[ Gaskets ]
Spiral Wound, Kammprofile and Compressed Fiber Gaskets
Patriot Bolt supplies gaskets for flanged joints together with the stud bolts and nuts that clamp them: spiral wound and Kammprofile gaskets to ASME B16.20, and compressed fiber ring and full face gaskets to ASME B16.21.
Tell us the flange standard, size, class and materials and we will quote the gaskets and bolting for the same joint, so the whole flange kit arrives together.
[ Quick Specs ]
Gaskets at a Glance
- Types
- Spiral wound, Kammprofile (grooved metal) and compressed fiber ring and full face gaskets
- Standards
- ASME B16.20 and B16.21 for ASME B16.5 and B16.47 Series A and B flanges, plus EN 1514, EN 12560-6, JIS B 2220, BS 3381, BS 10, NF M 87-621 and AWWA C207 sizes
- Sizes
- NPS 1/2 through 60 in ASME classes, and DN sizes for PN-rated flanges, per the charts below
- Materials
- Winding, core, ring, filler and facing materials as your specification calls for
- Supplied with
- Matching stud bolts and heavy hex nuts for each flange
Comparing Gasket Types
The right gasket depends on the flange facing, pressure class, temperature, media and available bolt load. This table summarizes how the three types differ. Your piping specification sets the final choice.
| Spiral wound | Kammprofile | Compressed fiber | |
|---|---|---|---|
| Construction | V-shaped metal strip wound with a soft filler, with a solid guide ring and, where required, an inner ring | Solid metal core with concentric serrations on both faces, covered with a soft facing, with an integral or loose guide ring | Flat sheet gasket cut as a ring or full face |
| Dimensional standard | ASME B16.20, EN 1514-2, JIS B 2220, BS 3381 and others | ASME B16.20, EN 12560-6, EN 1514-6 | ASME B16.21 |
| Flange facings | Raised face, tongue and groove, male and female | Raised face | Raised face (ring) and flat face (full face) |
| Seating stress | Higher; ASME VIII-1 suggests y = 10,000 psi | Seals at low bolt loads | Varies by sheet material; confirm with the sheet manufacturer |
| Specify | Winding metal, filler, inner and guide ring metals | Core metal, facing, guide ring | Material and thickness (1/16 or 1/8 in. common) |
Seating stress values are the suggested design values in ASME BPVC Section VIII, Division 1, Appendix 2. See our ASME gasket factor tables and gasket stress by flange size chart.
Spiral Wound Gaskets
Spiral wound gaskets are the most common gasket for raised face flanges in refinery, petrochemical and power piping. A V-shaped metal strip is wound with a soft filler such as flexible graphite or PTFE. A solid outer guide ring centers the gasket inside the bolt circle, and an inner ring fills the gap to the bore and protects the winding.
Dimension charts
| Chart | Flanges | Range |
|---|---|---|
| ASME B16.20 | ASME B16.5 raised face | NPS 1/2–24, Class 150–2500 |
| ASME B16.20 (slip-on) | ASME B16.5 slip-on, inner ring clears pipe OD | By class |
| ASME B16.47 Series A / MSS SP-44 | Large diameter | NPS 22–60, Class 150–900 |
| ASME B16.47 Series B / API 605 | Large diameter | NPS 26–60, Class 150–900 |
| Tongue and groove | Large and small tongue-and-groove joints | NPS 1/2–24 |
| Male and female | Large male-and-female joints | NPS 1/4–24 |
| RF to RTJ adapter (non-standard) | Raised face to ring-joint flange | NPS 1/2–24 |
| EN 1514-2 | PN-rated flanges | DN 10–1000 |
| JIS B 2220 | JIS flanges | 10K–63K |
| NF M 87-621 | French standard | NPS 1/2–24, Class 150, 300, 600 |
| BS 3381 | BS 1560 flanges | NPS 1/2–24, Class 150–2500 |
| BS 10 | BS 10 slip-on and weld neck, Tables D–T | NPS 1/2–24 |
| AWWA C207 Class E | Water-works slip-on and weld neck | NPS 22–66 |
Color coding
The guide ring is color coded for the winding metal, with a stripe for the filler.
| Winding metal | Guide ring color | Winding metal | Guide ring color |
|---|---|---|---|
| 304 SS | Yellow | Incoloy 800/825 | White |
| 316L SS | Green | Titanium | Purple |
| 317L SS | Maroon | Alloy 20 | Black |
| 347 SS | Blue | Carbon steel | Silver |
| 321 SS | Turquoise | Hastelloy B | Brown |
| Monel | Orange | Hastelloy C | Beige |
| Inconel 600/625 | Gold | Phosphor bronze | Copper |
| Nickel | Red |
| Filler | Stripe |
|---|---|
| PTFE | White |
| Ceramic | Light green |
| Flexible graphite | Gray |
| Phyllosilicate (HTG) | Light blue |
Marking requirements are on our gasket markings sheet. To get a scaled drawing of a spiral wound gasket with B16.20 dimensions, color code and marking, use our Gasket Drawing Generator.
Kammprofile Gaskets
Kammprofile gaskets, also called grooved metal gaskets, have a solid metal core with fine concentric serrations on both faces, covered with a thin soft facing layer of flexible graphite, PTFE or mica. An integral or loose outer guide ring centers the gasket on the bolts. They seal at low bolt loads and handle thermal cycling well.
Dimension charts
| Chart | Flanges | Range |
|---|---|---|
| ASME B16.20 | ASME B16.5 raised face | NPS 1/2–24, Class 150–2500 |
| ASME B16.47 Series A | Large diameter | NPS 26–60, Class 150–900 |
| ASME B16.47 Series B | Large diameter | NPS 26–60, Class 150–900 |
| EN 12560-6 | Class-rated flanges | NPS 1/2–24 |
| EN 1514-6 Type A and B | PN-rated flanges | DN 10–3000 |
For Kammprofile ring joint gaskets, see our Specialty RTJ Gaskets page.
To get a scaled drawing of a Kammprofile gasket with ASME B16.20 or EN 12560-6 dimensions, a detailed cross-section, color code and marking, use our Kammprofile Gasket Drawing Generator.
Compressed Fiber Gaskets
Compressed fiber gaskets are flat sheet gaskets dimensioned in ASME B16.21. A ring gasket fits inside the bolt circle of a raised face flange and is centered by the bolts. A full face gasket covers the whole face of a flat face flange, with bolt holes on the bolt circle.
Material and thickness are specified per order, with 1/16 in. and 1/8 in. the common thicknesses. The same ASME B16.21 sizes are also available in PTFE, flexible graphite or rubber when your service calls for it.
Dimension charts
| Chart | Style | Range |
|---|---|---|
| ASME B16.21 for B16.5 | Ring (raised face) | NPS 1/2–24, Class 150–600 |
| ASME B16.21 for B16.47 Series A | Ring (raised face) | NPS 26–60, Class 150–600 |
| ASME B16.21 for B16.47 Series B | Ring (raised face) | NPS 26–60, Class 150–600 |
| ASME B16.21 for B16.5 | Full face, with bolt holes | NPS 1/2–24 |
| ASME B16.21 for B16.47 Series A | Full face, with bolt holes | NPS 26–60 |
| ASME B16.21 for B16.47 Series B | Full face, with bolt holes | NPS 26–60 |
ASME B16.21 tolerances: OD +0, −1/16 in. through NPS 12 and +0, −1/8 in. for NPS 14 and up; ID ±1/16 in. through NPS 12 and ±1/8 in. for NPS 14 and up.
Ordering Details
To quote gaskets, tell us:
- Gasket type: spiral wound, Kammprofile, compressed fiber ring or full face.
- Flange standard, for example ASME B16.5 or B16.47 Series A or B, and the facing.
- Size and pressure class, or DN and PN.
- Materials: winding or core metal, filler or facing, and inner and guide ring metals. For sheet gaskets, the material and thickness.
- Quantity, and any stud bolts and nuts for the same flanges.
Our Bolting List Builder builds a complete stud, nut and gasket list by flange size and class, and the Gasket Stress Target Torque Calculator works from your target gasket stress back to bolt stress and torque. The Gasket Drawing Generator produces a spiral wound gasket drawing you can download or send to us with your quote request.
Gaskets FAQ
What types of gaskets does Patriot Bolt supply?
We supply spiral wound, Kammprofile and compressed fiber (sheet) gaskets for flanged joints, along with the stud bolts and nuts for the same flanges. Ring joint gaskets are covered on our Specialty RTJ Gaskets page.
Do I need an inner ring on a spiral wound gasket?
ASME B16.20 requires inner rings for PTFE-filled spiral wound gaskets and for some larger sizes in higher pressure classes. Many users specify inner rings on every gasket. Gaskets with inner rings should be used only with socket welding, lapped, welding neck and integral flanges.
How is a spiral wound gasket identified?
ASME B16.20 requires the guide ring to be marked with the manufacturer, nominal pipe size, pressure class, winding metal, filler material, inner and guide ring metals where they differ from carbon steel, and B16.20. The guide ring is also color coded for winding metal, with a stripe for the filler.
When is a Kammprofile gasket a better choice?
Kammprofile gaskets seal at low bolt loads and handle thermal cycling well, so they are often used where bolt load is limited or the joint sees temperature swings. Confirm the selection against your piping specification.
What is the difference between a ring gasket and a full face gasket?
A ring gasket fits inside the bolt circle of a raised face flange and is centered by the bolts. A full face gasket covers the whole flange face of a flat face flange and has bolt holes. Both are dimensioned in ASME B16.21.
Will B16.5 gasket sizes fit a large-diameter flange?
No. ASME B16.47 Series A and Series B flanges, NPS 26 and larger, have their own gasket dimensions. Use the B16.47 charts linked on this page and confirm the series of your flange.
Request a Quote
Send us the gasket type, flange standard, size, class, materials and quantity, and add the stud bolts and nuts for a complete flange kit. Call (281) 581-0176 or request a quote.