Spiral Wound ANSI Class 300 Gasket, B16.20 (in)

Dimensions to ASME B16.20 - Metallic Gaskets for Pipe Flanges: Ring-Joint, Spiral-Wound, and Jacketed
Inner rings are recommended for all graphite filled gaskets, required for all PTFE filled gaskets.
The gasket outside diameter tolerance for NPS 1/2" through NPS 8" is ±0.03"; for NPS 10" through NPS 24", +0.06", –0.03".
The gasket inside diameter tolerance for NPS 1/2" through NPS 8" is ±0.016"; for NPS 10" through NPS 24", ±0.03".
The centering ring outside diameter tolerance is ±0.03".
ASME B16.20 does not include gaskets with no internal ring dimensions for NPS 1/4" or 3 1/2".

Pipe Size (NPS)	Inner Ring Inside Diameter A	Sealing Element Inside Diameter B	Sealing Element Outside Diameter C	Outer Ring Outside Diameter D
1/2	0.56	0.75	1.25	2.13
3/4	0.81	1.00	1.56	2.63
1	1.06	1.25	1.88	2.88
1 1/4	1.50	1.88	2.38	3.25
1 1/2	1.75	2.13	2.75	3.75
2	2.19	2.75	3.38	4.38
2 1/2	2.62	3.25	3.88	5.13
3	3.19	4.00	4.75	5.88
3 1/2	—	4.50	5.25	6.50
4	4.19	5.00	5.88	7.13
5	5.19	6.13	7.00	8.50
6	6.19	7.19	8.25	9.88
8	8.50	9.19	10.38	12.13
10	10.56	11.31	12.50	14.25
12	2.50	13.38	14.75	16.63
14	13.75	14.63	16.00	19.13
16	15.75	16.63	18.25	21.25
18	17.69	18.69	20.75	23.50
20	19.69	20.69	22.75	25.75
24	23.75	24.75	27.00	30.50