In chemically demanding applications, conventional elastomer O-rings quickly reach their limits, as they do not offer the required properties. With encapsulated O-rings made of PFA (perfluoroalkoxy pol-ymers) and FEP (fluorinated ethylene propylene), the poesia group provides solutions for demanding special applications. 

Aggressive media, high temperatures or strict regulatory requirements demand reliable, durable, high-performance and resistant sealing solutions. These are primarily required in applications within the food, pharmaceutical and chemical industries. Encapsulated O-rings provide the ideal solution.

Encapsulated O-rings: Definition

An encapsulated O-ring consists of an elastic core made of silicone or FKM (fluorocarbon rubber, commonly known under the brand name Viton®), which is enclosed by a seamless encapsulation made of PFA or FEP.

Differences between FKM, PFA and FEP

FKM is commonly used as the core material. It is a high-quality synthetic elastomer with resistance to high temperatures (approx. -25 to +200°C).

PFA offers continuous temperature resistance from approx. -200 to +260°C and is particularly suitable for demanding applications involving high temperatures and mechanical stress.

FEP has a continuous temperature resistance from approx. -60 to +200°C and stands out due to its excellent chemical resistance as well as its good cost-performance ratio.

Applications

O-rings with a PFA or FEP encapsulation are particularly suitable for applications in the following industries: chemical industry, food and beverage production, pharmaceutical industry, semiconductor technology, water treatment, as well as paints and coatings industry.

Specifically, encapsulated O-rings are used in pumps, valves, fittings, process systems with aggressive cleaning media (acids, alkalis, solvents), filling, dosing and mixing systems, reactors and laboratory equipment, as well as in slow-moving pistons. Thanks to the fluorinated encapsulation, the O-rings also exhibit very low permeability, making them suitable for applications involving gaseous media.

Compliance with applicable standards

The PFA and FEP encapsulated O-rings from the poesia group are characterised by their FDA compliance. They meet the relevant requirements for use in the food and pharmaceutical industries. In addition, PFA- and FEP-encapsulated O-rings comply with Regulation (EC) No. 1935/2004 for materials intended to come into contact with food, making them ideal for use in sensitive applications.

Wide range of sizes available

The seals are available in a wide variety of sizes (metric and inch sizes) from the poesia group. Typical cross-sections range from 1.50 mm to 31.75 mm. Special cross-sections are available upon request. Industrial diameters and custom shapes can also be supplied.

Delivery times

Most sizes are available from stock at the poesia group, ensuring short delivery times.

Specialists

For all questions regarding PFA and FEP encapsulated O-rings, the specialists of the poesia group are happy to assist.

Ordering

PFA and FEP encapsulated O-rings can be ordered by phone (Tel. +41 44 734 25 10) or by email at This email address is being protected from spambots. You need JavaScript enabled to view it..

The products will soon also be conveniently available via our webshop: https://shop.herzog-dichtungen.ch/de

Our technical specialists will be happy to assist you with orders or de-tailed information.

Key advantages of PFA and FEP encapsulated O-rings

They are resistant to chemicals and cover a wide temperature range. Compared to pure PTFE seals, they exhibit significantly reduced cold flow, ensuring reliable and long-lasting sealing performance.

Thanks to compliance with regulatory requirements (FDA and EC 1935/2004), they are ideally suited for demanding applications. Compared to conventional elastomer O-rings, they offer a significantly longer service life in such environments. Special sizes are available, and thanks to the poesia group's stock, standard sizes can be delivered at short notice.