Heat-shrinkable sleeves and tubing are commonly used insulating protective materials for cables. The primary material for these products is polyethylene (PE), which is made heat-shrinkable through two processes: radiation cross-linking and heating expansion. The shrinkage ratio is approximately 3:1, and available sizes range from 50mm to 350mm.
They can serve as heat-shrinkable inner protective sleeves, outer jackets, and waterproof insulating sleeves in cable accessories. Based on common classifications, these sleeves are generally divided into standard wall sleeves and medium-wall sleeves.
Characteristics: Irradiated cross-linked heat-shrinkable sleeves are typically used for insulating protection in medium and low-voltage power products and for waterproofing in communication products. The inner wall of the product is coated with a spiral pattern or is fully coated with a high-performance hot-melt adhesive, providing an effective seal after shrinking.
Basic Information about Heat-Shrinkable Cable Sleeves:
Shrinkage Ratio: ≥ 2:1
Shrinking Speed: Rapid
Common Color: Black (most common)
Inner Adhesive Application: Spiral pattern or full coating
Operating Temperature Range: -55℃ to +105℃
Minimum Initial Shrink Temperature: 80℃
Minimum Full Shrink Temperature: 120℃
Differences Between Medium-Wall Sleeves and Standard Wall Sleeves:
Wall Thickness: The key difference lies in the wall thickness. Heat-shrinkable medium-wall sleeves have a medium thickness, which is slightly thinner than standard wall sleeves.
Adhesive and Application:
Medium-wall sleeves use hot-melt adhesive. They are spiral-coated for sizes up to 75mm (approx.) and can be spiral or potentially fully coated for larger sizes. Externally, the difference is clear, and they are often fully machine-coated products.
Standard wall sleeves typically have manual adhesive application at both ends, though they can also be fully coated. The adhesive layer is often a cold glue, and its waterproof function is generally not as good as that of medium-wall sleeves.
Maximum Diameter & Manufacturing: Due to the different adhesive application methods, the maximum diameter for heat-shrinkable medium-wall sleeves is typically around 200mm, while standard wall sleeves can reach up to 300mm. This is primarily because the equipment for spiral coating large-diameter medium-wall tubes is relatively expensive.
