Hydrogen fluoride (HF) is a chemical widely used in many industries. As a colourless gas or liquid, this compound is a source of the fluorine used in many industrial processes. It is also available as an aqueous solution known as hydrofluoric acid (HFaq).
Hydrogen fluoride is used as a feedstock to produce other compounds, including pharmaceuticals and polymers. It is also widely used in the petrochemical industry as a catalyst.
As a compound, hydrogen fluoride gas is an extremely toxic, corrosive and dangerous gas that can damage lungs and eyes. Hydrofluoric acid is a contact poison and is capable of dissolving many materials, including glass. For these reasons, gaskets for hydrogen fluoride service must be capable of withstanding the aggressive chemical attack of this compound and prevent fugitive emissions from escaping into the surrounding environment.
Given the high toxicity of hydrogen fluoride, the US EPA requires the immediate reporting of any leaks – even a minor leak can result in a plant shutdown, entailing significant downtime and costs.
Gaskets for hydrogen fluoride service from CRG
For industrial processes using hydrogen fluoride, gaskets supplied by CRG and made from Teadit 24SH PTFE sheet are a preferred choice. These gaskets provide superior sealing performance in applications involving aggressive media, including hydrogen fluoride.
24SH gasket material is manufactured by expanding 100% virgin PTFE using a proprietary process that produces a uniform and highly fibrillated microstructure with equal tensile strength in all directions. The resulting material exhibits characteristics significantly different than conventional PTFE sheet.
Compared to regular PTFE gasket material, 24SH sheet is much softer and more flexible, meaning that gaskets cut from this material have superior conformability to flange surfaces which are irregular and rough. In addition, gaskets cut from 24SH sheet are easier to compress and minimize creep and cold flow. Gaskets made from 24SH sheet will seal all aggressive chemicals over the entire 0-14 pH range, except for molten alkali metals and elemental fluorine at high temperature and pressure.
24SH sheet complies to FDA regulations for food contact and EU 1935/2004. Made from 100% virgin PTFE, this sheet only resists chemical attack, but it will not contaminate or discolor end products.
Gaskets cut from 24SH sheet are dimensionally stable (i.e., they do not get wider when compressed) and have exceptional mechanical strength which allows operation with minimal creep at elevated temperatures. These gaskets are suitable for use on all types of flanges and nearly all media, with a wide service temperature range, and are especially appropriate for applications with the toughest demands on purity.
To find out more about the gaskets for hydrogen fluoride service which CRG can supply, please contact our sales team at crg@canadarubbergroup.com.