Spiral Wound ANSI Class 150 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	1.88
3/4	0.81	1.00	1.56	2.25
1	1.06	1.25	1.88	2.63
1 1/4	1.50	1.88	2.38	3.00
1 1/2	1.75	2.13	2.75	3.38
2	2.19	2.75	3.38	4.13
2 1/2	2.62	3.25	3.88	4.88
3	3.19	4.00	4.75	5.38
3 1/2	—	4.50	5.25	6.38
4	4.19	5.00	5.88	6.88
5	5.19	6.13	7.00	7.75
6	6.19	7.19	8.25	8.75
8	8.50	9.19	10.38	11.00
10	10.56	11.31	12.50	13.38
12	12.50	13.38	14.75	16.13
14	13.75	14.63	16.00	17.75
16	15.75	16.63	18.25	20.25
18	17.69	18.69	20.75	21.63
20	19.69	20.69	22.75	23.88
24	23.75	24.75	27.00	28.25