Secondary Metallic Wiper Seal – Internal & External Roofs

The DirectFlex Secondary metallic wiper seal is a specialized type of seal that is used in storage tanks with both internal and external floating roofs. This seal is designed to provide an additional layer of protection against the escape of vapors and liquids.

The secondary metallic wiper seal consists of a series of metal plates that are attached to the underside of the floating roof. The plates are positioned against the tank wall and create a tight seal that prevents the escape of vapors. The shoe wiper is designed to move across the tank wall, wiping away any liquid that may have accumulated on the roof surface. This helps to prevent the liquid from seeping into the primary mechanical shoe seal or other shoe seals and compromising their effectiveness.

The secondary metallic wiper seal is particularly useful in tanks with external floating roofs. Where external factors like wind can cause the roof to shift and move. The Secondary wiper seal helps to ensure that the floating roof remains in constant contact with the tank wall. Creating a secure seal that minimizes the risk of vapor emissions and spills. In tanks with internal floating roofs, the secondary metallic wiper seal can help to prevent the accumulation of liquids on the roof surface. Which can compromise the effectiveness of other seals.

The DirectFlex Secondary Metallic Wiper Seal is manufactured under the guidance of DirecTank’s Exhaustive QA/QC program and ISO accreditation. Every seal is subjected to a thorough engineering analysis and validation process.


Key Features

  • Unmatched sealing performance ensuring tight fit against the tank shell with virtually zero gapping
  • Hardened high-tensile stainless-steel support plates providing continuous, reliable ‘spring-back’ over the long service life for all operational and tank shell conditions
  • Can be installed in or out-of-service
  • Support plates are lapped and independent, so they are not connected to one another, enabling sufficient degree of freedom for variable rim space and inherent flexibility
  • Continuous vapor barrier fabric on the underside, so no need for unreliable gaskets on the support plates
  • Premium vapor barrier fabric options, including polyurethane and Teflon
  • Wiper tip is bolted in-place, so no need for installing time-consuming rivets.
  • Protector Clips on the underside to shield the wiper tip fasteners from contacting the tank shell
  • Can be designed and equipped with burn-out ports for fire-fighting foam systems.

Key Benefits

  • Robust, customized components developed to provide continuous, worry-free operation
  • Wiper tip is highly resilient and chemically compatible and designed to function in almost all conditions, maintaining a tight fit on even tank shells in poor condition with abnormalities and obstructions.
  • Excellent support plate Compression ensuring a tight fit across entire working range
  • Premium, independently certified materials with full traceability
  • Simple, Safe Installation with all-bolted connections, no necessary hot-work, and no gasketed connection between the support plates
  • Suitable for a broad range of service conditions, tank shell conditions, stored products, and floating roof types.
The DirecTank DirectFlex Secondary Metallic Wiper Seal for External Floating Roofs

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