Spiral Wound Gasket Dimensions Rating 150#

Dimensions of Spiral Wound Gaskets of Rating 150# as per ASME B16.20 used with Raised Face flanges ASME B16.5


150# | 300# | 400# | 600# | 900# | 1500# | 2500#

Class 150 NPS 1/2″ – 24″
NPSInner Ring Sealing ElementOuter Ring
Inside (d1) Inside (d2)Outside (d3)Outside (d4)
Dia.Dia.mmDia.mmDia.mm
1/214.219.131.847.8
3/420.625.439.657.2
126.931.847.866.8
1-1/438.147.860.576.2
1-1/244.554.169.985.9
255.669.985.9104.9
2-1/266.582.698.6124.0
381.0101.6120.7136.7
4106.4127.0149.4174.8
5131.8155.7177.8196.9
6157.2182.6209.6222.3
8215.9233.4263.7279.4
10268.2287.3317.5339.9
12317.5339.9374.7409.7
14349.3371.6406.4450.9
16400.1422.4463.6514.4
18449.3474.7527.1549.4
20500.1525.5577.9606.6
24603.3628.7685.8717.6

General notes:

  1. Dimensions are in millimeters unless otherwise indicated.
  2. Image shows a Spiral Wound gasket with Inner – and Outer ring.
  3. d1 = Inside diameter when Inner ring is used.
  4. d2 = Inside diameter sealing element when no Inner ring is used.
  5. d3 = Outside diameter of sealing element.
  6. d4 = Outside diameter of Outer ring.
  7. Thickness of inner and outer ring: 2.97 mm – 3.33 mm.
  8. Thickness sealing element: 4.45 mm.
  9. Tolerance Outside diameter for NPS 1/2 through NPS 8 is ± 0.8 mm; for NPS 10 trough NPS 24 tolerance is + 1.5 mm – 0.8 mm.
  10. ASME B16.20 does not covers class 400 flanges up to NPS 3 and class 900 flanges up to NPS 2½.
  11. There are 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.
  12. The inner ring inside diameters shown for NPS 1¼ thru 2½ in class 1500 and 2500 will produce inner ring widths of 0.12 inches, a practical minimum for production purposes.
  13. ASME B16.20 which covers spiral wound gaskets requires the use of solid metal inner rings in: Pressure Class 900, nominal pipe sizes 24 and larger, Pressure Class 1500 from nominal pipe sizes 12 and larger, Pressure Class 2500 from nominal pipe sizes 4 and larger and all PTFE filled gaskets.