Description

Heat-shrink tape is a type of heat-recoverable (heat-shrinking) wrap tape made to shrink and form a tight, protective layer when heat is applied. When heated with a heat gun or torch, it shrinks and seals around cables, connectors or components, creating insulation, environmental protection, and mechanical support. It’s especially useful where traditional heat-shrink tubing can’t slide over a part, such as complex shapes or installed harnesses.

Raychem heat shrink tapes, such as the HVBT (medium voltage) and RT-555 (high-temperature), are specialized, adhesive-coated, or self-amalgamating materials designed for sealing, insulating, and protecting electrical components. They offer excellent environmental sealing, high-temperature resistance (up to 200° C for RT-555), and are ideal for complex shapes, repairs, and harsh, high-vibration, or oil-exposed environments.

Key Features

• Heat-recoverable: Shrinks a set percentage when heated to high temperature (often > +200 °C).
• Bi-layer design: Some products (like RT-555) have a fluoropolymer adhesive layer that melts to create a tight seal.
• Wrap-around form: Allows installation without disconnecting or disassembling cables.
• Fluid resistant & high temp tolerant: Many are designed for harsh environments (e.g., aerospace, offshore, industrial).

Material & Performance: Primarily made from polyolefin or specialized, high-temperature, fluid-resistant materials (e.g., ETFE), they offer high tensile strength and chemical resistance.

• Maximum continuous temperature: ~+200 °C.
• Minimum shrink recovery: ~35 % of stretched length.
• Peel strength: ≥10 lbs per inch of width — ensures strong adhesion after shrink.
• Sealing pressure resistance: Up to ~15 psi.

Key Applications

• Insulation & Sealing: Used on busbars, connectors, and cable harnesses to protect against moisture, dust, and electrical discharge.
• Repair & Maintenance: Allows for field repairs of cable jackets without disconnecting components.
• Industrial Environments: Suitable for mining (Group I) and surface (Group II) industries, particularly in explosive or high-vibration areas.

Types

• HVBT (Heat Shrink Busbar Tape): Ideal for medium voltage (up to 15-25 kV) busbars, these tapes shrink by 30% and feature an adhesive layer that seals upon heating.
• RT-555 High-Temperature Tape: A two-layer, wrap-around tape designed for aerospace and defence, resisting temperatures up to 200° C and harsh fluids.
• Self-Amalgamating Tapes (e.g., MVFT): These provide instant insulation enhancement and seal without heat, often used for, but not limited to, quick repairs.

Installation Tips

• Heat Application: A hot air gun is used to shrink the tape, typically requiring temperatures over 200°C for specialized tapes like RT-555, the adhesive flows to bond layers together sealing the assembly.
• Application Method: Wrapped around the component, often with an overlap to ensure a secure, sealed, and insulated finish.
• Safety: Always apply in a well-ventilated area and use eye protection, as the adhesive can be very hot.