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External & Internal Floating Roof Seal

  • External & Internal Floating Roof Seal

Storagetech™ seal systems are designed to prevent product loss and atmospheric contamination from Aboveground Storage Tanks as well as provide a weather shield. Seal systems meet or exceed environmental regulations and are custom designed to ensure effective operation in specific tank conditions. ERGIL Storagetech™ seal Systems can be installed while the tank is in-service. It is easy to install and no need for special tool.

API test programs for evaporative loss and emission show that emission from roof (deck) fittings without seals or gaskets can be a significant portion of the total emissions from ASTs. A well-designed and maintained peripheral rim seal may not always keep the tank in compliance. Wind factors can increase VOC emissions, particularly from roof fittings that are not properly sealed.

ERGIL Storagetech™ seal systems are engineered, tested and manufactured to meet EPA-AST Environmental Compliance requirements. Different types of seals & combinations are available to suit pontoon & double deck external floating roof tanks & fixed roof tanks with pan deck roofs or aluminium decks.



ERGIL Storagetech™ offers following Mechanical Seal choices for the safe protection of your Internal floating roof tanks: Primary Shoe Seal Plates

Design Features

Each seal is customized to fit to the tank to ensure maximum performance, long life and safe operation. Primary seals include a variety of configuration and component options.  The shoe is connected by braces to the floating deck and is held tightly against the wall by springs or weighted levers A flexible coated fabric (made by Teflon) is suspended from the shoe seal to the floating deck to form a vapor barrier over the annular space between the deck and the primary seal.  

ERGIL Storagetech™ Primary shoe seals can be categorized as PANTOGRAPH and SCISSOR type seals. The most important issue that affects the performance of the sealing system is that the load which is applied on to the shoe seals needs to balanced and this force covers all openings through rim. Mechanical seal systems are restricted for the lined storage tanks for not damaging the cladding material.  

Pantograph Type

Thanks to the pressure applied by the weights, the pressure on the top and bottom of the mechanical seal is maximized. Because of its weighted construction, Because the materials used are thinner than Carbon steel and Aluminum as well as the usage of additional weight is not required, the system minimizes product escape with the effective pressure provided by the springs, unlike the weighted system. Effective seal performance can cover openings up to 200 mm. and it can work with ±100 mm tolerance. 

Scissor Type ( Shoe Type)

The most important case in usage of this type sealing is to increase the material strength by reducing the weight and to ensure the sealing of especially light and corrosive storage products.  

ERGIL recommends the use of Scissor type also called shoe type sealing in lieu of pantograph seal in order to balance price / performance ratio for extreme corrosive volatile or light storage products. Effective seal performance can cover opening up to 200 mm. And it can work out with ±100 mm tolerance. Thanks to its superior spring system, it successfully meets 300 mm rim width and works effectively maximum ±100 mm tolerance in range. 

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