The outer sheath is a critical component for the integrity and longevity of a cable, acting as the first line of defense against physical and environmental aggressions. It protects the internal components against extreme temperature variations, exposure to oils and chemicals, hydrostatic pressure, UV radiation, saline moisture, and abrasive mud.

The norm NEK TS 606:2016 It is the reference for low and high voltage cables in offshore installations, and defines stringent requirements for sheathing materials, classifying them mainly into two types: SHF1 e SHF2.

Technical Definitions

• SHF1 (Sheath, Halogen-Free, Thermoplastic): A halogen-free thermoplastic compound with low smoke and toxic gas emissions in case of fire (LSZH – Low Smoke Zero Halogen). Being a thermoplastic, it softens when heated and hardens when cooled, without chemical alteration.
• SHF2 (Sheath, Halogen-Free, Cross-linked Thermoset): A cross-linked thermoset (or elastomeric) compound, also halogen-free and with LSZH characteristics. The cross-linking process creates permanent chemical bonds, giving the material superior thermal stability and greater resistance to aggressive fluids and deformation under heat.

Key Differences and Strategic Applications

The choice between SHF1 and SHF2 is determined by the requirements of the application and the installation environment.

• SHF1: It is characterized by its greater hardness and rigidity. It is the ideal choice for controlled indoor environments where human safety and the protection of electronic equipment are priorities.
  • Typical Applications: Data centers, control rooms, high-density commercial buildings (hotels, hospitals), and public transportation systems such as subways.
• SHF2: It stands out for its superior flexibility, robustness, and resistance to harsh environments. Its thermosetting nature makes it resilient to oils, mud, chemicals, and temperature variations.
  • Typical Applications: Oil and gas platforms (offshore), vessels, shipyards, and industrial environments exposed to inclement weather and hydrocarbon contamination.

Comparative Analysis of Properties (According to IEC Standards)

The table below details the performance differences between the compounds, according to the tests required by the IEC standards, which serve as the basis for NEK 606.

Looking for cables with this specification? Check out our products:

1. Maritimus® Line (IEC 60092 Standard)

The standard choice for commercial and naval vessels. This line strictly adheres to the series standards. IEC 60092, ensuring safety and performance in fixed onboard installations.

• Applications: Lighting, control, instrumentation and general power on ships.

• Highlights: Fire-resistant (IEC 60331) and flame-retardant options.

• Available Models: Instrumentation, Power and Control Cables (Fire Resistant and Flame Retardant), as well as Medium Voltage options.

👉 [Access the Maritimus® Line Technical Catalog here.]

2. Deepsea® Line (Offshore / NEK-606 SHF2)

Designed for the most aggressive conditions of the offshore and oil & gas industry. These cables have a protective covering. SHF2, offering superior protection against Mud (Mud Resistant), oils and mechanical abrasion.

• Applications: Oil platforms, FPSOs, areas with hydrocarbon deposits, and drilling mud.

• Highlights: Extreme chemical and mechanical resistance (SHF2).

• Available Models: Instrumentation, Medium Voltage and Power Cables (all with SHF2 mud protection).

👉 [Access the Deepsea® Product Line Technical Catalog here.]

3. Hydrocore® Line (Subsea / Polyurethane PUR)

The high-performance mechanical line. Manufactured with a coating in Polyurethane (PUR)These cables offer maximum resistance to tearing, cutting, and hydrolysis, making them ideal for humid and dynamic environments.

• Applications: Deck equipment, naval robotics, and areas subject to high mechanical stress and constant humidity.

• Highlights: Polyurethane (PUR) ensures superior durability in dynamic (mobile use) and submerged environments.

• Available Models: Instrumentation and Power/Control (Fire Resistant and Flame Retardant with PUR sheath).

👉 [Access the Hydrocore® Product Line Technical Catalog here.]

Frequently Asked Questions about NEK 606 Covers (SHF1 and SHF2)

Question 1: What does the acronym SHF1 mean? Resposta: SHF1 stands for "Sheath Halogen Free 1". It is a halogen-free thermoplastic compound, required by the NEK 606 standard for cables installed in internal areas of vessels and platforms. Its main function is to ensure safety: in case of fire, it does not emit toxic or corrosive gases or dense smoke.

Question 2: Can I use SHF1 cable outdoors (on deck)? Resposta: Although the SHF1 has UV resistance, for harsh outdoor areas in offshore environments, the SHF2 It is the most suitable. SHF2 is a cross-linked material (harder and more resistant) that better withstands the attack of oils, greases, and the mechanical abrasion typical of the deck.

Question 3: Is the SHF1 cable mud resistant? Resposta: Generally not. Resistance to drilling mud (Mud Resistant) is a typical characteristic of the compounds. SHF2If your project requires a "Mud Resistant" specification according to NEK 606, you should choose cables from our line. Deepsea (SHF2).