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Flexitallic L.P. 6915 Highway 225 Deer Park, TX 77536 USA Tel: 281 604 2400 Flexitallic Ltd. PO Box 3, Marsh Works Dewsbury Road, Cleckheaton West Yorkshire, BD19 5BT England Tel: 44 1274 851273 Flexitallic Sealing Technology (Suzhou) Co., Ltd. Building 3 South 688 Pangjin Road Wujiang Export Processing Zone Wujiang, Jiangsu P.R. China 215200 Tel: 86 512 6303 2839 http://www.flexitallic.com DISTRIBUTOR Revised 02-12-13 AC 06-2011 5000 Page CONTENTS MANUFACTURING UNITS 2 INTRODUCTION 3 GASKET IDENTIFICATION 4 AVAILABLE GASKET MATERIALS 5 GASKET SELECTION 6 DIMENSIONAL DATA TABLE 1 - STYLE CG & CGI TO ASME B16.20 TO SUIT ASME B16.5 FLG - IMPERIAL SIZES TABLE 2 - STYLE CG & CGI TO ASME B16.2O TO SUIT ASME B16.5 FLG - METRIC SIZES TABLE 3 - INNER RING DIMENSIONS FOR STYLE CGI TO ASME B16.20 TABLE 4 - STYLE CG & CGI TO SUIT SMALL DIA SCREWED OR SLIP-ON FLG TABLE 5 - MAXIMUM BORE OF ASME B16.5 FLG TABLE 6 - STYLE CG & CGI TO ASME B16.20 TO SUIT LARGE DIA ASME B16.47 SERIES B FLG - IMPERIAL SIZES TABLE 7 - STYLE CG & CGI TO ASME B16.20 TO SUIT LARGE DIA ASME B16.47 SERIES B FLG - METRIC SIZES TABLE 7 - STYLE CG & CGI TO ASME B16.20 TO SUIT LARGE DIA ASME B16.47 SERIES A AND BS 3293 FLG TABLE 8 - STYLE CG & CGI TO SUIT LARGE DIA FLG - IMPERIAL SIZES TABLE 9 - STYLE CG & CGI TO SUIT LARGE DIA FLG - METRIC SIZES TABLE 10 - STYLE CG & CGI TO SUIT LARGE DIA FLG TABLE 11 - STYLE CG & CGI TO BS 3381 TO SUIT BS 1560 & ASME B16.5 FLG - IMPERIAL SIZES TABLE 12 - STYLE CG & CGI TO BS 3381 TO SUIT BS 1560 & ASME B16.5 FLG - METRIC SIZES TABLE 13 - STYLE CG & CGI TO SUIT BS10 FLG TABLE 14 - STYLE CG & CGI TO BS 4865 PART 2 TO SUIT BS 4504 FLG TABLE 15 - STYLE CG & CGI TO SUIT DIN FLANGES TABLE 16 - STYLE R TO SUIT ASME B16.5 AND BS 1560 FLG TABLE 17 - STYLE RIR TO SUIT ASME B16.5 AND BS 1560 FLG TABLE 18 - STYLE CG & CGI TO SUIT JIS FLG TABLE 19 - STYLE CG & CGI TO SUIT JIS FLG TABLE 20 - STYLE CG-RJ & CGI-RJ REPLACEMENTS FOR RING JOINT GASKETS TABLE 21 - STYLE 625 FOR CLAMP-TYPE AND OTHER NON-STANDARD FLANGE ASSEMBLIES 7 8 9 10 10 11 12 14 15 16 18 20 22 23 24 25 26 27 28 29 29 30 31 USEFUL TECHNICAL DATA ASSEMBLY TECHNIQUES TABLE 22 - RECOMMENDED TORQUE CG SPIRAL WOUND GASKETS TABLE 23 - RECOMMENDED TORQUE CGI SPIRAL WOUND GASKETS TABLE 24 - BOLTING DATA FOR ASME B16.5 AND BS 1560 FLG TABLE 25 - FACING DIMENSIONS FOR ASME B16.5 AND BS 1560 FLG 32 32 33 34 35 36 SPECIAL APPLICATION GASKETS SPECIAL CGI WITH SPIRAL WOUND OUTER RING GASKETS FOR HEAT EXCHANGERS CARRIER RING GASKETS STYLE LS & LSI LOW STRESS GASKETS BOILER CAP AND MANHOLE COVER GASKETS TABLE 26 - STYLE M, MC & MCS TABLE 27 - STYLE T THERMICULITE 835 HEAT TREATED INCONEL X-750 SPIRAL WOUND GASKETS MULTI-CLASS SPIRAL WOUND GASKETS BAKER GASKETS 37 37 38 39 40 41 42 43 44 45 YOUR GLOBAL GASKET PROVIDER 1 MANUFACTURING UNITS Owned Manufacturing Plants Licensees - continuing Flexitallic Ltd. Cleckheaton,Yorkshire, UK Tel: +44 1274 851273 Engineering & Chemical Productions Lagos State, Nigeria Tel: +234 1 804 3808 Flexitallic L.P. Deer Park,TX, USA Tel: +1 281 604 2400 Flexitallic Sealing Technology (Suzhou) Co., Ltd. Wujiang, Jiangsu, P.R. China Tel: +86 512 6303 2839 AGS Flexitallic, Inc. Edmonton, Alberta, Canada Tel: +1 780 466 5050 Joint Ventures Equiter S.A. de C.V. Guadalajara, Mexico Tel: +52 3 612 8483 Branch Offices & Warehouses Flexitallic Ltd. Aberdeen, Scotland, UK Tel: +44 1224 725241 Licensees Dragon Industrial Services Pembroke, UK Tel: +44 1646 622200 Eriks BV. Rotterdam, Netherlands Tel: +31 72 514 1514 Eriks Pte Ltd. Singapore Tel: +65 62 72 24 05 GHX, Inc. Houston, TX, USA Tel: +1 713 222 2231 Henry Gallacher Ltd. Stockton, Teesside UK Tel: +44 1642 750111 Industrial Gasket & Supply Torrance, CA, USA Tel: +1 310 530 1771 Dooley Gasket and Seal Co. Broomall, PA, USA Tel: +1 610 328 2720 Lake Charles Rubber Lake Charles, LA, USA Tel: +1 337 433 1002 Special Piping Material Ltd. Delta State, Nigeria Tel: +234 53 254 767 Allied Sealing Brisbane, Australia Tel: +61 (0)7 3212 5399 Note: Over 500 stocking distributors in over 40 countries strategically located to serve the world. 2 YOUR GLOBAL GASKET PROVIDER INTRODUCTION FIRST AND FOREMOST The concept of spiral wound gasket construction was originated by Flexitallic in 1912, inaugurating the beginning of a new era in safe, effective sealing. The primary purpose for this development was the increasingly severe temperatures and pressures used by U.S. refinery operators in the first half of the century. Metal Strip Filler Material The necessity for a gasket to have the ability to recover cannot be over emphasized. The effects of pressure and temperature fluctuations, the temperature differential across the flange face, together with bolt stress relaxation and creep, demand a gasket with adequate flexibility and recovery to maintain a seal even under these varying service conditions. The Flexitallic Spiral Wound Gasket is the precision engineered solution to such problems, meeting the most exacting conditions of both temperature and pressure in flanged joints and similar assemblies and against virtually every known corrosive and toxic media. This publication is designed to facilitate the specification and ordering of standard Flexitallic Spiral Wound Gaskets. Dimensional data for the basic styles - Style CG, Style CGI, Style R and Style RIR are detailed on respective tables. YOUR GLOBAL GASKET PROVIDER 3 GASKET IDENTIFICATION Gaskets are color coded to help expedite the selection and identity of the gaskets you need. The color on the outside edge of the centering ring identifies both the winding and filler materials. The metallic winding material is designated by a solid color. The filler materials are designated by color stripes at equal intervals on the outside edge of the centering ring. Flexitallic color coding meets the industry standard for metal and filler materials listed in ASME B16.20. METALLIC WINDING MATERIALS The metallic winding material is designated by a solid color identification around the outside edge of the centering ring. 304SS Yellow 316LSS Green 317L Maroon 321SS Turquoise 347SS Blue 310SS No color 304LSS No color 309SS No color 430SS No color Alloy 20 Black Titanium ® Purple Inconel® 600/625 Gold Incoloy® 800/825 White Inconel® X750 No Color Hastelloy ® C276 Beige Hastelloy ® B2 Brown Nickel 200 Red Zirconium No color Carbon Steel Silver PTFE White Stripe Flexicarb® Gray Stripe NON METALLIC FILLERS The gasket filler materials are designated by a number of stripes placed at equal intervals around the 4 Monel® Orange Duplex No color Flexite Super ® Pink Stripe Ceramic Light Green Stripe outside edge of the centering ring. Thermiculite® 835 Light Blue Stripe YOUR GLOBAL GASKET PROVIDER available gasket Materials METAL WINDING STRIP AS STANDARD Stainless Steel type 304 316L OTHERS Stainless Steel ALLOY 20 MONEL® TITANIUM® NICKEL® 200 INCONEL® HASTELLOY® INCOLOY® type 304L 309 310 316Ti 317L 321 347 430 17-7PH type 600 625 X-750 type B-2 B-3 C276 type 800 825 FILLER MATERIAL Flexicarb® flexible graphite Thermiculite® 835 Flexite Super® PTFE Mica Ceramic Non-sintered PTFE GUIDE RING MATERIAL AS STANDARD Carbon Steel OTHERS Stainless Steel type 304 304L 316 316L 316Ti 310 321 347 410 600 625 MONEL® TITANIUM® NICKEL INCOLOY® type 800 825 ALLOY 20 HASTELLOY® type B-2 B-3 C276 Thermiculite®, FLEXITALLIC’S proprietary high-temperature, sealing material is comprised of chemically exfoliated and thermally exfoliated vermiculite. This revolutionary patented product simulates the structure of exfoliated graphite but with one notable exception … gaskets made with Thermiculite® maintain their integrity, even at extreme temperatures. Thermiculite is thermally stable, ensuring against thermal oxidation, at temperatures in excess of 1800ºF (Thermiculite® 835). INCONEL® DUPLEX ZIRCONIUM® TANTALUM® COPPER PHOS-BRONZE NOTES: Selected materials should be compatible with operating temperature and chemicals. If in doubt, contact Flexitallic Technical Department. If PTFE is subjected to temperatures above 250°C (500°F) decomposition starts to occur slowly, increasing rapidly above 400°C (750°F). Care should be taken to avoid inhaling the resultant fumes, which may produce hazardous effects. identification reQuireMents YOUR GLOBAL GASKET PROVIDER 5 GASKET SELECTION Style CG - Utilizes an external ring which accurately centers gasket on flange face, provides additional radial strength to prevent gasket blow-out and acts as a compression stop. A general purpose gasket suitable for use with flat face and raised face flanges up to and inclusive of class 2500. See note at bottom of page 8 for inner ring requirements. WHAT STYLE OF GASKET SHOULD I SELECT? Style CGI - A Style CG gasket fitted with internal ring which gives an additional compression limiting stop and provides heat and corrosion barrier protecting gasket windings and preventing flange erosion. Suitable for use with flat face and raised face flanges. See note at bottom of page 8 for inner ring requirements. SELECTION GUIDE Style R - Basic construction type. Inner and outer diameters are reinforced with several plies of metal without filler to give greater stability and better compression and sealing characteristics. Suitable for tongue and groove or male and female or grooved to flat face flange assemblies. Style RIR - Solid inner metal ring acts as a compression stop and fills the annular space between flange bore and the inside diameter of the gasket. Designed to prevent accumulation of solids, reduce turbulent flow of process fluids and minimize erosion at flange faces. Suitable for male and female pipe flanges. Published as an indication of which Flexitallic spiral wound gasket best suits different pipe flange configurations and service conditions. Flange Face Raised Face Flat Face Male and Female Tongue and Groove Flat Face to Recess Style CG Style CG Style R* Style R* Style R* Style CGI** Style CGI** Style RIR** Style RIR** Style RIR** Recommended Gasket Style For general duties Recommended Gasket Style For high pressure/ temperature duty, also for gaskets with PTFE filler, corrosive or fluctuating pressure or temperature service conditions. *It is essential that Style R gaskets are fitted with a compression stop. Without a correctly dimensioned stop the gasket can easily be over-compressed resulting in failure. To provide a compression stop the depth of the tongue, groove or recess should be controlled to provide optimum compressed gasket thickness with metal to metal contact on the flange faces (see tables on Page 28 and 32). ** See note at bottom of page 8 for inner ring requirements. 6 YOUR GLOBAL GASKET PROVIDER DIMENSIONAL DATA STYLE CG & CGI GASKETS TO SUIT STANDARD RAISED FACE AND FLAT FACE FLANGES SPECIAL GASKETS *Style CGI *Style CG Gaskets of special design can be engineered and fabricated using the same basic fundamentals of Flexitallic Spiral Wound Gasket design and construction to cover a wide range of applications in installations for which there are no industry-wide standards. Special gaskets have been designed for valves, pumps, compressors, turbines, boilers, heat exchangers, etc. Consult with Flexitallic engineers as early in the design stage as possible. All CG and CGI Gaskets for these standard flanges are 0.175 in (4.5mm) thick, fitted with 0.125 in (3.2mm) thick solid metal rings, unless otherwise stated. GOVERNMENT SPECIFICATIONS Flexitallic Spiral Wound Gaskets are available in accordance with Military Specifications MIL-G24716, and MIL-G-15342, latest revisions. When making an inquiry, refer to the proper Government Specification number. Flexitallic style CG and CGI Spiral Wound gaskets can be manufactured in accordance with all relevant gasket standards to suit the following flange designations. Please note that gaskets for non-standard flanges are also readily available. ASME B16.5 BS 1560 BS 10 ASME B16.47 SERIES B (API 605) ASME B16.47 SERIES A (MSS SP 44) BS 4504 DIN FLANGES JIS FLANGES WHEN ORDERING PLEASE SPECIFY EXAMPLE GASKET STYLE FLEXITALLIC STYLE “CGI” SPIRAL WOUND GASKET NOMINAL PIPE SIZE (NPS) 4” PRESSURE RATING CLASS 900 GASKET STANDARD ASME B16.20 WINDING MATERIALS 316L/FLEXICARB (FG) OUTER RING MATERIAL CARBON STEEL INNER RING MATERIAL 316L Note: Please select correct gasket style for your particular application. See page 6 “Gasket Selection”. YOUR GLOBAL GASKET PROVIDER 7 STYLE CG & CGI* TO ASME B16.20 TO SUIT ASME B16.5 FLANGES TABLE 1 NOM PIPE SIZE OUTSIDE DIAMETER OF SEALING ELEMENT INNER DIAMETER OF SEALING ELEMENT CLASS CLASS 150, 300, 900, 1500, 400, 600 2500 OUTER DIAMETER OF CENTERING RING CLASS 150 CLASS 300 CLASS 400 CLASS 600 CLASS 900 CLASS 1500 CLASS 2500 CLASS 150 CLASS 300 CLASS 400 CLASS 600 CLASS 900 CLASS 1500 CLASS 2500 1/4 7/8 - 1/2 1/2 1/2 1/2 - - - 1-3/4 1-3/4 1-3/4 1-3/4 - - - 1/2 1-1/4 1-1/4 3/4 3/4 3/4 3/4 3/4 3/4 3/4 1-7/8 2-1/8 2-1/8 2-1/8 2-1/2 2-1/2 2-3/4 3/4 1-9/16 1-9/16 1 1 1 1 1 1 1 2-1/4 2-5/8 2-5/8 2-5/8 2-3/4 2-3/4 3 1-1/4 1-1/4 2-5/8 2-7/8 2-7/8 2-7/8 3-1/8 3-1/8 3-3/8 1 1-7/8 1-7/8 1-1/4 1-1/4 1-1/4 1-1/4 1-1/4 1-1/4 2-3/8 2-3/8 1-7/8 1-7/8 1-7/8 1-7/8 1-9/16 1-9/16 1-9/16 3 3-1/4 3-1/4 3-1/4 3-1/2 3-1/2 4-1/8 1-1/2 2-3/4 2-3/4 2-1/8 2-1/8 2-1/8 2-1/8 1-7/8 1-7/8 3-3/8 3-3/4 3-3/4 3-3/4 3-7/8 3-7/8 4-5/8 2 3-3/8 3-3/8 2-3/4 2-3/4 2-3/4 2-3/4 2-5/16 2-5/16 2-5/16 4-1/8 4-3/8 4-3/8 4-3/8 5-5/8 5-5/8 5-3/4 2-1/2 3-7/8 3-7/8 3-1/4 3-1/4 3-1/4 3-1/4 2-3/4 2-3/4 2-3/4 4-7/8 5-1/8 5-1/8 5-1/8 6-1/2 6-1/2 6-5/8 3 4-3/4 4-3/4 4 4 4 4 3-3/4 3-5/8 3-5/8 5-3/8 5-7/8 5-7/8 5-7/8 6-5/8 6-7/8 7-3/4 3-1/2 5-1/4 5-1/4 4-1/2 4-1/2 4-1/8 4-1/8 4-1/8 4-1/8 - 6-3/8 6-1/2 6-3/8 6-3/8 7-1/2 7-3/8 - 4 5-7/8 5-7/8 5 5 4-3/4 4-3/4 4-3/4 4-5/8 4-5/8 6-7/8 7-1/8 7 7-5/8 8-1/8 8-1/4 9-1/4 4-1/2 6-1/2 6-1/2 5-1/2 5-1/2 5-5/16 5-5/16 5-5/16 5-5/16 - 7 7-3/4 7-5/8 8-1/4 9-3/8 9-1/8 - 5-13/16 5-13/16 5-13/16 5-5/8 9-3/4 10 11 1-7/8 5 7 7 6-1/8 6-1/8 5-5/8 7-3/4 8-1/2 8-3/8 9-1/2 6 8-1/4 8-1/4 7-3/16 7-3/16 6-7/8 6-7/8 6-7/8 6-3/4 6-3/4 8-3/4 9-7/8 9-3/4 10-1/2 11-3/8 11-1/8 12-1/2 8 10-3/8 10-1/8 9-3/16 9-3/16 8-7/8 8-7/8 8-3/4 8-1/2 8-1/2 11 12-1/8 12 12-5/8 14-1/8 13-7/8 15-1/4 10 12-1/2 12-1/4 11-5/16 11-5/16 10-13/16 10-13/16 10-7/8 10-1/2 10-5/8 13-3/8 14-1/4 14-1/8 15-3/4 17-1/8 17-1/8 18-3/4 12 14-3/4 14-1/2 13-3/8 13-3/8 12-7/8 12-7/8 16-1/8 16-5/8 16-1/2 12-3/4 12-3/4 12-1/2 18 19-5/8 20-1/2 21-5/8 14 16 15-3/4 14-5/8 14-5/8 14-1/4 14-1/4 14 14-1/4 - 17-3/4 19-1/8 19 19-3/8 20-1/2 22-3/4 - 16 18-1/4 18 16-5/8 16-5/8 16-1/4 16-1/4 16-1/4 16 - 20-1/4 21-1/4 21-1/8 22-1/4 22-5/8 25-1/4 - 18 20-3/4 20-1/2 18-11/16 18-11/16 18-1/2 18-1/2 18-1/4 18-1/4 - 21-5/8 23-1/2 23-3/8 24-1/8 25-1/8 27-3/4 - 20 22-3/4 22-1/2 20-11/16 20-11/16 20-1/2 20-1/2 20-1/2 20-1/4 - 23-7/8 25-3/4 25-1/2 26-7/8 27-1/2 29-3/4 - 24-3/4 24-3/4 24-1/4 - 28-1/4 30-1/2 30-1/4 31-1/8 - 24 27 26 3/4 24-3/4 24-3/4 24-3/4 33 35-1/2 DIMENSIONS IN INCHES. *For Style CGI - see Table 3 for Inner Ring dimensions Gasket sizes 1/4” to 3” Class 300, 400 & 600 as well as sizes 1/2” to 2-1/2” Class 900 & 1500 are identical within their respective nominal pipe sizes, therefore inventories need not be duplicated. In accordance with ASME B16.20, Inner Rings are mandatory for the following flange designations (see Table 3). Class 900 - NPS 24 to 48 Class 1500 - NPS 12 to NPS 24 Class 2500 - NPS 4 to NPS 12 All PTFE filled gaskets All flexible graphite gaskets unless otherwise requested by the customer ASME B16.20 does not include dimensions for NPS 1/4, 3-1/2, or 4-1/2, or Class 400 Flanges up to NPS 3 and Class 900 Flanges up to NPS 2-1/2. 8 YOUR GLOBAL GASKET PROVIDER STYLE CG & CGI* TO ASME B16.20 TO SUIT ASME B16.5 FLANGES TABLE 2 NOM PIPE SIZE OUTSIDE DIAMETER OF SEALING ELEMENT CLASS CLASS 150, 300, 900, 1500, 400, 600 2500 INNER DIAMETER OF SEALING ELEMENT OUTER DIAMETER OF CENTERING RING CLASS 150 CLASS 300 CLASS 400 CLASS 600 CLASS 900 CLASS 1500 CLASS 2500 CLASS 150 CLASS 300 CLASS 400 CLASS 600 CLASS 900 CLASS 1500 CLASS 2500 1/4 22.2 - 12.7 12.7 12.7 12.7 - - - 44.5 44.5 44.5 44.5 - - - 1/2 31.8 31.8 19.1 19.1 19.1 19.1 19.1 19.1 19.1 47.8 54.1 54.1 54.1 63.5 63.5 69.9 3/4 39.6 39.6 25.4 25.4 25.4 25.4 25.4 25.4 25.4 57.2 66.8 66.8 66.8 69.9 69.9 76.2 1 47.8 47.8 31.8 31.8 31.8 31.8 31.8 31.8 31.8 66.8 73.2 73.2 73.2 79.5 79.5 85.9 1-1/4 60.5 60.5 47.8 47.8 47.8 47.8 39.6 39.6 39.6 76.2 82.6 82.6 82.6 88.9 88.9 104.9 1-1/2 69.9 69.9 54.1 54.1 54.1 54.1 47.8 47.8 47.8 85.9 95.3 95.3 95.3 98.6 98.6 117.6 2 85.9 85.9 69.9 69.9 69.9 69.9 58.7 58.7 58.7 104.9 111.3 111.3 111.3 143.0 143.0 146.1 2-1/2 98.6 98.6 82.6 82.6 82.6 82.6 69.9 69.9 69.9 124.0 130.3 130.3 130.3 165.1 165.1 168.4 120.7 120.7 101.6 101.6 101.6 101.6 95.3 92.2 92.2 136.7 149.4 149.4 149.4 168.4 174.8 196.9 3-1/2 133.4 133.4 114.3 114.3 104.8 104.8 104.8 104.8 - 161.9 165.1 161.9 161.9 190.5 187.3 149.4 149.4 127.0 127.0 120.7 120.7 120.7 117.6 117.6 174.8 181.1 177.8 193.8 206.5 209.6 235.0 4-1/2 165.1 165.1 139.7 139.7 134.9 134.9 134.9 134.9 177.8 196.9 193.7 209.6 238.1 231.8 3 4 - - - 5 177.8 177.8 155.7 155.7 147.6 147.6 147.6 143.0 143.0 196.9 215.9 212.9 241.3 247.7 254.0 279.4 6 209.6 209.6 182.6 182.6 174.8 174.8 174.8 171.5 171.5 222.3 251.0 247.7 266.7 289.1 282.7 317.5 8 263.7 257.3 233.4 233.4 225.6 225.6 222.3 215.9 215.9 279.4 308.1 304.8. 320.8 358.9 352.6 387.4 10 317.5 311.2 287.3 287.3 274.6 274.6 276.4 266.7 270.0 339.9 362.0 358.9 400.1 435.1 435.1 476.3 12 374.7 368.3 339.9 339.9 327.2 327.2 323.9 323.9 317.5 409.7 422.4 419.1 457.2 498.6 520.7 549.4 14 406.4 400.1 371.6 371.6 362.0 362.0 355.6 362.0 - 450.9 485.9 482.6 492.3 520.7 577.9 - 16 463.6 457.2 422.4 422.4 412.8 412.8 412.8 406.4 - 514.4 539.8 536.7 565.2 574.8 641.4 - 18 527.1 520.7 474.7 474.7 469.9 469.9 463.6 463.6 - 549.4 596.9 593.9 612.9 638.3 704.9 - 20 577.9 571.5 525.5 525.5 520.7 520.7 520.7 514.4 - 606.6 654.1 647.7 682.8 698.5 755.7 - 24 685.8 679.5 628.7 628.7 628.7 628.7 628.7 616.0 - 717.6 774.7 768.4 790.7 838.2 901.7 - DIMENSIONS IN MILLIMETERS. *For Style CGI - see Table 3 for Inner Ring dimensions. Gasket sizes 1/4” to 3” Class 300, 400 & 600 as well as sizes 1/2” to 2-1/2” Class 900 & 1500 are identical within their respective nominal pipe sizes, therefore inventories need not be duplicated. In accordance with ASME B16.20, Inner Rings are mandatory for the following flange designations (see Table 3). Class 900 - NPS 24 to 48 Class 1500 - NPS 12 to NPS 24 Class 2500 - NPS 4 to NPS 12 All PTFE filled gaskets All flexible graphite gaskets unless otherwise requested by the customer ASME B16.20 does not include dimensions for NPS 1/4, 3-1/2, or 4-1/2, or Class 400 Flanges up to NPS 3 and Class 900 Flanges up to NPS 2-1/2. YOUR GLOBAL GASKET PROVIDER 9