Waterproof Forms of Waterproof Cables

Waterproof Forms of Waterproof Cables

• 2024-12-28 15:30:26
• by Admin

Generally, it is divided into longitudinal water-blocking and radial water-blocking. For longitudinal water-blocking, commonly used materials are water-blocking yarns, water-blocking powders, and water-blocking tapes. 

The water-blocking mechanism is that these materials contain a water-expandable material. When water enters from the cable end or through a defect in the sheath, this material will rapidly expand upon contact with water to prevent further diffusion of water along the longitudinal direction of the cable, achieving the purpose of longitudinal waterproofing of the cable. 

Radial water-blocking is mainly achieved by extruding an HDPE non-metallic sheath or through hot-pressing, welding, or cold-drawing a metal sheath.

Differences between Waterproof Cables and Water-Blocking Cables

Waterproof Cables: Prevent water from entering the interior of the cable structure, and adopt structures and materials with waterproof functions.

Water-Blocking Cables: The assessment allows water to enter the interior of the cable, but under specified conditions, it is not allowed to penetrate to the specified length. 

Water-blocking cables are divided into conductor water-blocking and cable core water-blocking. 

Conductor Water-Blocking Structure: During the single-wire stranding process, the water blocking powder and water-blocking yarn are added. 

When the conductor gets wet, the water-blocking powder or water-blocking yarn will expand upon contact with water to prevent water penetration. 

Of course, the solid conductor has better water-blocking performance.

Cable Core Water-Blocking Structure: When the outer Sheath is damaged and water enters, the water-blocking tape will expand upon contact with water. 

After the water-blocking tape expands, a water-blocking section is quickly formed to prevent further water penetration.

For three-core cables, it is quite difficult to achieve overall water-blocking of the cable core because the gaps in the middle of the three-core cable core are large and irregular.

Even if the water-blocking tape is used to fill them all, the water-blocking effect is not good. 

It is recommended that each wire core be produced according of the single-core water-blocking structure and then cabled.

Rubber-sheathed cables also have waterproof properties, but they are not professionally waterproof.

However, all electrical wires and cables have waterproof properties in different senses. 

First of all, not all cables are waterproof. 

Whether a cable is in waterproof or not depends on the laying environment of the cable. Generally speaking, waterproof cables include those laid in inland rivers or on the seafloor. 

Such cables generally have a longitudinal waterproof isolation layer and are usually armored.