DuPont Kalrez - Seals for approval

The production of pharmaceuticals demands that the highest standards of safety, hygiene and quality control are reached as efficiently and cost-effectively as possible. DuPont™ Kalrez® perfluoroelastomer parts offer best-in-class high-performance seals to help meet these needs.

The regulations safeguarding pharmaceutical product safety are, by necessity, extremely strict. Kalrez parts for harmaceutical applications offer the requisite cleanliness and chemical inertness with the resilience of a true elastomer. With a combination of thermal and chemical resistance, and rubber-like sealing ability, Kalrez parts offer a new level of protection against contamination and seal failure, while meeting stringent FDA and pharmacopeia regulations for purity and cleanliness. These characteristics are vital for the pharmaceutical production process, which often involves aggressive chemicals and high temperatures. High-performance seals ensure safety and hygiene, and help avoid contamination.

The DuPont Kalrez product line, dedicated to life sciences, has been specifically designed to deliver outstanding performance in aggressive process environments. Kalrez parts offer optimal seal performance and resistance to acids, amines, ultrapure deionised water, strong bases and high temperatures for cleaning in place (CIP) and sterilisation in place (SIP).

DuPont Kalrez parts last longer and seal more effectively than other elastomers in demanding processing environments. These perfluoroelastomer parts (FFKM) resist more than 1,800 different chemicals, while offering the high-temperature stability of PTFE (327°C). The proven long-term performance of Kalrez parts can mean less-frequent seal changes, repairs and inspections, increasing process and equipment uptime for greater productivity and yield.

Sanitary seals

The latest offering from DuPont, Kalrez LS390, is a perfluoroelastomer part ideal for use as sanitary seals in pharmaceutical applications where US FDA, USP Class VI at 121°C and Japanese pharmacopoeia compliance is required.

Typical problems experienced in sanitary seal applications are usually related to thermal and chemical resistance challenges, compression set (permanent deformation) and high static friction (stiction). These factors can cause intrusion in the production line or dead space, which increases the risk of contamination or leakage unless seals are continually tightened.

Kalrez LS390 has been designed to address these issues by offering high hardness properties, low stiction, and broad chemical and temperature resistance (up to 220°C (428°F). These properties enable increased mean time between repair.

Improvement in action

Kalrez LS390 has successfully been used in a Japanese infusion-drop product operation that used pure-steam SIP. In this instance, the manufacturer chose Kalrez LS390 because of the improved chemical resistance and lowered stiction performance.

The company had previously experienced problems with its existing material (silicone rubber seals), which had issues with steam resistance, high stiction and a maintenance period of six months. After switching to Kalrez LS390, the performance improvements were substantial. Kalrez LS390 sanitary seals provided excellent resistance to chemicals and pure-steam SIP. The sanitary seals lasted a year without any damage on the contacting surface, which increased productivity, lowered maintenance costs and minimised unscheduled downtime, resulting in a lower total cost of ownership.

Kalrez LS390 sanitary seals' low stiction properties and high hardness make these parts an excellent choice for sanitary-seal applications. The properties also facilitate sanitary-seal piping disassembly. With their unique grey colour, LS390 parts are easy to identify for proper material selection and application. A maximum application temperature of 220°C (428°F) is suggested.

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