that work together to rebuild the large-section armored cable:

1. Phase Insulation Tubes

The kit consists of four medium-wall polymer tubes: three for95 mm²and one for50 mm². Each tube heat-shrinks separately over a copper conductor after the mechanical connection is completed.

• Technical Function:The tubes provide dielectric strength well above the operating voltage, helping prevent phase-to-phase faults under high-load conditions. They are designed to withstand thermal stresses associated with the high current carried by the 95 mm² conductor, while retaining flexibility through repeated heating and cooling cycles.

2. Armour Continuity Kit

This is a key component for large cable sizes and includes:

• Copper Braids:Heavy, highly conductive braids connect the steel wire/tape armor from both cable ends, maintaining a path capable of carrying fault and short-circuit currents.

• Constant Force Springs:Flexible metallic components maintain consistent pressure between the copper braid and armor layer, helping preserve electrical contact despite vibration and thermal expansion and maintaining the joint earthing and mechanical-protection path.

3. Sealing System

The outer tubes are lined with a dense layer ofactive hot-melt adhesive.

• Operating Principle:When the outer tube is heated, the adhesive melts and flows to fill air gaps and side openings associated with the large 95 mm² conductor diameter. After cooling, it forms a solid bonded layer against the cable sheath, helping block moisture and oxygen that could corrode the copper and increase contact resistance.

4. Outer Protection Sleeve

A large black tube with a heavy wall, designed to withstand demanding mechanical stresses.

• Features:Manufactured from UV- and abrasion-resistant polyolefin, providing a durable replacement for the cable’s outer jacket across the joint area.

Chapter Two: Technical Performance and Strategic Advantages of Armored Copper

Elsewedy joints for (95+50) mm² cables include features intended for long service life in construction environments:

• Compatibility with Large Diameters:A shrink ratio of approximately 3:1 allows the tubing to seal around both the 95 mm² and 50 mm² conductors while minimizing air gaps that can contribute to partial discharge.

• Stable Conductivity of High-Purity Copper:Copper provides stable conductivity for high loads, while the joint protects connection points from moisture-related oxidation that can raise contact resistance.

• Heavy-duty mechanical protection:By restoring armor continuity, the joint area remains better protected against accidental impact, soil pressure, and machinery loads above buried cable routes.

• Direct Burial After Completion:Once the joint has cooled and passed the required checks, it can be backfilled and returned to service, helping reduce network downtime during emergency repairs.

Chapter Three: Joint Applications in Infrastructure and Industrial Sectors

1. Factories and Substations:Joining main armored feeder cables supplying large motors and central switchboards using (95+50) mm² conductors.

2. Hospitals and Commercial Centers:Connecting main power cables where mechanical protection and reliable earthing are important for stable supply to sensitive equipment.

3. Infrastructure and Ports:Suitable for areas requiring high mechanical protection for underground cables, including rocky soil and routes near bodies of water.

4. Water-Treatment Plants:The dual sealing system helps prevent salts and high humidity from reaching the cable core, protecting copper against chemical corrosion.

Chapter Four: Engineering Installation Protocol

Because of the large 95 mm² conductor size, careful installation steps are required:

• Conductor Preparation:Use professional stripping tools to avoid damaging copper strands, then clean the conductor surface with a wire brush.

• Armor Continuity:Ensure constant-force springs secure the copper braid firmly to maintain an earthing path with performance appropriate to the original cable sheath.

• Shrinking Process:Use a gas torch with a gentle flame and heat slowly from the center toward the ends so the hot-melt adhesive flows evenly.

• Testing:Confirm that adhesive has emerged from the tube ends as an indication that the moisture seal has formed correctly before backfilling.