Spiral Wound ANSI Class 2500 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 and NPS 4" and larger in Class 2500.
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".
(*) There are no Class 900 flanges in NPS 1/2" through NPS 2 1/2" (use Class 1500), or Class 2500 flanges NPS 14" and larger.
ASME B16.20 does not include gaskets with no internal ring dimensions for NPS 1/4", 3 1/2" or 41/2".

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	2.75
3/4	0.81	1.00	1.56	3.00
1	1.06	1.25	1.88	3.38
1 1/4	1.31	1.56	2.38	4.13
1 1/2	1.63	1.88	2.75	4.63
2	2.06	2.31	3.38	5.75
2 1/2	2.50	2.75	3.88	6.63
3	3.10	3.63	4.75	7.75
4	3.85 (*)	4.63	5.88	9.25
5	4.90 (*)	5.63	7.00	11.00
6	5.80 (*)	6.75	8.25	12.50
8	7.75 (*)	8.50	10.13	15.25
10	9.69 (*)	10.63	12.25	18.75
12	11.50 (*)	12.50	14.50	21.63