For Performance and Value in Chemical Processing Industry (CPI … · 2019. 10. 16. · Teflon™ PFA With the same 260 °C (500 °F) upper service temperature as Teflon ™ PTFE,

For Performance and Value in Chemical Processing Industry (CPI) Equipment

Teflon™/Tefzel™

Fluoropolymer Resins

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Teflon™/Tefzel™ Fluoropolymer Resins

Table 1. Physical Properties of Chemours Fluoropolymers

Property Test Method Unit Teflon™ PTFE Teflon™ FEP Teflon™ PFA Tefzel™ ETFE

Tensile Strength * MPa (psi x 1,000)

21–35(3–5)

23–28(3.4–4.1)

25–28(3.6–4.0)

40–47(5.8–6.7)

Elongation * % 200–400 300 300 150–300

Flexural Modulus D790 MPa (psi x 1,000)

345–620(50–90)

620(90)

590–625(85–90)

1,200(170)

Hardness D2240 Shore D 50–65 56 55–57 63–72

Melting Point D3418 °C (°F)

327(621)

260(500)

305(582)

255–280(491–536)

Upper Service Temperature UL 746B**20,000 hr

°C (°F)

260(500)

204(400)

260(500)

135–150(275–302)

*Tensile Strength and Elongation Test Methods: PTFE, D4894/4895; FEP, D2116; PFA, D1708 **This is a test for wire and cable; there is no standard test for resins.

Protect Equipment Investment, Fight Contamination with Teflon™ and Tefzel™ Fluoropolymer ResinsWith today’s competitive environment in the chemical process industries, equipment lifetime and product quality are more crucial than ever. In fluid handling components and accessories, process equipment, and containers for storage and transport, Teflon™ and Tefzel™ fluoropolymer resins can help reduce costs and maintain product purity.

Lower Installed Cost Equipment made with Teflon™ and Tefzel™ fluoropolymer resins can cost less than similar equipment made from exotic metals or alloys.

Cut Unscheduled Downtime Even with maintenance intervals spaced out to increase productivity, equipment made with Teflon™ and Tefzel™ fluoropolymer resins is often more reliable than alternatives.

Extend Service Life Equipment made using Teflon™ and Tefzel™ fluoropolymer resins lasts longer. Our high-performance fluoropolymers outperform metals and other polymers in resisting attack by more chemicals and solvents over a wider temperature range.

Reduce Lifetime Costs Along with lower installed cost, longer service and reduced maintenance requirements can result in lower lifetime costs for process equipment with Teflon™ and Tefzel™ fluoropolymer resins.

Guard Against Contamination Teflon™ and Tefzel™ fluoropolymer resins help meet demands for product purity because they resist corrosion. In addition, they contain no additives that could extract out and contaminate process streams.

Long-Lasting, Economical Alternatives to Exotic Metals and Alloys As linings for carbon steel and glass fiber-reinforced plastic equipment, Chemours fluoropolymers deliver outstanding corrosion resistance at lower cost than exotic metals and alloys. In some cases, the fluoropolymer solution costs only 25% as much as alternatives using alloys.

Chemours fluoropolymers can perform well in self-supporting structures such as tubing, column internals, pumps, pipes, valves, and fittings. They also serve in gaskets, seals, and other accessories for metal and glass-lined equipment and in coatings for metal that reduce friction and ease cleaning.

Four Fluoropolymers, Four Ways to Manage Corrosion Chemours supplies three types of Teflon™ fluoropolymer resin to meet your needs for the best chemical resistance available. In addition, Tefzel™ fluoropolymer resin gives nearly the same level of chemical resistance, plus superior mechanical properties and easier processing that are an asset in many applications.

Typical physical properties for Chemours fluoropolymers are shown in Table 1. For detailed information on chemical resistance, contact your Chemours representative.

All of the Teflon™ fluoropolymers are available in dispersion form for coating or impregnating fabric or metallic substrates. Some are offered as powders for spray and bake coatings.

Teflon™ PTFE The original Teflon™ fluoropolymer combines the ultimate in chemical resistance with a service temperature capability up to 260 °C (500 °F). Teflon™ PTFE granular resins are typically formed into simple shapes by compression and sintering. Technologies have been developed to form linings for pipes, valves, and other components, as well as sheets, tubes, and other useful shapes. Complex parts can be machined from stock shapes.

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Teflon™ FEP Using conventional thermoplastic processing methods such as extrusion and injection molding, Teflon™ FEP can be made into linings, tubing, sheets, film, and other products for the CPI. Its chemical resistance is very similar to Teflon™ PTFE. The upper service temperature of Teflon™ FEP is 204 °C (400 °F).

Teflon™ PFA With the same 260 °C (500 °F) upper service temperature as Teflon™ PTFE, along with thermoplastic processing, Teflon™ PFA is uniquely qualified to meet needs for complex injection-molded components or extruded profiles that operate at high temperatures. Linings of Teflon™ PFA can be formed using rotational molding and lining technology. In chemical resistance, it is essentially the same as the other Teflon™ fluoropolymers.

Tefzel™ ETFE Tefzel™ ETFE has nearly the same chemical resistance performance as Teflon™ PTFE and offers superior abrasion resistance, strength, and stiffness. It is formed using thermoplastic molding, including extrusion and rotational molding and lining. The upper service temperature for Tefzel™ ETFE is 150 °C (302 °F).

Selecting the Right Material Although fluoropolymers are well proven for service in a wide variety of chemical environments, their suitability for use should be thoroughly tested before they are selected as materials of construction. The most reliable predictors of success are good experience with similar uses, as well as laboratory and field testing.

Laboratory screening tests of chemical resistance can be performed at pressures above atmospheric with a Roberts or Atlas cell at atmospheric pressure. Tests of fluoropolymer coupons that have been suspended in process streams also provide useful information about the chemical compatibility of the lining.

Field testing with the actual process stream for which the application is intended should follow laboratory work. Such tests can be done with fluoropolymer-lined blind flanges on process piping or equipment. Exposure is typically tested for three months, but may be much longer. The performance of pilot plant components and equipment made from the material under consideration is another excellent indication of suitability.

Fluid Handling Systems Complete systems for handling aggressive chemicals can be designed with piping, valves, fittings, pumps, and expansion joints made with Teflon™ and Tefzel™ fluoropolymer resins. Hoses, seals, and gaskets are made with Teflon™ PTFE.

For broad applications in chemical processing, fluid handling components are usually engineered by lining carbon steel or glass fiber-reinforced plastic housings with Teflon™ or Tefzel™ fluoropolymers. Internals are often made from solid Teflon™ or Tefzel™ fluoropolymer resins. Components made of solid fluoropolymer are used where pressures and stresses are moderate. For example, tubing of Teflon™ PFA is widely used for transporting ultrapure, aggressive fluids for processing semiconductors.

Hose

Courtesy Crane Resistoflex

Chemical transfer hose lined with Teflon™ PTFE with a flared-through design allows protection of all wetted surfaces, eliminating metal corrosion and process contamination.

Piping


Carbon steel pipe lined with Teflon™ fluoropolymer is an industry standard for handling corrosive fluids.

Fittings Complex fittings can be constructed to reduce the need for flanged connections.

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Valves

A number of valve types are lined with fluoropolymers for corrosion resistance. The plug valve is lined with Teflon™ PFA, and its plug is encapsulated in the same material using melt processing technology. During the molding process, the lining and encapsulant are locked into dovetail recesses in the valve body and plug. The lubricity of Teflon™ PFA provides low operating torque for a design having large contact areas for good sealing.

Expansion Joints


Resistoflex® expansion joints are contour molded of Teflon™ PTFE by an exclusive patented process. They are corrosion-resistant, non-aging, with extraordinary flex life and unmatched reliability. They offer a low spring rate to protect stress-sensitive glass, graphite, or FRP equipment and are cost-effective. The convoluted PTFE expansion joints are flared over the flanges to eliminate the need for separate gaskets.

Pumps Pumps and components made with fluoropolymers are widely used to help prevent contamination of process streams or resist corrosion to extend service life. The air-powered diaphragm pump has all wetted components made of Teflon™ PTFE, Teflon™ PFA, or Teflon™ FEP. It is used to handle ultrapure, aggressive fluids in semiconductor manufacturing and chemical processing.

This air-operated pump diaphragm is made of Teflon™ PTFE backed with reinforced elastomers. Because only the side that is Teflon™ PTFE is in contact with fluids, the diaphragm is compatible with nearly any fluid. The diaphragm has a special design featuring a strong bond between elastomers and Teflon™ PTFE to promote uniform flexing for an extended service life. This design received a Plunkett Award for Innovation with Teflon™.

Gaskets

Courtesy Triangle Fluid Controls Ltd. — Proud Manufacturer of Durlon® Sealing Products

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Teflon™ PTFE is a valuable material for gaskets because it is inert to almost any chemical and can be used over a wide range of temperatures. Gasketing of Teflon™ PTFE is supplied as preformed gaskets or sheeting and tape that can be cut to size.

Solid (virgin) Teflon™ PTFE is common; however, in many gasket materials, a filler is added to reduce material creep. A special manufacturing technology can be used to produce gasketing of Teflon™ PTFE with a strong fibrillated and expanded microstructure. In extreme conditions, another design feature can include PTFE sealing material with a metallic core covered wtih Teflon™ PTFE or the fluoropolymer wetted surface is contained by a spiral-wound alloy metal strip.

Process Equipment Linings of fluoropolymers extend the life of process equipment in corrosive service.

Linings can be applied to steel structures by adhesive bonding fluoropolymer sheeting backed with glass fabric. Seams are joined by thermoplastic welding. Glass-backed sheeting is used to construct equipment with an exterior shell of reinforced thermosetting plastic (RTP). Linings of sheeting can be unbonded, or loose, and supported only at nozzles and other openings. Thick coatings of melt-processible fluoropolymer can be made by the spray and bake process or rotational lining (rotolining). Rotomolding with thermoplastic fluoropolymers is used to line equipment.

ColumnsColumn sections have been rotolined with Tefzel™ ETFE. Rotolining produces seamless linings and can be used for complex shapes difficult to line by other methods. In rotolining, fluoropolymer powder is placed in a steel equipment shell and openings are sealed. Then the shell is rotated in three dimensions in an oven so that the powder melts and flows, evenly covering the shell’s interior.

Vessels

RL Industries constructed these dual-laminate scrubber vessels of sheeting of Tefzel™ ETFE backed with glass fabric. Sheets were welded together to fabricate an interior shell, and then a carbon fiber veil and dry glass fiber fabrics were applied. The layers were vacuum-infused and cured. These vessels serve for removing pollutants from emissions at chemical plants.

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This vessel was lined by Electro Chemical using sheet made of Teflon™ PFA 951HP Plus and welded with PFA cap strip. The worker is helium leak testing the welds to ensure equipment integrity. The helium leak test can detect flaws that are just 1/100th the size of the smallest leak a spark test can find.

Components Internal components for towers are made from fluoropolymers to resist corrosion and help prevent contamination. They also resist damage due to rapid temperature cycling. Typical components include ladder distributors, orifice riser distributors, and packing rings.

Transportation and Storage Equipment Chemours fluoropolymers are used in containers that help meet the industry’s increasing demands for durability as well as guarding product purity. Because of the chemical resistance of Teflon™ and Tefzel™ fluoropolymer resins, these containers can be used with a wide range of chemicals.

Containers are lined in the same manner as columns, tanks, and other equipment or made of solid fluoropolymer.

TanksRotationally molded 5,000-L (1,320-gal) tanks of Teflon™ PFA have been designed for storing ultrapure and aggressive fluids. A 750-L (198-gal) tank made by the same method housed in a stainless steel shell so it can serve as a shipping container.

Small Containers Bottles molded from Teflon™ FEP and Teflon™ PFA guard the purity of reagents for sensitive analyses.

Tank TrailersTank trailers have been made with a dual-laminate construction with a lining of Tefzel™ ETFE sheeting and a RTP structural shell. Truckers can haul a much wider range of aggressive chemicals than in steel or unlined RTP tank trailers. The smooth, nonporous lining of Tefzel™ ETFE permits easy cleaning when cargoes are changed.

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Cooling Water Outlet

Cooling Water Inlet

Concentrated Solution

Dilute Solution Inlet

Cooling Water

Unabsorbed Gas to Tower

Concentrated Solution Acid Outlet

Tubing of “Q” Resin

Other Applications

Sampling Equipment The process sampler is a closed system for in-line sampling of chemical fluid streams. The design allows removal and isolation of a sample without operator or atmospheric exposure to the fluid. All wetted surfaces, including the sampler valve body and sample bottle, are made of Teflon™ PFA and Teflon™ PTFE. With Teflon™ fluoropolymer resins, the sampler can be used with almost any chemical and sample purity is protected.

Cooler/Absorber

For stripping aggressive gases from process streams, a cooler/absorber is made with tubing made of a patented thermally conductive compound based on Teflon™ PFA. The unit’s outer shell and heads are lined with Teflon™ PTFE. In design, they are similar to heat exchangers made with Teflon™ fluoropolymers. They function like a column filled with temperature-controlled packing, with cooling water flowing upward through the tubing. Gas and droplets of water or another absorbing medium flow downward through the column. The gas dissolves in the absorbing medium, which collects on the outer tubing wall.

© 2018 The Chemours Company FC, LLC. Teflon™, Tefzel™, and any associated logos are trademarks or copyrights of The Chemours Company FC, LLC. Chemours™ and the Chemours Logo are trademarks of The Chemours Company.

Replaces: H-71047

C-11666 (11/18)

For more information, visit teflon.comCAUTION: Do not use or resell Chemours materials in medical applications involving implantation in the human body or contact with internal bodily fluids or tissues unless agreed to by Seller in a written agreement covering such use. For further information, please contact your Chemours representative. For medical emergencies, spills, or other critical situations, call (866) 595-1473 within the United States. For those outside of the United States, call (302) 773-2000.

The information set forth herein is furnished free of charge and based on technical data that Chemours 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 are outside our control, Chemours makes no warranties, express or implied, and assumes 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 any patents.

NO PART OF THIS MATERIAL MAY BE REPRODUCED, STORED IN A RETRIEVAL SYSTEM OR TRANSMITTED IN ANY FORM OR BY ANY MEANS ELECTRONIC, MECHANICAL, PHOTOCOPYING, RECORDING OR OTHERWISE WITHOUT THE PRIOR WRITTEN PERMISSION OF CHEMOURS.

HOW TO USE THE TEFLON™ BRAND NAME WITH YOUR PRODUCT

Teflon™ is a registered trademark of Chemours for its brand of fluoropolymer resins, coatings, films, and dispersions. The Teflon™ brand name is licensed by Chemours in association with approved applications. Without a trademark license, customers may not identify their product with the Teflon™ brand name, as Chemours does not sell such offerings with the Teflon™ trademark. Unlicensed customers may refer to the Chemours product offering with only the Chemours name and product code number descriptor as Chemours sells its product offerings. There are no fair use rights or exhaustion of rights to use the Teflon™ trademark from buying from Chemours, a Chemours customer, or a distributor without a trademark license from Chemours.

If you are interested in applying for a trademark licensing agreement for the Teflon™ brand, please visit www.teflon.com/license

http://www.teflon.com/license

Documents

For Performance and Value in Chemical Processing Industry (CPI … · 2019. 10. 16. · Teflon™ PFA With the same 260 °C (500 °F) upper service temperature as Teflon ™ PTFE,