Whitworth's Standard Threads for Pipes

Dimensions of Inches			Number of Threads per Inch
Nominal Bore of Pipe	Diameter of Pipe	Diameter at Bottom of Thread
	0.382	0.336	28
	0.518	0.451	19
	0.656	0.589	19
	0.826	0.734	14
	0.902	0.811	14
	1.04	0.949	14
	1.189	1.097	14
1	1.309	1.192	11
	1.492	1.375	11
	1.65	1.533	11
	1.745	1.628	11
	1.882	1.765	11
	2.022	1.965	11
	2.16	2.042	11
	2.245	2.128	11
2	2.347	2.23	11
	2.467	2.351	11
	2.587	2.47	11
	2.794	2.678	11
	3	2.882	11
	3.124	3.009	11
	3.247	3.13	11
	3.367	3.251	11
3	3.485	3.368	11
	3.698	3.581	11
	3.912	3.795	11
	4.125	4.008	11
4	4.340	4.223	11

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