Learn about the 5 key flange gaskets types (used in the oil and gas industry): non-asbestos gaskets full and raised face (used for low-pressure, low-temperature and non-critical applications), spiral wound gaskets (for higher temperature and pressure oil and gas applications), Ring joint gaskets style R, RX, BX (for RTJ flange faces), Kammprofile and Jacketed gaskets. The article describes the scope of each type of gasket, the dimensions to ASME B16.20 and ASME B16.21, the materials and give some indications to select the right gasket for piping applications.
NON-ASBESTOS GASKET
Non-asbestos gaskets are the simplest type of gasket for flanges and are produced by cutting graphite, organic or inorganic non asbestos sheets into shape (generally, with water jet cutting machines). This type of gaskets for flanges suits low pressure, low temperature, and non-critical piping and plumbing applications.
The two main types of non-asbestos gaskets are the “full face” (FF) for FF flanges and the “flat ring” type for raised face flanges (RF).
Non-asbestos gaskets have fully replaced asbestos gaskets for decades as studies demonstrated the risks (for human health) associated with the production, use, and disposal of asbestos materials. The ASME B16.21 specification covers non-asbestos sheet gaskets (types, sheet materials, dimensions, dimensional tolerances, and marking requirements).

NON-ASBESTOS GASKET MATERIALS
The most common materials used to manufacture compressed fiber gaskets are aramid fibers (Kevlar), glass fibers, elastomers, Teflon (PTFE), graphite, neoprene mixed with various binder materials (the most common binder is NBR, i.e. Buna-N):
- Aramid NBR binder
- carbon graphite reinforced
- glass reinforced (steam service gasket)
- PTFE bi-axially oriented (silica filler)
- SBR (styrene-butadiene)
- CR-chloroprene (Neoprene)
- EPDM gasket (ethylene propylene)
- fluorocarbon (Viton)
- graphite
- BUNA-n-rubber (nitrile, NBR gasket)
- chlorosulfonated polyethylene (Hypalon gasket)
- aramid + SBR binder (premium type gasket)
- graphite + ss316/316l insert
- PTFE biaxially oriented (with hollow glass microsphere) blue
- PTFE biaxially oriented (pigment-free)-gray
- expanded PTFE gasket
- PTFE joint sealant
- PTFE envelope slit type
- PTFE envelope milled type
- PTFE envelope formed type
- MICA sheet
- ceramic fiber
Non-asbestos gaskets can also be coated with graphite, for non-stick and steam resistance, mixed with PTFE for excellent chemical resistance, or with EPDM for potable water applications.
NON-ASBESTOS GASKET DIMENSIONS
Soft Gaskets for ASME B16.5 Flanges
Non-asbestos gaskets dimensions (for ASME B16.5 flanges), in millimeters
NPS | d1 (ID) |
d2 (GASKET OUTSIDE DIAMETER) | ||||
Class 150 | Class 300 | Class 400 | Class 600 | Class 900 | ||
1/2 | 21 | 48 | 54 | 54 | 54 | 64 |
3/4 | 27 | 57 | 67 | 67 | 67 | 70 |
1 | 33 | 67 | 73 | 73 | 73 | 79 |
1¼ | 42 | 76 | 83 | 83 | 83 | 89 |
1½ | 48 | 86 | 95 | 95 | 95 | 98 |
2 | 60 | 105 | 111 | 111 | 111 | 143 |
2½ | 73 | 124 | 130 | 130 | 130.2 | 165 |
3 | 89 | 137 | 149 | 149 | 149 | 168 |
3½ | 102 | 162 | 165 | 162 | 162 | … |
4 | 114 | 175 | 181 | 178 | 194 | 206 |
5 | 141 | 197 | 216 | 213 | 241 | 248 |
6 | 168 | 222 | 251 | 248 | 267 | 289 |
8 | 219 | 279 | 308 | 305 | 321 | 359 |
10 | 273 | 340 | 362 | 359 | 400 | 435 |
12 | 324 | 410 | 422 | 419 | 457 | 498 |
14 | 356 | 451 | 486 | 483 | 492 | 521 |
16 | 406 | 514 | 540 | 537 | 565 | 575 |
18 | 457 | 549 | 597 | 594 | 613 | 638 |
20 | 508 | 606 | 654 | 648 | 683 | 699 |
24 | 610 | 718 | 775 | 768 | 791 | 838 |
All values in millimeters
Soft Gaskets for ASME B16.47 – Series A Flanges
Non-asbestos gaskets dimensions (for ASME B16.47 series A flanges), in millimeters
NPS | d1 (ID) | d2 (GASKET OUTSIDE DIAMETER) | |||
Class 150 | Class 300 | Class 400 | Class 600 | ||
26 | 660 | 775 | 835 | 832 | 867 |
28 | 711 | 832 | 899 | 892 | 914 |
30 | 762 | 883 | 953 | 946 | 972 |
32 | 813 | 940 | 1006 | 1003 | 1022 |
34 | 864 | 991 | 1057 | 1054 | 1073 |
36 | 914 | 1048 | 1118 | 1118 | 1130 |
38 | 965 | 1111 | 1054 | 1073 | 1105 |
40 | 1016 | 1162 | 1114 | 1127 | 1156 |
42 | 1067 | 1219 | 1165 | 1178 | 1219 |
44 | 1118 | 1276 | 1219 | 1232 | 1270 |
46 | 1168 | 1327 | 1273 | 1289 | 1327 |
48 | 1219 | 1384 | 1324 | 1346 | 1391 |
50 | 1270 | 1435 | 1378 | 1403 | 1448 |
52 | 1321 | 1492 | 1429 | 1454 | 1499 |
54 | 1372 | 1549 | 1492 | 1518 | 1556 |
56 | 1422 | 1607 | 1543 | 1568 | 1613 |
58 | 1473 | 1664 | 1594 | 1619 | 1664 |
60 | 1524 | 1715 | 1645 | 1683 | 1721 |
All values in millimeters
Soft Gaskets for ASME B16.47 – Series B Flanges
Non-asbestos gaskets dimensions (for ASME B16.47 series B flanges), in millimeters
NPS | d1 (ID) | d2 (GASKET OUTSIDE DIAMETER) | |||
Class 150 | Class 300 | Class 400 | Class 600 | ||
26 | 660 | 725 | 772 | 746 | 765 |
28 | 711 | 776 | 826 | 800 | 819 |
30 | 762 | 827 | 886 | 857 | 879 |
32 | 813 | 881 | 940 | 911 | 933 |
34 | 864 | 935 | 994 | 962 | 997 |
36 | 914 | 987 | 1048 | 1022 | 1048 |
38 | 965 | 1045 | 1099 | … | … |
40 | 1016 | 1095 | 1149 | … | … |
42 | 1067 | 1146 | 1200 | … | … |
44 | 1118 | 1197 | 1251 | … | … |
46 | 1168 | 1256 | 1318 | … | … |
48 | 1219 | 1307 | 1368 | … | … |
50 | 1270 | 1357 | 1419 | … | … |
52 | 1321 | 1408 | 1470 | … | … |
54 | 1372 | 1464 | 1530 | … | … |
56 | 1422 | 1514 | 1594 | … | … |
58 | 1473 | 1580 | 1656 | … | … |
60 | 1524 | 1630 | 1705 | … | … |
All values in millimeters. Dimensional tolerances:
- For outside diameter NPS 12 and smaller: +0 / -1.5 mm.; NPS 14 and larger: +0 / -3.0 mm.
- For inside diameter NPS 12 and smaller: ± 1.5 mm; NPS 14 and larger: ± 3.0 mm
SPIRAL WOUND GASKET
A Spiral wound gasket for flanges feature a metal sealing element filled with graphite, PTFE, ceramic fibers and, non-asbestos fibers (fillers). For this reason, spiral wound gaskets are classified as “semi-metallic” gaskets.
The metal component of the spiral wound gasket provides strength to the seal, whereas the fillers enhance the gasket’s conformability and resilience. Inner and outer rings can be added to the core sealing element to facilitate the installation and enhance the pressure rating. Spiral wound gaskets with graphite fillers are the most commonly sold type.
Flexitallic USA introduced spiral wound gaskets in the petrochemical industry back in 1912 to cope with an increasing demand for leak-proof seals in applications with higher and higher (and fluctuating) temperatures and pressures. Other reputable spiral wound gasket manufacturers are Garlock and Lamons.
Indeed, a spiral wound gasket is designed to withstand, better than other types of flange gaskets, the mechanical stress generated by high temperature and pressure applications. Spiral wound gasket application range, therefore, from oil and gas to power generation.
The diameter of a spiral wound gasket may range between a few mm up to 5.000 mm, and the spiral wound gasket thicknesses range from 3.2, 4.5, 6.4, to 7.2 mm.
A Spiral wound gasket may be ordered in different shapes, such as oblong, rectangular, oval, pear and diamond.
ASME B16.20 is the spiral wound gasket specification.
The round type is, of course, the standard shape for the raised face (RF), male-and-female (M&F), and tongue-and-groove flanges (T&G) for petrochemical applications.
SPIRAL WOUND GASKET TYPES
A few different types of spiral wound gaskets exist, depending on:
- the number of rings (outer and inner)
- the materials of the inner and the outer ring of the gasket
- Type 00: Spiral Wound Gasket without rings: they are used for tongue and groove, male and female flanges.
- Type 01: Spiral Wound Gasket with inner ring: they are used for male and female or special flange types.
- Type 10: Spiral Wound Gasket with outer ring: they are used for raised face flanges.
- Type 101: Spiral Wound Gasket with inner and outer rings: they are used for raised face flanges.
- Special Section: Spiral Wound Gasket with special rings: they are used for special flanges and special usage.
Each manufacturer, of course, has specific codes to designate the different spiral wound gasket types, but the typical designs are recurring regardless of the producer.
The image shows how the different spiral wound gasket types used for flanged joints in piping applications:
SPIRAL WOUND GASKET MATERIALS
Spiral Winding Materials
The sealing element of a spiral wound gasket is produced by interleaving plies of alternating metal winding strip combined with a filler material. The formed metal strip in the key sealing element of this type of semi-metallic gasket.
The most common winding materials are:
- SS 304L
- SS 316L
- SS 321
- Titanium
- Nickel
- Nickel alloys
- Duplex
Filler Materials
Filler materials are used to enhance the conformability and the resilience of a spiral wound gasket. The most used filler material is graphite, however, other filler materials may be used depending on the application:
- Graphite
- PTFE
- Ceramic fibers
- Non-asbestos
Inner and Outer Rings Materials
The inner and the outer rings of a spiral wound gasket may be the same material of the winding core or a different one.
Solid inner rings are required by the ASME B16.20 specification for flanges with pressure rating 900# NPS 24 and larger, 1500# NPS 12 and larger, pressure class 2500#, NPS 4 and larger.
The inner ring improves the pressure rating of the spiral wound gasket, as it provides additional compression to the flanged joint and provides a heat and corrosion barrier protecting the gasket windings and the flanges from erosion.
MECHANICAL PROPERTIES
Spiral Wound Gasket Material (Commercial Name) |
DIN SPECIFICATION |
DIN MATERIAL NR. |
AISI & UNS |
B.S & ASTM |
HARDNESS HV 10 |
TEMPERATURE RANGE in C° | VOLUMETRIC MASS [G/CM3] | |
MIN. | MAX. | |||||||
Soft Iron (Armco) | – | 1.1003 | – | – | 90 – 100 | -60 | 500 | 7.85 |
Steel (LCS) | RSt.37.2 | 1.0038 | – | – | 100 – 130 | -40 | 500 | 7.85 |
Stainless Steel 304 | X5CrNi 18 | 1.4301 | 304 | 304S15/16/31 | 130 – 180 | -250 | 550 | 7,9 |
Stainless Steel 304 L | X2CrNi 189 | 1.4306 | 304L | 304S11 | 130 – 190 | -250 | 550 | 7,9 |
Stainless Steel 309 | X15CrNiMo 2012 | 1.4828 | 309 | 309S24 | 130 – 190 | -100 | 1000 | 7,9 |
Stainless Steel 316 | X5CrNiMo 1810 | 1.4401 | 316 | 316S31/33 | 130 – 180 | -100 | 550 | 7,9 |
Stainless Steel 316 L | X2CrNiMo 1810 | 1.4404 | 316L | 316S11/13 | 130 – 190 | -100 | 550 | 7,9 |
Stainless Steel 316 Ti | X10CrNiMoTi 1810 | 1.4571 | 316Ti | 320S31 | 130 – 190 | -100 | 550 | 7,8 |
Stainless Steel 321 | X10CrNiTi 189 | 1.4541 | 321 | 321S12/49/87 | 130 – 190 | -250 | 550 | 7,9 |
Stainless Steel 347 | X10CrNiNb 189 | 1.4550 | 347 | 347S31 | 130 – 190 | -250 | 550 | 7,9 |
Nickel 200 | Ni 99.2 | 2,4066 | NO2200 | 3072-76 NA11 | 90 – 120 | -250 | 600 | 8,9 |
Monel 400 | NiCu 30 Fe | 2.4360 | NO4400 | 3072-76 NA13 | 110 – 150 | -125 | 600 | 8,8 |
Inconel 600 | NiCr 15 Fe | 2.4816 | NO6600 | 3072-76 NA14 | 120 – 180 | -100 | 950 | 8,4 |
Incoloy 800 | X10NiCrAITi 3220 | 1.4876 | NO8800 | 3072-76 NA15 | 140 – 220 | -100 | 850 | 8,4 |
Incoloy 825 | NiCR 21 Mo | 2.4858 | NO8825 | 3072-76 NA 16 | 120 – 180 | -100 | 450 | 8,14 |
Hastelloy B2 | NMo 28 | 2.4617 | N10665 | – | 170 – 230 | -200 | 450 | 9,2 |
Hastelloy C276 | ‘NiMo 16Cr15W | 2.4819 | N10276 | – | 170 – 230 | -200 | 450 | 8.9 |
Titanium | Ti 99,8 | 3.7025 | – | – | 110 – 140 | -250 | 500 | 4,5 |
SPIRAL WOUND GASKET COLORS
Spiral wound gaskets made with different windings and filler materials are easy to spot, as each combination is designated by the application of color codes (the main color designates the winding materials, the stripes indicate the type of filler):
- Metallic winding materials: the metallic winding material is designated by a solid color identification around the outside edge of the centering, as shown in the image below
- Non-metallic filler color coding: the gasket filler materials are designated by a number of stripes placed at equal distances around the edge of the centering ring
Color Codes for Winding Materials
Metallic Winding Material for Spiral Wound Gasket | Abbreviated Winding Material Name |
Color Code |
Carbon steel | CRS | Silver |
304 SS | 304 | Yellow |
304 L SS | 304 L | No color |
309 SS | 309 | No color |
316 L SS | 316 L | Green |
347 SS | 347 | Blue |
321 SS | 321 | Turquoise |
Monel 400 | MON | Orange |
Nickel 200 | NI | Red |
Titanium | TI | Purple |
Hastelloy B | HAST B | Brown |
Hastelloy C | HAST C | Beige |
Color Codes for Filler Materials
Polytetrafluoroethylene | PTFE | White stripe |
Mica-graphite | Manufacturer’s designation | Pink stripe |
Flexible graphite | F.G. | Gray stripe |
Ceramic | CER | Light green stripe |
Inconel 600 | Inconel 600 | Gold |
Inconel 625 | Inconel 625 | Gold |
Incoloy 800 | Incoloy 800 H / HT | White |
Incoloy 825 | Incoloy 825 | White |
SPIRAL WOUND GASKET MARKING
The illustration shows the typical marking of spiral wound gaskets:
SPIRAL WOUND GASKETS DIMENSIONS
Class 150
Dimensions of class 150 spiral wound gaskets for ASME B16.5 (in mm.)

NPS | Inner Ring | Sealing Element | Outer Ring | |
Inside Diameter (d1) | Inside Diameter (d2) | Outside Diameter(d3) | Outside Diameter (d4) | |
1/2 | 14.2 | 19.1 | 31.8 | 47.8 |
3/4 | 20.6 | 25.4 | 39.6 | 57.2 |
1 | 26.9 | 31.8 | 47.8 | 66.8 |
1¼ | 38.1 | 47.8 | 60.5 | 76.2 |
1½ | 44.5 | 54.1 | 69.9 | 85.9 |
2 | 55.6 | 69.9 | 85.9 | 104.9 |
2½ | 66.5 | 82.6 | 98.6 | 124 |
3 | 81 | 101.6 | 120.7 | 136.7 |
4 | 106.4 | 127 | 149.4 | 174.8 |
5 | 131.8 | 155.7 | 177.8 | 196.9 |
6 | 157.2 | 182.6 | 209.6 | 222.3 |
8 | 215.9 | 233.4 | 263.7 | 279.4 |
10 | 268.2 | 287.3 | 317.5 | 339.9 |
12 | 317.5 | 339.9 | 374.7 | 409.7 |
14 | 349.3 | 371.6 | 406.4 | 450.9 |
16 | 400.1 | 422.4 | 463.6 | 514.4 |
18 | 449.3 | 474.7 | 527.1 | 549.4 |
20 | 500.1 | 525.5 | 577.9 | 606.6 |
24 | 603.3 | 628.7 | 685.8 | 717.6 |
NOTES: • All dimensions are in millimeters • Spiral Wound gasket with Inner – and Outer ring • d1 = Inside diameter Inner ring. • d2 = Inside diameter sealing element when no Inner ring is used. • d3 = Outside diameter of sealing element. • d4 = Outside diameter of an Outer ring
The thickness of inner and outer ring: 2.97 mm – 3.33 mm. • Thickness sealing element: 4.45 mm. • Tolerance Outside diameter for NPS 1/2 through NPS 8 is ± 0.8 mm; for NPS 10 through NPS 24 tolerance is + 1.5 mm – 0.8 mm. • There is no class 400 flanges NPS 1/2 thru NPS 3 (use Class 600), class 900 flanges NPS 1/2 thru NPS 2½ (use Class 1500), or class 2500 flanges NPS 14 or larger.
Class 300
Dimensions of class 300 spiral wound gaskets for ASME B16.5 (in mm.)

NPS | Inner Ring | Sealing Element | Outer Ring | |
Inside Diameter (d1) | Inside Diameter (d2) | Outside Diameter (d3) | Outside Diameter (d4) | |
1/2 | 14.2 | 19.1 | 31.8 | 54.1 |
3/4 | 20.6 | 25.4 | 39.6 | 66.8 |
1 | 26.9 | 31.8 | 47.8 | 73.2 |
1¼ | 38.1 | 47.8 | 60.5 | 82.6 |
1½ | 44.5 | 54.1 | 69.9 | 95.3 |
2 | 55.6 | 69.9 | 85.9 | 111.3 |
2½ | 66.5 | 82.6 | 98.6 | 130.3 |
3 | 81 | 101.6 | 120.7 | 149.4 |
4 | 106.4 | 127 | 149.4 | 181.1 |
5 | 131.8 | 155.7 | 177.8 | 215.9 |
6 | 157.2 | 182.6 | 209.6 | 251 |
8 | 215.9 | 233.4 | 263.7 | 308.1 |
10 | 268.2 | 287.3 | 317.5 | 362 |
12 | 317.5 | 339.9 | 374.7 | 422.4 |
14 | 349.3 | 371.6 | 406.4 | 485.9 |
16 | 400.1 | 422.4 | 463.6 | 539.8 |
18 | 449.3 | 474.7 | 527.1 | 596.9 |
20 | 500.1 | 525.6 | 577.9 | 654.1 |
24 | 603.3 | 628.7 | 685.8 | 774.7 |
NOTES: • All dimensions are in millimeters • Spiral Wound gasket with Inner – and Outer ring • d1 = Inside diameter Inner ring. • d2 = Inside diameter sealing element when no Inner ring is used. • d3 = Outside diameter of sealing element. • d4 = Outside diameter of an Outer ring
The thickness of inner and outer ring: 2.97 mm – 3.33 mm. • Thickness sealing element: 4.45 mm. • Tolerance Outside diameter for NPS 1/2 through NPS 8 is ± 0.8 mm; for NPS 10 through NPS 24 tolerance is + 1.5 mm – 0.8 mm. • There is no class 400 flanges NPS 1/2 thru NPS 3 (use Class 600), class 900 flanges NPS 1/2 thru NPS 2½ (use Class 1500), or class 2500 flanges NPS 14 or larger.
Class 400
Dimensions of class 400 spiral wound gaskets for ASME B16.5 (in mm.)

NPS | Inner Ring | Sealing Element | Outer Ring | |
Inside Diameter (d1) | Inside Diameter (d2) | Outside Diameter (d3) | Outside Diameter (d4) | |
1/2 | 14.2 | 19.1 | 31.8 | 54.1 |
3/4 | 20.6 | 25.4 | 39.6 | 66.8 |
1 | 26.9 | 31.8 | 47.8 | 73.2 |
1¼ | 38.1 | 47.8 | 60.5 | 82.6 |
1½ | 44.5 | 54.1 | 69.9 | 95.3 |
2 | 55.6 | 69.9 | 85.9 | 111.3 |
2½ | 66.5 | 82.6 | 98.6 | 130.3 |
3 | 81 | 101.6 | 120.7 | 149.4 |
4 | 102.6 | 120.7 | 149.4 | 177.8 |
5 | 128.3 | 147.6 | 177.8 | 212.9 |
6 | 154.9 | 174.8 | 209.6 | 247.7 |
8 | 205.7 | 225.6 | 263.7 | 304.8 |
10 | 255.3 | 274.6 | 317.5 | 358.9 |
12 | 307.3 | 327.2 | 374.7 | 419.1 |
14 | 342.9 | 362 | 406.4 | 482.6 |
16 | 389.9 | 412.8 | 463.6 | 536.7 |
18 | 438.2 | 469.9 | 527.1 | 593.9 |
20 | 489 | 520.7 | 577.9 | 647.7 |
24 | 590.6 | 628.7 | 685.8 | 768.4 |
NOTES: • All dimensions are in millimeters • Spiral Wound gasket with Inner – and Outer ring • d1 = Inside diameter Inner ring. • d2 = Inside diameter sealing element when no Inner ring is used. • d3 = Outside diameter of sealing element. • d4 = Outside diameter of an Outer ring
The thickness of inner and outer ring: 2.97 mm – 3.33 mm. • Thickness sealing element: 4.45 mm. • Tolerance Outside diameter for NPS 1/2 through NPS 8 is ± 0.8 mm; for NPS 10 through NPS 24 tolerance is + 1.5 mm – 0.8 mm. • There is no class 400 flanges NPS 1/2 thru NPS 3 (use Class 600), class 900 flanges NPS 1/2 thru NPS 2½ (use Class 1500), or class 2500 flanges NPS 14 or larger.
Class 600
Dimensions of class 600 spiral wound gaskets for ASME B16.5 (in mm.)

NPS | Inner Ring | Sealing Element | Outer Ring | |
Inside Diameter (d1) | Inside Diameter (d2) | Outside Diameter (d3) | Outside Diameter (d4) | |
1/2 | 14.2 | 19.1 | 31.8 | 54.1 |
3/4 | 20.6 | 25.4 | 39.6 | 66.8 |
1 | 26.9 | 31.8 | 47.8 | 73.2 |
1¼ | 38.1 | 47.8 | 60.5 | 82.6 |
1½ | 44.5 | 54.1 | 69.9 | 95.3 |
2 | 55.6 | 69.9 | 85.9 | 111.3 |
2½ | 66.5 | 82.6 | 98.6 | 130.3 |
3 | 78.7 | 101.6 | 120.7 | 149.4 |
4 | 102.6 | 120.7 | 149.4 | 193.8 |
5 | 128.3 | 147.6 | 177.8 | 241.3 |
6 | 154.9 | 174.8 | 209.6 | 266.7 |
8 | 205.7 | 225.6 | 263.7 | 320.8 |
10 | 255.3 | 274.6 | 317.5 | 400.1 |
12 | 307.3 | 327.2 | 374.7 | 457.2 |
14 | 342.9 | 362 | 406.4 | 492.3 |
16 | 389.9 | 412.8 | 463.6 | 565.2 |
18 | 438.2 | 469.9 | 527.1 | 612.9 |
20 | 489 | 520.7 | 577.9 | 682.8 |
24 | 590.6 | 628.7 | 685.8 | 790.7 |
NOTES: • All dimensions are in millimeters • Spiral Wound gasket with Inner – and Outer ring • d1 = Inside diameter Inner ring. • d2 = Inside diameter sealing element when no Inner ring is used. • d3 = Outside diameter of sealing element. • d4 = Outside diameter of an Outer ring
The thickness of inner and outer ring: 2.97 mm – 3.33 mm. • Thickness sealing element: 4.45 mm. • Tolerance Outside diameter for NPS 1/2 through NPS 8 is ± 0.8 mm; for NPS 10 through NPS 24 tolerance is + 1.5 mm – 0.8 mm. • There is no class 400 flanges NPS 1/2 thru NPS 3 (use Class 600), class 900 flanges NPS 1/2 thru NPS 2½ (use Class 1500), or class 2500 flanges NPS 14 or larger.
Class 900
Dimensions of class 900 spiral wound gaskets for ASME B16.5 (in mm.)

NPS | Inner Ring | Sealing Element | Outer Ring | |
Inside Diameter (d1) | Inside Diameter (d2) | Outside Diameter(d3) | Outside Diameter (d4) | |
1/2 | 14.2 | 19.1 | 31.8 | 63.5 |
3/4 | 20.6 | 25.4 | 39.6 | 69.9 |
1 | 26.9 | 31.8 | 47.8 | 79.5 |
1¼ | 33.3 | 39.6 | 60.5 | 88.9 |
1½ | 41.4 | 47.8 | 69.9 | 98.6 |
2 | 52.3 | 58.7 | 85.9 | 143 |
2½ | 63.5 | 69.9 | 98.6 | 165.1 |
3 | 78.7 | 95.3 | 120.7 | 168.4 |
4 | 102.6 | 120.7 | 149.4 | 206.5 |
5 | 128.3 | 147.6 | 177.8 | 247.7 |
6 | 154.9 | 174.8 | 209.6 | 289.1 |
8 | 196.9 | 222.3 | 257.3 | 358.9 |
10 | 246.1 | 276.4 | 311.2 | 435.1 |
12 | 292.1 | 323.9 | 368.3 | 498.6 |
14 | 320.8 | 355.6 | 400.1 | 520.7 |
16 | 374.7 | 412.8 | 457.2 | 574.8 |
18 | 425.5 | 463.6 | 520.7 | 638.3 |
20 | 482.6 | 520.7 | 571.5 | 698.5 |
24 | 590.6 | 628.7 | 679.5 | 838.2 |
NOTES: • All dimensions are in millimeters • Spiral Wound gasket with Inner – and Outer ring • d1 = Inside diameter Inner ring. • d2 = Inside diameter sealing element when no Inner ring is used. • d3 = Outside diameter of sealing element. • d4 = Outside diameter of an Outer ring
The thickness of inner and outer ring: 2.97 mm – 3.33 mm. • Thickness sealing element: 4.45 mm. • Tolerance Outside diameter for NPS 1/2 through NPS 8 is ± 0.8 mm; for NPS 10 through NPS 24 tolerance is + 1.5 mm – 0.8 mm. • There is no class 400 flanges NPS 1/2 thru NPS 3 (use Class 600), class 900 flanges NPS 1/2 thru NPS 2½ (use Class 1500), or class 2500 flanges NPS 14 or larger.
Class 1500
Dimensions of class 1500 spiral wound gaskets for ASME B16.5 (in mm.)

NPS | Inner Ring | Sealing Element | Outer Ring | |
Inside Diameter (d1) | Inside Diameter (d2) | Outside Diameter(d3) | Outside Diameter (d4) | |
1/2 | 14.2 | 19.1 | 31.8 | 63.5 |
3/4 | 20.6 | 25.4 | 39.6 | 69.9 |
1 | 26.9 | 31.8 | 47.8 | 79.5 |
1¼ | 33.3 | 39.6 | 60.5 | 88.9 |
1½ | 41.4 | 47.8 | 69.9 | 98.6 |
2 | 52.3 | 58.7 | 85.9 | 143 |
2½ | 63.5 | 69.9 | 98.6 | 165.1 |
3 | 78.7 | 92.2 | 120.7 | 174.8 |
4 | 97.8 | 117.6 | 149.4 | 209.6 |
5 | 124.5 | 143 | 177.8 | 254 |
6 | 147.3 | 171.5 | 209.6 | 282.7 |
8 | 196.9 | 215.9 | 257.3 | 352.6 |
10 | 246.1 | 266.7 | 311.2 | 435.1 |
12 | 292.1 | 323.9 | 368.3 | 520.7 |
14 | 320.8 | 362 | 400.1 | 577.9 |
16 | 374.7 | 406.4 | 457.2 | 641.4 |
18 | 425.5 | 463.6 | 520.7 | 704.9 |
20 | 476.3 | 514.4 | 571.5 | 755.7 |
24 | 577.9 | 616 | 679.5 | 901.7 |
The thickness of inner and outer ring: 2.97 mm – 3.33 mm. • Thickness sealing element: 4.45 mm. • Tolerance Outside diameter for NPS 1/2 through NPS 8 is ± 0.8 mm; for NPS 10 through NPS 24 tolerance is + 1.5 mm – 0.8 mm. • There is no class 400 flanges NPS 1/2 thru NPS 3 (use Class 600), class 900 flanges NPS 1/2 thru NPS 2½ (use Class 1500), or class 2500 flanges NPS 14 or larger.
Class 2500
Dimensions of class 2500 spiral wound gaskets for ASME B16.5 (in mm.)

NPS | Inner Ring | Sealing Element | Outer Ring | |
Inside Diameter (d1) | Inside Diameter (d2) | Outside Diameter(d3) | Outside Diameter (d4) | |
1/2 | 14.2 | 19.1 | 31.8 | 69.9 |
3/4 | 20.6 | 25.4 | 39.6 | 76.2 |
1 | 26.9 | 31.8 | 47.8 | 85.9 |
1¼ | 33.3 | 39.6 | 60.5 | 104.9 |
1½ | 41.4 | 47.8 | 69.9 | 117.6 |
2 | 52.3 | 58.7 | 85.9 | 146 |
2½ | 63.5 | 69.9 | 98.6 | 168.4 |
3 | 78.7 | 92.2 | 120.7 | 196.9 |
4 | 97.8 | 117.6 | 149.4 | 235 |
5 | 124.5 | 143 | 177.8 | 279.4 |
6 | 147.3 | 171.5 | 209.6 | 317.5 |
8 | 196.9 | 215.9 | 257.3 | 387.4 |
10 | 246.1 | 270 | 311.2 | 476.3 |
12 | 292.1 | 317.5 | 368.3 | 549.4 |
NOTES: • All dimensions are in millimeters • Spiral Wound gasket with Inner – and Outer ring • d1 = Inside diameter Inner ring. • d2 = Inside diameter sealing element when no Inner ring is used. • d3 = Outside diameter of sealing element. • d4 = Outside diameter of an Outer ring
The thickness of inner and outer ring: 2.97 mm – 3.33 mm. • Thickness sealing element: 4.45 mm. • Tolerance Outside diameter for NPS 1/2 through NPS 8 is ± 0.8 mm; for NPS 10 through NPS 24 tolerance is + 1.5 mm – 0.8 mm. • There is no class 400 flanges NPS 1/2 thru NPS 3 (use Class 600), class 900 flanges NPS 1/2 thru NPS 2½ (use Class 1500), or class 2500 flanges NPS 14 or larger.
RING JOINT GASKETS R, RX, BX
A Ring Joint Gasket (RTJ) provides a strong and durable metal-to-metal seal between two mating RTJ flanges. As the flanges are bolted, the softer material of the ring joint gasket is “squeezed” into the flanges grooves (made of a harder material) and seals the connection very tightly. RTJ gaskets are available in three styles, R (oval, octagonal), RX, and BX.
Ring joint gaskets (RTJ) ensure a long lasting and strong seal for flanges, valves, piping spools and vessels at high pressure and temperatures (which are typical conditions for many petrochemical processes).
RTJ GASKETS TYPES
R Type Ring Joint Gasket (Oval and Octagonal)
“Style R” is the most common RTJ gasket type. R type ring joint gaskets are available in oval or octagonal cross-section and manufactured according to API 6A and ASME B16.20 to suit API 6B and ASME/ANSI B16.5 flanges.
This type of RTJ gasket is machined to tight manufacturing tolerances to ensure correct installation with standard ASME B16.5 and API 6B ring joint faced flanges. “R style” oval and octagonal RTJ gaskets can seal pressures up to 6.250 psi by ASME B16.20 and up to 5.000 psi according to the API 6A pressure ratings.
Type R RTJ gaskets are frequently used for valves covers.
Style RX RTJ Gasket
The RX type RTJ gasket is manufactured according to API 6A and ASME B16.20 to suit API 6B and ASME/ANSI B16.5 flanges.
The RX is a pressure energized version of the R octagonal gasket and fits the R type flat-bottomed groove.
The RX has an increased height and utilizes the internal system pressure to energize and improve the seal as internal pressure increases.
Some RX sizes have a pressure relief hole to equalize pressure on both sides of the sealing faces.
Style BX RTJ Gasket
The BX type RTJ gaskets are manufactured according to API 6A and are suitable for use in high-pressure API 6BX flanges.
The gaskets form a metal to metal seal on assembly and the efficiency improves as internal pressure increases.
All BX sizes have a pressure relief hole to equalize pressure across sealing faces.
RTJ GASKET MATERIALS
In case a harder material for the ring type joint is used, the groove of the flange would be damaged as the flanges are tightened (the hardness values for ring joint gaskets are given below).
Types of Materials for Ring Joint Gaskets
RTJ GASKET MATERIAL | RING ID | ASTM GRADE | DIN GRADE | WKSTOFF NUMBER | AISI GRADE |
BS GRADE |
OTHER SPECS |
Soft Iron | D | 1.1003 / 1.0335 | Aramco / StW24 | ||||
LCS | S | 1.1003 / 1.0335 | Aramco / StW24 | ||||
CS360 LT | CS360LT | A516 Gr70 | |||||
4140 | 4140 | UNS G41400 | 42CrMo4 | 1.7225 | 4140 | ||
F5 | F5 | UNS K42544 | 12CrMo195 | 1.7362 | 5Cr 1/2Mo | ||
SS304 | S304 | S30400 | X5CrNi 18 9 | 1.4301 | 304 | 304S15 | |
SS304L | S304L | S30403 | X2CrNi 18 9 | 1.4306 | 304L | 304SS12 | |
SS309 | S309 | S30900 | X15CrNiSi2012 | 1.4828 | 309 | 309S24 | |
SS310 | S310 | S31008 | XX15CrNiSi2520 | 1.4841 | 310 | 310S24 | |
SS316 | S316 | S31600 | X5CrNiMo18 10 | 1.4401 | 316 | 316S16 | |
SS316L | S316L | S31603 | X2CrNiMo18 10 | 1.4404 | 316L | 316S11/316S12 | |
SS316L UREA | S316UG | S31603 | X2CrNiMo 18 14 3 | 1.4435 | |||
SS316Ti | S316Ti | S31635 | X10CrNiMoTi1810 | 1.4571 | 316Ti | 320S31/320S17 | |
SS321 | S321 | S32100 | X10CrNiTi18 9 | 1.4541 | 321 | 321S12 | |
SS347 | S347 | S34700 | X10CrNiNb 18 9 | 1.455 | 347 | 347S51 | |
SS410 | S410 | S41000 | X10Cr13 | 1.4006 | 410 | 410S21 | |
Monel 400 | Monel400 | N04400 | NiCu30Fe | 2.436 | |||
Inconel 600 | INC600 | N06600 | NiCr15Fe | 2.4816 | |||
Inconel 625 | INC625 | N06625 | NiCr22Mo9Nb | 2.4856 | |||
Inconel 718 | INC718 | N07718 | |||||
Incoloy 800 | INC800 | N08800 | X5NiCrAlTi31-20 | 1.4958 | |||
Incoloy 800H | INC800H | N08810 | 1.4958 | ||||
Incoloy 825 | INC825 | N08825 | NiCr21Mo | 2.4858 | |||
904L | 904L | N08904 | X1NiCrMoCu25-20-5 | 1.4539 | |||
F51 | F51 | S31803 | X2CrNiMoN22-5-3 | 1.4462 | 2205 /Duplex | ||
F53 | F53 | S32750 | X2CrNiMoN25-7-4 | 1.441 | |||
F55 | F55 | S32760 | X2CrNiMoCuWN 25 7 4 | 1.4501 | Zeron 100 | ||
F60 | F60 | S32205 | Duplex | ||||
Titanium | Ti | R 50400 | 3.7035 | ||||
17-4PH | 17-4PH | S17400 | 1.4542 | 630 | |||
S254 | S254 | S31254 | X1CrNiMoCuN20-18-7 | 1.4547 | F44 / 6Mo | ||
C276 | C276 | N10276 | NiMo16Cr15W | 2.4819 | Hastelloy | ||
Alloy 28 | Alloy28 | N08028 | X1 NiCrMoCuN 31 27 4 | 1.4563 | SANICRO 28 |
Mechanical Properties Ring Joint Gaskets Materials
Maximum Hardness of RTJ Gaskets | |||
RTJ Gasket Material |
Brinell | HRB | ID |
Soft Iron-S |
90 | 56 | D |
Low Carbon Steel |
120 | 68 | S |
4 – 6% Chrome |
130 | 72 | F5 |
SS 304 Stainless Steel |
160 | 83 | S304 |
SS 316 Stainless Steel |
160 | 83 | S316 |
SS 347 Stainless Steel |
160 | 83 | S347 |
SS 410 Stainless Steel |
170 | 96 | S410 |
RTJ GASKET DIMENSIONS (ASME B16.20)
Style R Ring Joint Gaskets Dimensions (for ASME B16.5 flanges)
RTJ GASKET RING NUMBER | Diameter P | Width A | Height | Oct C | Oct R1 | NPS / CLASS | |
Oval B | Oct H | ||||||
R 11 | 34.14 | 6.35 | 11.2 | 9.7 | 4.32 | 1.5 | 1/2 300 / 600 |
R 12 | 39.7 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 1/2 900 / 1500 |
R 13 | 42.88 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 3/4 300 / 600 1/2 2500 |
R 14 | 44.45 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 3/4 900 / 1500 |
R 15 | 47.63 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 1 150 |
R 16 | 50.8 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 1 300 / 1500 3/4 2500 |
R 17 | 57.15 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 1¼ 150 |
R 18 | 60.33 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 1¼ 300 / 1500 1 2500 |
R 19 | 65.1 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 1½ 150 |
R 20 | 68.28 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 1½ 300 / 1500 |
R 21 | 72.24 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 1¼ 2500 |
R 22 | 82.55 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 2 150 |
R 23 | 82.55 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 2 300 600 1½ 2500 |
R 24 | 95.25 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 2 900 / 1500 |
R 25 | 101.6 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 2½ 150 |
R 26 | 101.6 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 2½ 300/ 600 2 2500 |
R 27 | 107.95 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 2½ 900 / 1500 |
R 28 | 111.13 | 12.7 | 19.1 | 17.5 | 8.66 | 1.5 | 2½ 2500 |
R 29 | 114.3 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 3 150 |
R 30 * |
117.48 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 3 300 / 600 |
R 31 | 123.83 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 3 300 / 900 |
R 32 | 127 | 12.7 | 19.1 | 17.5 | 8.66 | 1.5 | 3 2500 |
R 33 | 131.78 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 3½ 150 |
R 34 | 131.78 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 3½ 300 / 600 |
R 35 | 136.53 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 3 1500 |
R 36 | 149.23 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 4 150 |
R 37 | 149.23 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 4 300 / 900 |
R 38 | 157.18 | 15.88 | 22.4 | 20.6 | 10.49 | 1.5 | 4 2500 |
R 39 | 161.93 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 4 1500 |
R 40 | 171.45 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 5 150 |
R 41 | 180.98 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 5 300 / 900 |
R 42 | 190.5 | 19.05 | 25.4 | 23.9 | 12.32 | 1.5 | 5 2500 |
R 43 | 193.68 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 6 150 |
R 44 | 193.68 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 5 1500 |
R 45 | 211.15 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 6 300 / 900 |
R 46 | 211.15 | 12.7 | 19.1 | 17.5 | 8.66 | 1.5 | 6 1500 |
R 47 | 228.6 | 19.05 | 25.4 | 23.9 | 12.32 | 1.5 | 6 2500 |
R 48 | 247.65 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 8 150 |
R 49 | 269.88 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 8 300 / 900 |
R 50 | 269.88 | 15.88 | 22.4 | 20.6 | 10.49 | 1.5 | 8 1500 |
R 51 | 279.4 | 22.23 | 28.7 | 26.9 | 14.81 | 1.5 | 8 2500 |
R 52 | 304.8 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 10 150 |
R 53 | 323.85 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 10 300 900 |
R 54 | 323.85 | 15.88 | 22.4 | 20.6 | 10.49 | 1.5 | 10 1500 |
R 55 | 342.9 | 28.58 | 36.6 | 35.1 | 19.81 | 2.3 | 10 2500 |
R 56 | 381 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 12 150 |
R 57 | 381 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 12 300 900 |
R 58 | 381 | 22.23 | 28.7 | 26.9 | 14.81 | 1.5 | 12 1500 |
R 59 | 396.88 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 14 150 |
R 60 | 406.4 | 31.75 | 39.6 | 38.1 | 22.33 | 2.3 | 12 2500 |
R 61 | 419.1 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 14 300 600 |
R 62 | 419.1 | 15.88 | 22.4 | 20.6 | 10.49 | 1.5 | 14 900 |
R 63 | 419.1 | 25.4 | 33.3 | 31.8 | 17.3 | 2.3 | 14 1500 |
R 64 | 454.03 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 16 150 |
R 65 | 469.9 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 16 300 600 |
R 66 | 469.9 | 15.88 | 22.4 | 20.6 | 10.49 | 1.5 | 16 900 |
R 67 | 469.9 | 28.58 | 36.6 | 35.1 | 19.81 | 2.3 | 16 1500 |
R 68 | 517.53 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 18 150 |
R 69 | 533.4 | 11.13 | 17.5 | 16 | 7.75 | 1.5 | 18 300 600 |
R 70 | 533.4 | 19.05 | 25.4 | 23.9 | 12.32 | 1.5 | 18 900 |
R 71 | 533.4 | 28.58 | 36.6 | 35.1 | 19.81 | 2.3 | 18 1500 |
R 72 | 558.8 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 20 150 |
R 73 | 584.2 | 12.7 | 19.1 | 17.5 | 8.66 | 1.5 | 20 300 600 |
R 74 | 584.2 | 19.05 | 25.4 | 23.9 | 12.32 | 1.5 | 20 900 |
R 75 | 584.2 | 31.75 | 39.6 | 38.1 | 22.33 | 2.3 | 20 1500 |
R 76 | 673.1 | 7.95 | 14.2 | 12.7 | 5.23 | 1.5 | 24 150 |
R 77 | 692.15 | 15.88 | 22.4 | 20.6 | 10.49 | 1.5 | 24 300 600 |
R 78 | 692.15 | 25.4 | 33.3 | 31.8 | 17.3 | 2.3 | 24 900 |
R 79 | 692.15 | 34.93 | 44.5 | 41.4 | 24.82 | 2.3 | 24 1500 |
Style R Ring Joint Gaskets Dimensions (for ASME B16.47 Series A flanges)
RTJ GASKET RING NUMBER | Dia P |
Width A |
Height | Oct C |
Oct R1 |
NPS CLASS |
|
Oval B |
Oct H |
||||||
R 93 | 749.3 | 19.05 | … | 23.9 | 12.32 | 1.5 | 26 300 600 |
R 94 | 800.1 | 19.05 | … | 23.9 | 12.32 | 1.5 | 28 300 600 |
R 95 | 857.25 | 19.05 | … | 23.9 | 12.32 | 1.5 | 30 300 600 |
R 96 | 914.4 | 22.23 | … | 26.9 | 14.81 | 1.5 | 32 300 600 |
R 97 | 965.2 | 22.23 | … | 26.9 | 14.81 | 1.5 | 34 300 600 |
R 98 | 1022.35 | 22.23 | … | 26.9 | 14.81 | 1.5 | 36 300 600 |
R 100 | 749.3 | 28.58 | … | 35.1 | 19.81 | 2.3 | 26 900 |
R 101 | 800.1 | 31.75 | … | 38.1 | 22.33 | 2.3 | 28 900 |
R 102 | 857.25 | 31.75 | … | 38.1 | 22.33 | 2.3 | 30 900 |
R 103 | 914.4 | 31.75 | … | 38.1 | 22.33 | 2.3 | 32 900 |
R 104 | 965.2 | 34.93 | … | 41.4 | 24.82 | 2.3 | 34 900 |
R 105 | 1022.35 | 34.93 | … | 41.4 | 24.82 | 2.3 | 36 900 |
Style RX Ring Joint Gaskets Dimensions
RTJ GASKET RING NUMBER | 720-960 | 2900# | 3000# | 5000# | OD | HEIGHT | WIDTH | GASKET Wt. ( kg ) |
RX20 | 1 ½ | – | 1 ½ | 1 ½ | 76.2 | 19.05 | 8.74 | 0.24 |
RX23 | 2, 2 1/16 | – | 93.27 | 25.4 | 11.91 | 0.52 | ||
RX24 | – | – | 2, 2 1/16 | 2, 2 1/16 | 105.97 | 25.4 | 11.91 | 0.6 |
RX25 | – | – | – | 3 1/8 | 109.55 | 19.05 | 8.74 | 0.5 |
RX26 | 2 ½ , 2 9/16 | – | – | – | 111.91 | 25.4 | 11.91 | 0.64 |
RX27 | – | – | 2 ½, 2 9/16 | 2 ½, 2 9/16 | 118.26 | 25.4 | 11.91 | 0.68 |
RX31 | 3 , 3 1/8 | – | 3, 3 1/8 | 134.54 | 25.4 | 11.91 | 0.78 | |
RX35 | – | – | – | 3, 3 1/8 | 147.24 | 25.4 | 11.91 | 0.86 |
RX37 | 4 , 4 1/16 | – | 4, 4 1/16 | – | 159.94 | 25.4 | 11.91 | 0.95 |
RX39 | – | – | – | 4, 4 1/16 | 172.64 | 25.4 | 11.91 | 1.03 |
RX41 | 5, 5 1/8 | – | 5, 5 1/8 | – | 191.69 | 25.4 | 11.91 | 1.15 |
RX44 | – | – | – | 5, 5 1/8 | 204.39 | 25.4 | 11.91 | 1.23 |
RX45 | 6, 7 1/16 | – | 6, 7 1/16 | – | 221.84 | 25.4 | 11.91 | 1.34 |
RX46 | – | – | – | 6, 7 1/16 | 222.25 | 28.58 | 13.49 | 1.66 |
RX47 | – | – | – | 8 | 245.26 | 41.28 | 19.84 | 3.88 |
RX49 | 8, 9 | – | 8, 9 | 280.59 | 25.4 | 11.91 | 1.72 | |
RX50 | – | – | – | 8, 9 | 283.36 | 31.75 | 16.66 | 2.43 |
RX53 | 10, 11 | – | 10, 11 | 334.57 | 25.4 | 11.91 | 2.06 | |
RX54 | – | – | – | 10, 11 | 337.34 | 31.75 | 16.66 | 2.92 |
RX57 | 12, 13 5/8 | – | 12, 13 5/8 | 391.72 | 25.4 | 11.91 | 2.42 | |
RX63 | – | – | 14 | 441.73 | 50.8 | 27 | 11.96 | |
RX65 | 16, 16 3/4 | – | – | – | 480.62 | 25.4 | 11.91 | 3 |
RX66 | – | – | 16, 16 3/4 | – | 457.99 | 31.75 | 16.66 | 4.25 |
RX69 | 18 | – | 544.12 | 25.4 | 11.91 | 3.41 | ||
RX70 | – | – | 18 | – | 550.06 | 41.28 | 19.84 | 9.12 |
RX73 | 20, 21 1/4 | – | – | – | 596.11 | 31.75 | 13.49 | 5.27 |
RX74 | – | – | 20, 20 3/4 | – | 600.86 | 41.28 | 19.84 | 10.01 |
RX82 | – | 1 | – | – | 67.87 | 25.4 | 11.91 | 0.36 |
RX84 | – | 1 ½ | – | – | 74.22 | 25.4 | 11.91 | 0.4 |
RX85 | – | 2 | – | – | 90.09 | 25.4 | 13.49 | 0.4 |
RX86 | – | 2 ½ | – | – | 103.58 | 28.58 | 15.09 | 0.81 |
RX87 | – | 3 | – | – | 113.11 | 28.58 | 15.09 | 0.9 |
RX88 | – | 4 | – | – | 139.29 | 31.75 | 17.48 | 1.46 |
RX89 | – | 3 ½ | – | – | 129.77 | 31.75 | 18.26 | 3.09 |
RX90 | – | 5 | – | – | 174.63 | 44.45 | 19.84 | 7.75 |
RX91 | – | 10 | – | – | 286.94 | 45.24 | 30.18 | 1.5 |
RX99 | 8 | – | 8 | – | 245.67 | 25.4 | 11.91 | 2.2 |
RX201 | – | – | – | 1 3/8 | 51.46 | 11.3 | 5.74 | 0.1 |
RX205 | – | – | – | 1 13/16 | 62.31 | 11.1 | 5.56 | 0.13 |
RX210 | – | – | – | 2 9/16 | 97.64 | 19.05 | 9.53 | 0.35 |
RX215 | – | – | – | 4 1/16 | 140.89 | 25.4 | 11.91 | 0.8 |
Style BX Ring Joint Gaskets Dimensions
RTJ GASKET RING NUMBER | 2000# | 3000# | 5000# | 10000# | 15000# | 20000# | OUTSIDE DIA | HEIGHT OF THE RING |
WIDTH OF THE RING |
RTJ GASKET WEIGHT KG |
BX 150 | – | – | – | 1 11/16 | 1 11/16 | – | 72.19 | 9.3 | 9.3 | 0.13 |
BX 151 | – | – | – | 1 13/16 | 1 13/16 | 1 13/16 | 76.4 | 9.63 | 9.63 | 0.15 |
BX 152 | – | – | – | 2 1/16 | 2 1/16 | 2 1/16 | 84.68 | 10.24 | 10.24 | 0.19 |
BX 153 | – | – | – | 2 9/16 | 2 9/16 | 2 9/16 | 100.94 | 11.38 | 11.38 | 0.29 |
BX 154 | – | – | – | 3 1/16 | 3 1/16 | 3 1/16 | 116.84 | 12.4 | 12.4 | 0.4 |
BX 155 | – | – | – | 4 1/16 | 4 1/16 | 4 1/16 | 147.96 | 14.22 | 14.22 | 0.55 |
BX 156 | – | – | – | 7 1/16 | 7 1/16 | 7 1/16 | 237.92 | 18.62 | 18.62 | 1.87 |
BX 157 | – | – | – | 9 | 9 | 9 | 294.46 | 20.98 | 20.98 | 2.97 |
BX 158 | – | – | – | 11 | 11 | 11 | 352.04 | 23.14 | 23.14 | 4.35 |
BX 159 | – | – | – | 13 5/8 | – | – | 426.72 | 25.7 | 25.7 | 6.53 |
BX 160 | – | – | 13 5/8 | – | – | – | 402.59 | 23.83 | 13.74 | 3.06 |
BX 161 | – | – | 16 ¾ | – | – | – | 491.41 | 28.07 | 16.21 | 5.35 |
BX 162 | – | – | 16 3/4 | 16 3/4 | 16 3/4 | – | 475.49 | 14.22 | 14.22 | 1.94 |
BX 163 | – | – | 18 3/4 | – | – | – | 556.16 | 30.1 | 17.37 | 6.9 |
BX 164 | – | – | – | 18 3/4 | 18 3/4 | – | 570.56 | 30.1 | 24.59 | 5.86 |
BX 165 | – | – | 21 ¼ | – | – | – | 624.71 | 32.03 | 18.49 | 8.76 |
BX 166 | – | – | – | 21 ¼ | – | – | 640.03 | 32.03 | 26.14 | 12.82 |
BX 167 | 26 3/4 | – | – | – | – | – | 759.36 | 35.86 | 13.11 | 8.53 |
BX 168 | – | 26 3/4 | – | – | – | – | 765.25 | 35.86 | 16.05 | 10.54 |
BX 169 | – | – | – | 5 1/8 | – | – | 173.51 | 15.85 | 12.93 | 0.73 |
BX 170 | – | – | – | 6 5/8 | 6 5/8 | – | 218.03 | 14.22 | 14.22 | 1.03 |
BX 171 | – | – | – | 8 9/16 | 8 9/16 | – | 267.44 | 14.22 | 14.22 | 1.24 |
BX 172 | – | – | – | 11 5/32 | 11 5/32 | – | 333.07 | 14.22 | 14.22 | 1.56 |
BX 303 | 30 | 30 | – | – | – | – | 852.75 | 37.95 | 16.97 | – |
HOW TO ORDER RING JOINT GASKET
The following tables shows how to select the correct ring joint gasket depending on the flange size (NPS), manufacturing norm (ASME or API) and flange rating:
Style R Ring Joint Gaskets
NOMINAL PIPE SIZE | PRESSURE CLASSES | ||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
ASME B16.5 | API 6B | ASME B16.47 Series A | |||||||||||||
150# | 300# – 600# | 900# | 1500# | 2500# | 720# – 960# (1) | 2000# | 3000# | 5000# | 10000# | 150# | 300# – 600# | 900# | |||
1/2” | – | R-11 | R-12 | R-12 | R-13 | – | – | – | – | – | – | – | – | ||
3/4” | – | R-13 | R-14 | R-14 | R-16 | – | – | – | – | – | – | – | – | ||
1” | R-15 | R-16 | R-16 | R-16 | R-18 | R-16 | R-16 | R-16 | R-16 | R-82 | – | – | – | ||
1 1/4” | R-17 | R-18 | R-18 | R-18 | R-21 | R-18 | R-18 | R-18 | R-18 | – | – | – | – | ||
1 1/2” | R-19 | R-20 | R-20 | R-20 | R-23 | R-20 | R-20 | R-20 | R-20 | R-84 | – | – | – | ||
2” | R-22 | R-23 | R-24 | R-24 | R-26 | R-23 | R-23 | R-23 | R-24 | R-85 | – | – | – | ||
2 1/2” | R-25 | R-26 | R-27 | R-27 | R-28 | R-26 | R-26 | R-26 | R-27 | R-86 | – | – | – | ||
3” | R-29 | R-31 | R-31 | R-35 | R-32 | R-31 | R-31 | R-31 | R-35 | R-87 | – | – | – | ||
3 1/2” | R-33 | R-34 | – | – | – | – | – | – | R-37 | R-89 | – | – | – | ||
4” | R-36 | R-37 | R-37 | R-39 | R-38 | R-37 | R-37 | R-37 | R-39 | R-88 | – | – | – | ||
5” | R-40 | R-41 | R-41 | R-44 | R-42 | R-41 | R-41 | R-41 | R-44 | R-90 | – | – | – | ||
6” | R-43 | R-45 | R-45 | R-46 | R-47 | R-45 | R-45 | R-45 | R-46 | – | – | – | – | ||
8” | R-48 | R-49 | R-49 | R-50 | R-51 | R-49 | R-49 | R-49 | R-50 | – | – | – | – | ||
10” | R-52 | R-53 | R-53 | R-54 | R-55 | R-53 | R-53 | R-53 | R-54 | R-91 | – | – | – | ||
12” | R-56 | R-57 | R-57 | R-58 | R-60 | R-57 | R-57 | R-57 | – | – | – | R-57 | R-57 | ||
14” | R-59 | R-61 | R-62 | R-63 | – | R-61 | R-61 | R-61 | – | – | – | R-61 | R-62 | ||
16” | R-64 | R-65 | R-66 | R-67 | – | R-65 | R-65 | R-65 | – | – | – | R-65 | R-66 | ||
18” | R-68 | R-69 | R-70 | R-71 | – | R-69 | R-69 | R-69 | – | – | – | R-69 | R-70 | ||
20” | R-72 | R-73 | R-74 | R-75 | – | R-73 | R-73 | R-73 | – | – | – | R-73 | R-74 | ||
22” | – | – | – | – | – | – | – | – | – | – | R-80 | R-81 | – | ||
24” | R-76 | R-77 | R-78 | R-79 | – | – | – | – | – | – | – | R-77 | R-78 | ||
26” | – | – | – | – | – | – | – | – | – | – | – | R-93 | R-100 | ||
28” | – | – | – | – | – | – | – | – | – | – | – | R-94 | R-101 | ||
30” | – | – | – | – | – | – | – | – | – | – | – | R-95 | R-102 | ||
32” | – | – | – | – | – | – | – | – | – | – | – | R-96 | R-103 | ||
34” | – | – | – | – | – | – | – | – | – | – | – | R-97 | R-104 | ||
36” | – | – | – | – | – | – | – | – | – | – | – | R-98 | R-105 |
Style RX Ring Joint Gaskets
NPS | PRESSURE RATING | |||||
---|---|---|---|---|---|---|
API 6B | ||||||
720# | 960# | 2000# | 2900# | 3000# | 5000# | |
1” | – | – | – | RX-82 | – | – |
1 3/8” | – | – | – | – | – | RX-201 |
1 1/2” | RX-20 | RX-20 | RX-20 | RX-84 | RX-20 | RX-20 |
1 13/16″ | – | – | – | – | – | RX205 |
2” | RX-23 | RX-23 | RX-23 | RX-85 | RX-24 | RX-24 |
2 1/2” | RX-26 | RX-26 | RX-26 | RX-86 | RX-27 | RX-27 |
2 9/16” | – | – | – | – | – | RX210 |
3” | RX-31 | RX-31 | RX-31 | RX-87 | RX-31 | RX35 |
3 1/2” | – | – | – | RX-89 | – | – |
4” | RX-37 | RX-37 | RX-37 | RX-88 | RX-37 | RX-39 |
4 1/16″ | – | – | – | – | – | RX-215 |
5” | RX-41 | RX-41 | RX-41 | RX-90 | RX-41 | RX-44 |
6” | RX-45 | RX-45 | RX-45 | – | RX-45 | RX-46 |
8” | RX-49 RX-99 (2) |
RX-49 | RX-49 | – | RX-49 RX-99 (2) |
RX-50 |
10” | RX-53 | RX-53 | RX-53 | RX-91 | RX-53 | RX-54 |
12” | RX-57 | RX-57 | RX-57 | – | RX-57 | – |
14” | – | – | – | – | – | RX-63 |
16” | RX-65 | RX-65 | RX-65 | – | RX-69 | – |
18” | RX-69 | RX-69 | RX-69 | – | RX-73 | – |
20” | RX-73 | RX-73 | RX-73 | – | RX82 | – |
Style BX Ring Joint Gaskets
NPS | PRESSURE RATING | |||||
---|---|---|---|---|---|---|
API 6BX | ||||||
2000# | 3000# | 5000# | 10000# | 15000# | 20000# | |
1 11/16″ | – | – | – | BX-150 | BX-150 | – |
1 13/16″ | – | – | – | BX-151 | BX-151 | BX-151 |
2 1/16″ | – | – | – | BX-152 | BX-152 | BX-152 |
2 9/16″ | – | – | – | BX-153 | BX-153 | BX-153 |
3 1/16″ | – | – | – | BX-154 | BX-154 | BX-154 |
4 1/16″ | – | – | – | BX-155 | BX-155 | BX-155 |
5 1/8″ | – | – | – | BX-169 | – | – |
6 5/8″ | – | – | – | BX-170 | BX-170 | – |
7 1/16″ | – | – | – | BX-156 | BX-156 | BX-156 |
8 9/16″ | – | – | – | BX-171 | BX-171 | – |
9″ | – | – | – | BX-157 | BX-157 | BX-157 |
11″ | – | – | – | BX-158 | BX-158 | BX-158 |
11 5/32″ | – | – | – | BX-172 | BX-172 | – |
13 5/8″ | – | – | BX-160 | BX-159 | BX-159 | BX-159 |
16 3/4″ | – | – | BX-161 BX-162 | BX-162 | BX-162 | – |
18 3/4″ | – | – | BX-163 | BX-164 | BX-164 | – |
21 1/4″ | – | – | BX-165 | BX-166 | – | – |
26 3/4″ | BX-167 | BX-168 | – | – | – | – |
30″ | BX-303 | BX-303 | – | – | – | – |
KAMMPROFILE GASKET
KAMMPROFILE GASKET DEFINITION
A Kammprofile gasket is manufactured by applying a sealing layer in non-metallic materials (such as graphite, PTFE-Teflon, ceramic fibers, non-asbestos, Mica, etc) or metallic materials (as aluminum or silver) on both sides of a metal core featuring concentric grooves of 1 mm Cam-Pitch. This sealing product, called also “grooved metal gasket” or “corrugated metal gasket”, is used for high-pressure and temperature oil & gas applications.
Kammprofile gaskets are used in many industrial, petrochemical, power generation and nuclear installations (to seal flanges, heat exchangers, superheaters and, other pressure equipment) and are preferred to Spiral Wound Gaskets for processes with constant high pressure/temperatures requiring strong bolt-loads and remarkable flanged joints’ resistance.
A Kammprofile gasket offers several benefits, due to its wide sealing area and construction:
- May resist temperatures up to approx. 1000°C (the Kammprofile temperature rating depends on the materials of the metal core and the sealing layer)
- May rate up to 250 bars, which is a considerable pressure rating
- The gasket does not damage the flange surface, due to the protection offered by the sealing layer
- The gasket can absorb fluctuations in temperature and pressure
- It is more tolerant than Spiral Wound Gaskets to improper bolting torques
- Suits both light and heavyweight flanges, even of large sizes
- After assembly, the thickness of the sealing material is extremely low (0.1 – 0.2 mm), thus reducing leaks and failure rates
- The core of a Kammprofile gasket can be re-used after cleaning and fitting the gasket with a new layering material. This is critical for expensive applications, such as heat exchanger gaskets that are made of exotic, expensive, materials (Inconel, Monel, Hastelloy, and Cupronickel).
An outer metallic (integral or floating) ring may be added to the gasket, to facilitate the centering of the gasket during the installation on a flange. The sealing layers protect the flange surface and reinforce the seal.
KAMMPROFILE GASKET TYPES
Kammprofile gaskets are available in two main configurations, parallel root cores/convex root cores, and two designs (with/without loose outer centering ring), as shown in the image below:
KAMMPROFILE GASKET MATERIALS
Metal Core Materials
The core material of a Kammprofile gasket shall match the material of the piping system
Kammprofile Core Materials | DIN Designation |
DIN Material Number | AISI ASTM UNS Designation |
British Standard Designation |
Hardness HB/HV |
Temperature in C° Min. Max. |
Density in gr/cm3 | |
Soft Iron | – | – | – | – | 90 – 100 | – 60 | 500 | 7.85 |
Steel (LCS) | RSt. 37.2 | 1.0038 | – | – | 100 – 130 | – 40 | 500 | 7.85 |
Stainless Steel 304 | X5 CrNi 1810 | 1.4301 | 304 | 304S15/16/31 | 130 – 180 | -250 | 550 | 7.9 |
Stainless Steel 304 L | X2CrNi 1911 | 1.4306 | 304L | 304S11 | 130 – 190 | -250 | 550 | 7.9 |
Stainless Steel 309 | X15CrNiSi 2012 | 1.4828 | 309 | 309S24 | 130 – 190 | -100 | 1000 | 7.9 |
Stainless Steel 316 L(1) | X2CrNiMo 1713 | 1.4404 | 316L | 316S11/13 | 130 – 190 | -100 | 550 | 7.9 |
Stainless Steel 316 Ti | X6CrNiMoTi 1712 | 1.4571 | 316Ti | 320S31 | 130 – 190 | -100 | 550 | 7.8 |
Stainless Steel 321 | X6CrNiTi 1810 | 1.4541 | 321 | 321S12/49/87 | 130 – 190 | -250 | 550 | 7.9 |
Stainless Steel 347 | X6CrNiNb 1810 | 1.4550 | 347 | 347S31 | 130 – 190 | -250 | 550 | 7.9 |
Aluminium | Al 99,5 | 3.0255 | – | – | 20 – 23 | -250 | 300 | 2.73 |
Silver | – | – | – | – | 28* | -250 | 750 | 10.5 |
Copper | – | 2.0090 | – | – | 50 – 80 | -250 | 400 | 8.9 |
Nickel 200 | Ni 99,2 | 2.4066 | N02200 | 3072-76 NA11 | 90 – 120 | -250 | 600 | 8.9 |
Monel 400 ® | NiCu 30 Fe | 2.4360 | N04400 | 3072-76 NA13 | 110 – 150 | -125 | 600 | 8.8 |
Inconel 600 ® | NiCr 15 Fe | 2.4816 | N06600 | 3072-76 NA14 | 120 – 180 | -100 | 950 | 8.4 |
Incoloy 800 ® | X10NiCrAITi 3220 | 1.4876 | N08800 | 3072-76 NA15 | 140 – 220 | -100 | 850 | 8.0 |
Incoloy 825 ® | NiCr 21 Mo | 2.4858 | N08825 | 3072-76 NA16 | 120 – 180 | -100 | 450 | 8.14 |
Hastelloy B2 ® | NiMo 28 | 2.4617 | N10665 | – | 170 – 230 | -200 | 450 | 9.2 |
Hastelloy C276 ® | NiMo16Cr15W | 2.4819 | N10276 | – | 170 – 230 | -200 | 450 | 8.9 |
Titanium | Ti 99,8 | 3.7025 | – | – | 110 – 140 | -250 | 350 | 4.5 |
Sealing Layer
The most common layer materials for Kammprofile gaskets are graphite and PTFE (Teflon).
The advantages of a graphite layering material are:
- Excellent gas tightness qualities
- Non-aging properties
- Very good chemical resistance
- Resistance to high (fluctuating) temperatures and pressures
PTFE is also used due to its excellent chemical resistance, resistance to temperatures up to 250°C and excellent sealing properties for gas applications.
Sealing Layer Material for Kammprofile | Temperature in C° Min. Max. |
Max. operating pressure in Bars | Gas tightness | Recommended Application | |
Graphite | -200 | 550 | 250 | Good | Aggressive media |
PTFE (Teflon ® ) | -200 | 250 | 100 | Good | Aggressive media |
Non-asbestos | -100 | 250 | 100 | Good | Gas and liquids |
Silver | -200 | 750 | 250 | Good | Aggressive media |
KAMMPROFILE GASKET DIMENSIONS
Class 150-400
Kammprofile gasket dimensions for AMSE B16.5 flanges
NPS | d1 | d2 | d3 | ||
150 | 300 | 400 | |||
1/2 | 23 | 33.3 | 44.4 | 50.8 | 50.8 |
3/4 | 28.6 | 39.7 | 53.9 | 63.5 | 63.5 |
1 | 36.5 | 47.6 | 63.5 | 69.8 | 69.8 |
1¼ | 44.4 | 60.3 | 73 | 79.4 | 79.4 |
1½ | 52.4 | 69.8 | 82.5 | 92.1 | 92.1 |
2 | 69.8 | 88.9 | 101.6 | 108 | 108 |
2½ | 82.5 | 101.6 | 120.6 | 127 | 127 |
3 | 98.4 | 123.8 | 133.4 | 146.1 | 146.1 |
3½ | 111.1 | 136.5 | 158.8 | 161.9 | 158.7 |
4 | 123.8 | 154 | 171.5 | 177.8 | 174.6 |
5 | 150.8 | 182.6 | 193.7 | 212.7 | 209.5 |
6 | 177.8 | 212.7 | 219.1 | 247.7 | 244.5 |
8 | 228.6 | 266.7 | 276.2 | 304.8 | 301.6 |
10 | 282.6 | 320.7 | 336.5 | 358.8 | 355.6 |
12 | 339.7 | 377.8 | 406.4 | 419.1 | 415.9 |
14 | 371.5 | 409.6 | 447.7 | 482.6 | 479.4 |
16 | 422.3 | 466.7 | 511.2 | 536.6 | 533.4 |
18 | 479.4 | 530.2 | 546.1 | 593.7 | 590.5 |
20 | 530.2 | 581 | 603.2 | 650.9 | 644.5 |
24 | 631.8 | 682.6 | 714.4 | 771.5 | 765.2 |
All values in millimeters
Class 600-2500
Kammprofile gasket dimensions for AMSE B16.5 flanges
NPS | d1 | d2 | d3 | |||
600 | 900 | 1500 | 2500 | |||
1/2 | 23 | 33.3 | 50.8 | 60.3 | 60.3 | 66.7 |
3/4 | 28.6 | 39.7 | 63.5 | 66.7 | 66.7 | 73 |
1 | 36.5 | 47.6 | 69.8 | 76.2 | 76.2 | 82.5 |
1¼ | 44.4 | 60.3 | 79.4 | 85.7 | 85.7 | 101.6 |
1½ | 52.4 | 69.8 | 92.1 | 95.2 | 95.2 | 114.3 |
2 | 69.8 | 88.9 | 108 | 139.7 | 139.7 | 142.8 |
2½ | 82.5 | 101.6 | 127 | 161.9 | 161.9 | 165.1 |
3 | 98.4 | 123.8 | 146.1 | 165.1 | 171.5 | 193.7 |
3½ | 111.1 | 136.5 | 158.7 | … | … | … |
4 | 123.8 | 154 | 190.5 | 203.2 | 206.4 | 231.7 |
5 | 150.8 | 182.6 | 238.1 | 244.5 | 250.8 | 276.2 |
6 | 177.8 | 212.7 | 263.5 | 285.8 | 279.4 | 314.3 |
8 | 228.6 | 266.7 | 317.5 | 355.6 | 349.3 | 384.1 |
10 | 282.6 | 320.7 | 369.9 | 431.8 | 431.8 | 473 |
12 | 339.7 | 377.8 | 454 | 495.3 | 517.5 | 546.1 |
14 | 371.5 | 409.6 | 488.9 | 517.5 | 574.7 | … |
16 | 422.3 | 466.7 | 561.9 | 571.5 | 638.1 | … |
18 | 479.4 | 530.2 | 609.6 | 635 | 701.7 | … |
20 | 530.2 | 581 | 679.5 | 695.3 | 752.4 | … |
24 | 631.8 | 682.6 | 787.4 | 835 | 898.5 | … |
All values in millimeters
JACKETED GASKET
A Jacketed gasket features an inner soft material core and an outer metallic shell. The inner filler material provides resilience to the gasket, whereas the metal jacket protects the inner core of the gasket and withstands the pressure, the temperature, and the corrosion of the process.
The size range and thickness tolerances for this type of gaskets are covered by ASME B16.21 specification:
- OD: Less than 5,000mm
- Thickness: 2~8mm with tolerance +0.03 inch. to -0.000 inch (+0.8mm, -0.0mm)
JACKETED GASKET MATERIALS
Metal Jacket Materials
The table shows the most common metals used for jacketed gaskets and the recommended temperature range:
Jacket Materials | Hardness HB | Temp.℃ |
Carbon Steel | 90 | -60~+450 |
304 (L) | 130 | -270~+550 |
316 (L) | 130 | -270~+550 |
321 | 130 | -270~+550 |
Monel | 110 | -60~+500 |
Inconel | 90 | -60~+600 |
AL | 30 | -250~+300 |
CU | 80 | -250~+400 |
Inner Core Materials
Metal jacket gaskets have a soft inner core, which may be manufactured in materials as:
- Non-Asbestos millboard and other non-asbestos materials (aramid, glass fiber, inorganic fibers, etc)
- CAF
- Rubber
- PTFE
- Graphite
JACKETED GASKET TYPES
The two main types of metal jacketed gasket are the single and the double jacket designs. Besides these two basic types, other designs are available on the market as illustrated below:
|
|
JACKETED GASKET DIMENSIONS
Class 150-400

NPS | d1 | d2 | ||
150 | 300 | 400 | ||
1/2 | 23.8 | 44.5 | 50.8 | 50.8 |
3/4 | 31.8 | 54 | 63.5 | 63.5 |
1 | 36.5 | 63.5 | 69.9 | 69.9 |
1¼ | 46 | 73 | 79.4 | 79.4 |
1½ | 52.4 | 82.6 | 92.1 | 92.1 |
2 | 73.2 | 101.6 | 108 | 108 |
2½ | 85.9 | 120.6 | 127 | 127 |
3 | 107.8 | 133.4 | 146.1 | 146.1 |
4 | 131.8 | 171.5 | 177.8 | 174.7 |
5 | 152.4 | 193.8 | 212.8 | 209.5 |
6 | 190.5 | 219.1 | 247.7 | 244.5 |
8 | 238.3 | 276.3 | 304.8 | 301.7 |
10 | 285.8 | 336.6 | 358.8 | 355.6 |
12 | 342.9 | 406.4 | 419.1 | 415.9 |
14 | 374.7 | 447.7 | 482.6 | 479.5 |
16 | 425.5 | 511.2 | 536.6 | 533.4 |
18 | 489 | 546.1 | 593.7 | 590.6 |
20 | 533.4 | 603.3 | 650.9 | 644.5 |
24 | 641.4 | 714.4 | 771.6 | 765.3 |
NPS | d1 | 150 | 300 | 400 |
Class 600-2500
Jacketed gasket dimensions for AMSE B16.5 flanges
NPS | d1 | d2 | |||
600 | 900 | 1500 | 2500 | ||
1/2 | 23.8 | 50.8 | 60.4 | 60.4 | 66.8 |
3/4 | 31.8 | 63.5 | 66.7 | 66.7 | 73.1 |
1 | 36.5 | 69.9 | 76.2 | 76.2 | 82.5 |
1¼ | 46 | 79.4 | 85.8 | 85.8 | 101.6 |
1½ | 52.4 | 92.1 | 95.3 | 95.3 | 114.3 |
2 | 73.2 | 108 | 139.7 | 139.7 | 143 |
2½ | 85.9 | 127 | 161.9 | 161.9 | 165.1 |
3 | 107.8 | 146.1 | 165.1 | 171.5 | 193.8 |
4 | 131.8 | 190.5 | 203.2 | 206.5 | 231.9 |
5 | 152.4 | 238.2 | 244.6 | 250.9 | 276.3 |
6 | 190.5 | 263.6 | 285.8 | 279.4 | 314.5 |
8 | 238.3 | 317.5 | 355.6 | 349.3 | 384.3 |
10 | 285.8 | 396.9 | 431.8 | 431.8 | 473.2 |
12 | 342.9 | 454.1 | 495.3 | 517.6 | 546.1 |
14 | 374.7 | 489 | 517.6 | 574.7 | … |
16 | 425.5 | 562 | 571.5 | 638.2 | … |
18 | 489 | 609.6 | 635 | 701.8 | … |
20 | 533.4 | 679.5 | 695.5 | 752.5 | … |
24 | 641.4 | 787.4 | 835.1 | 898.6 | … |
HOW TO ORDER A METAL JACKETED GASKET
The following information should be provided to the gasket supplier to order a jacket-gasket properly:
- Outside diameter
- Inside diameter (NPS)
- Shape per standard index
- Type Number
- Thickness
- Materials (metal or metal filler)
- Bar size
- Radii
- Distance from the centerline of the gasket to the centerline of bars
26 Responses
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