Gasket Fabricators Association Technical Committee Presentation

1. Gasket Fabricators AssociationTechnical Committee Presentation Estimator’s Guide to Basic Gasketing Module 2 of 5 Material Selection December 2009

2. Agenda • Material Selection Criteria • Pros and Cons • PSAs • ASTM F104 & D2000

3. Material Selection Criteria • 4 Main Criteria to consider when selecting a gasket material: • Operating Pressure • Bolt Load • Operating Temperature • Media

4. Operating Pressure • Pressure X Temperature Factor (Service Factor) • Multiply PRESSURE in PSI by TEMPERATURE in °F. • If value > 625,000 – a metallic gasket is required. • Each application is unique! Also consider seating stress, type of flange, etc.

5. Bolt Load • M + Y Values • M = Ratio between residual stress on gasket and internal pressure (Gasket Maintenance Factor). • The higher the “M” value, better against leaks. • Y = minimum gasket seating stress (initial assembly) • M + Y Values not as relevant due to newer gasketing materials. • New gasket constants initiated by Pressure Vessel Research Committee.

6. Operating Temperatures • Elastomers max out at ~ 600° F. • Compressed non-asbestos: 400° F continuous. • Beater-add: 250-300° F. • Flexible Graphite: 800° F. • Continuous v. Intermittent • Non-standard gasketing materials (high temp paper boards, etc.)

7. Media • Primarily affects the elastomer… • So different polymers for each application. • Not just for chemicals and oil/fuel products. • Abrasives, weather, ozone • Food, water, dairy, pharmaceutical • Teflon – excellent chemical resistance! • Envelope or encapsulated gaskets • Flexible Graphite – broad range of chemical resistance.

8. Pros Cost effective. Wide range of durometers – and sponge. Seals under lower compressive loads. Wide range of compositions. Cons Wide range of compositions. Limits on: Temperature Pressure Compression set Pros & Cons:Elastomers

9. Pros Cost effective Higher Pressures. Higher Temperatures. High resistance to seating stress. Cons Dust and slivers. Tool Wear. Pros & Cons:Compressed Non-Asbestos &Beater Add

10. Pros Excellent Chemical Resistance. Electrical Insulator. Anti-Stick Properties. Cons Cold Flow. Pros & Cons:Teflon

11. Pros Good with most chemicals. Good high temperature gasket – up to 5400° F in vacuum. Low creep – reduces retightening. Cons Fragile. Pros & Cons:Flexible Graphite

12. Gaskets with PSAs • Application environments • Adhesive chemistries • Product constructions

13. Surface: Environment: Application: Solvents/Chemicals Surface Texture Time Temperature Surface Contour Temperature Exposure UV Light Exposure Pressure Surface Energy Surface Contamination Factors that can influencePSA success...

14. Three Types of PSA Chemistries • Rubber PSA (Indoor) • Acrylic PSA (Outdoor) • Silicone PSA (Wide Temp)

15. Adhesive Transfer Tape or “Free Film” Double-Coated Tape Single-Coated Tape or Label stock --PSA --Liner --PSA (Exposed) --Carrier --PSA (Liner) --Liner --Carrier --PSA --Liner (optional) Common Constructions

16. Double-Coated Tapes Less conformable Lower temp resistance “Removable” Reinforces substrate Free Film Adhesive More conformable Higher temp resistance “Permanent” Doesn’t reinforce substrate Double-Coated vs. Unsupported Adhesive

17. ASTM F104 & D2000 • Classification systems specifying properties of non-metallic gasket materials. • Non-metallic gasket materials described by specific physical & mechanical characteristics. • Rubber compounds classified under ASTM D2000. • Users can specify required properties. • Suppliers can report product properties. • EXAMPLES: • ASTM F104 F725400 • ASTM D2000-99 M2HK 714 A1-10B38

18. Appendix • ASTM F104 – Nonmetallic Gasket Classification • ASTM D2000 • Elastomer Properties

19. ASTM F104

20. ASTM F104

21. ASTM D2000How to Read a Line Call-OutASTM D2000-99 M 2 HK 7 14 A1-10, B38, C12, EF31,EC88, F15 Z1 The most common material classification system used in O-ring specification is probably "Standard Classification System for Rubber Products in Automotive Applications" or ASTM D 2000. This system is designed to aid in the selection of practical rubber products for specific environments and provided a "line call-out" designation for the specification of elastomer seal materials. • Specification Revision • This indicates the revision year of D2000 to which the line call-out makes reference. • Measurement Units • If an M is present, metric units will be used for tensile strength, termperature, and tear strength (MPa, °C, and kN/m respectively). If no M is present, English units will be used (psi, °F, and ppi respectively). • Grade Number • Indicates the level of test requirements to which a material may be subjected. Example, Grade – basic properties; Grades 2-9 require additional testing. • Type and Class • See next page for most common polymers type and class.

22. ASTM D 2000Type & Class

23. ASTM D2000How to Read a Line Call-OutASTM D2000-99 M 2 HK 7 14 A1-10, B38, C12, EF31,EC88, F15 Z1 • Hardness (Durometer) • This number indicates durometer range in Shore A units (± 5 pts.). Example indicates a harness of 70±5 durometer. • Tensile Strength • Next 2 digits show minimum tensile strength – 14 in example above (metric) or 14MPa. If non-metric would be 20 (2031 psi). • Additional Requirement Suffixes • Letter & number combinations that indicate a material’s test and performance criteria per the Grade number indicated. Example above of A1-10, B38, EF31, EC88, F15 Z1. (see next slide)

24. Additional Requirements Suffix

25. Elastomer Properties

26. More to Come! • Module 1: Understanding the Application • Module 2: Material Selection • Module 3: Cutting/Processing Techniques • Module 4: Value Adding • Module 5: Monday Morning Quarterback: Actual Results vs. Estimation

27. Thank You! We appreciate your time and attention. Questions?