Kalrez O-Rings

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kalrezDuPont Kalrez® perfluoroelastomer parts are available in a number of different compounds that are formulated to optimize properties to give the best possible performance in various applications. Modification of the finished properties is achieved by use of fillers and other additives.

Typical Physical Properties1

The table below summarizes the basic physical properties of the most commonly used Kalrez® products for the chemical and hydrocarbon processing industries. Descriptions of the key attributes for each product and their general areas of application follow.


Standard Compounds

Kalrez® 6375

A carbon black-filled compound for general use in O-rings, seals, diaphragms and other specialty parts specifically for the chemical process industry. This compound has excellent, broad chemical resistance, good mechanical properties, and outstanding hot-air aging properties. 6375 is well suited for mixed process streams because of its excellent resistance to acids, bases, and amines. In addition, it is the suggested compound for use in hot water steam, ethylene oxide and propylene oxide. A maximum service temperature of 275ºC (525ºF) is recommended.

Kalrez® 7075

A new compound with enhanced physical performance properties including very low compression set (15% O-rings per ASTM D 395B) and improved seal force retention. It is a carbon black filled compound utilizing new and proprietary cure chemistry technology with mechanical properties designed for improving sealing performance in both high temperature environments and temperature cycling situations. 7075 joins the family of Kalrez ® Spectrum ™ products designed for the chemical processing industry. To provide even greater sealing performance in dynamic applications where low friction is required, 7075 O-rings have a glossier finish than other Kalrez ® parts. 7075 was specifically developed to be used as an O-ring or custom-sealing component in the chemical and hydrocarbon industries, with an improved thermal resistance that extends maximum service temperature to 327°C (620°F). Kalrez ® Spectrum ™ 7075 offers the enhanced elastomeric properties outlined above while providing a chemical resistance better than the industry standard set by Kalrez ® 4079.

Kalrez® 4079

A low compression set compound for general-purpose use in O-rings, diaphragms, seals, and other parts used in the process and aircraft industries. It is a carbon black-filled compound with excellent chemical resistance, good mechanical properties, and outstanding hot air aging properties. It exhibits low swell in organic an inorganic acids and aldehydes and has good response to temperature cycling effects. A maximum operating temperature of 316ºC (600ºF) is recommended, with short excursions to higher temperatures possible. This compound is not recommended for use in hot water/steam applications or in contact with certain hot aliphatic amines, ethylene oxide and propylene oxide.

Specialty Compounds

Note: Before ordering Kalrez#174; parts in specialty products, please consult with technical staff to determine properties needed for the application. Specialty products are generally not held in inventory.

Kalrez® Spectrum™ 6380

is a non-black product specifically developed for chemical processes involving hot, aggressive amines. It has also been successfully used in applications involving highly oxidizing chemicals. In addition, it has excellent overall chemical resistance. This cream colored product is easily identifiable when selecting an O-ring material for harsh chemical plant services.

Kalrez® Spectrum™ 7090

is a product for uses requiring higher hardness/higher modulus than more typical applications. Kalrez® Spectrum™ 7090 perfluoroelastomer parts are well suited for both static and dynamic applications as well as specific sealing applications requiring extrusion resistance at high temperatures. These specialty black parts have excellent thermal and mechanical properties, including excellent compression set and seal force retention, resistance to temperature cycling effects, and rapid gas decompression (RGD). Short excursions to higher temperatures may also be possible.

Kalrez® 0090

is a black product with broad chemical resistance combined with high modulus and high hardness. Kalrez® 0090 parts have outstanding resistance to extrusion and rapid gas decompression (RGD). This product has been independently tested and certified by the Materials Engineering Research Laboratory (MERL – UK) to meet NORSOK-M-710 Rev 2 requirements.

Kalrez® Spectrum™ 0040

is a black product specifically designed for low temperature environments where significant chemical resistance is required. Kalrez® Spectrum™ 0040 parts maintain elasticity and seal force at temperatures unattainable by other perfluoroelastomers.

Kalrez® 1050LF

A general-purpose compound for O-rings, seals, and other parts used in chemical process industries. It has good hot water/steam, excellent amine resistance, and enhanced compression set properties. Maximum recommended service temperature of 288ºC (550ºF). Not recommended for use in organic or inorganic acids at high temperatures.

Miscellaneous Industrial Compounds

Kalrez® 1058

A carbon black-filled compound that has been plasticized with a perfluorinated oil. It is the softest, lowest modulus compound available. Generally, it is similar in chemical resistance to Compound 1050LF; it has an upper service temperature of 260ºC (500ºF). Typically used in applications that require how sealing force or high extensibility including liquid chromatography septa, seals/seats for relief valves and tubing. Its shrinkage is greater than other Kalrez compounds; therefore, finished parts may differ from standard specifications.

Kalrez® 3018

A carbon black-filled compound similar to Compound 1050LF, except for higher hardness/modulus. This compound offers the best hot water/steam resistance and the best high pressure extrusion resistance. Generally used in oil field and process industry applications where these properties coupled with good amine and general chemical resistance are required. A maximum service temperature of 220ºC (428ºF) is recommended.

Kalrez® 2035

A carbon black-filled compound that is well suited for selected applications in the finishings equipment, pharmaceutical, semiconductor, and chemical transportation markets. Compound 2035 has excellent chemical resistance exhibiting low swell in organic acids, inorganic acids, esters, ketones, and aldehydes. This compound is suggested for use in the ethylene oxide and propylene oxide applications. It also offers good mechanical properties. A maximum service temperature of 220ºC (428ºF) is recommended.

Kalrez® 2037

A non-black-filled compound that is well suited for selected applications in the pharmaceutical, semiconductor, and other markets that demand high purity elastomers. Compound 2037 has excellent chemical resistance exhibiting low swell in organic acids, inorganic acids, esters, ketones, and aldehydes. It also offers good mechanical properties. A maximum service temperature of 218ºC (425ºF) is recommended.

Miscellaneous Kalrez® Properties

Many miscellaneous properties are of interest for specific applications. Some of these are unaffected by compound choice, while others vary with hardness or extensibility. As an example, coefficient of friction typically increases as hardness decreases. In general, miscellaneous physical properties are similar to those of Viton® fluoroelastomer.

The information set forth herein is furnished free of charge and is based on technical data that DuPont Dow Elastomers believes to be reliable. It is intended for use by persons having technical skill, at their own discretion and risk. The handling precaution information contained herein is given with the understanding that those using it will satisfy themselves that their particular conditions of use present no health or safety hazards. Because conditions of product use and disposal are outside our control, we make no warranties, express or implied, and assume no liability in connection with any use of this information. As with any material, evaluation of any compound under end-use conditions prior to specification is essential. Nothing herein is to be taken as a license to operate under or a recommendation to infringe on any patents.

*Kalrez® is a registered trademark of E. I. du Pont de Nemours and Company

**Not to be used for specifications