Standard Pipe Diameters and DN Equivalents

The term “DN” (nominal diameter) refers to the nominal diameters of pipes. Pipes are usually classified by their internal diameters. The nominal diameter is a rounded standard value of the pipe’s external diameter and is typically expressed in inches or millimeters.

For example, if the nominal diameter of a pipe is “DN 50,” this indicates that the external diameter of the pipe is approximately 50 millimeters or 2 inches, based on a specific standard value.

These standards can vary from country to country and across industries. The most commonly used pipe standard is the American standards based on Nominal Pipe Sizes (NPS). In other countries, nominal diameters based on the metric measurement system may be used.

DN PIPE DIAMETERS

Therefore, the term “DN pipe diameters” is commonly used to specify the pipe diameters utilized in pipelines and industrial applications. To obtain more detailed information about pipe diameters and standards, it is important to refer to the documentation of a specific country or standard.

ANMA ÇAPI (mm)		OUTER DIAMETER(mm)	CİDAR KALINLIĞI(mm)	İÇ ÇAP (mm)
1/2″	DN 15	21,3	2,8	15,7
3/4″	DN 20	26,9	2,9	21,1
1″	DN 25	33,7	3,4	26,9
1 1/4″	DN 32	42,4	3,6	35,2
1 1/2″	DN 40	48,3	3,7	40,9
2″	DN 50	60,3	3,9	52,5
2 1/2″	DN 65	73.0	5,2	62,6
3″	DN 80	88,9	5,5	77,9
4″	DN 100	114,3	6	102,3
5″	DN 125	141.0	6,6	127,8
6″	DN 150	168,3	7,1	154,1
8″	DN 200	219,1	8,18	202,74
12″	DN 300	323	9,5	304
16″	DN 400	406	9,5	387
18″	DN 450	470	9,5	451

SCH NORMS
NOMINAL DIAMETER	OUTER DIAMETER (INCH)	OUTER DIAMETER (mm)	SCH 20	SCH 30	SCH 40	SCH 60	SCH 80	SCH 100	SCH 120	SCH 140	SCH 160	XXS

	1/8	10,30			1,73		2,41
	1/4	13,70			2,24		3,02
DN 10	3/8	17,10			2,31		3,20
DN 15	1/2	21,30			2,77		3,73				4,78	7,47
DN 20	3/4	26,70			2,87		3,91				5,56	7,82
DN 25	1	33,40			3,38		4,55				6,35	9,09
DN 32	1 1/4	42,20			3,56		4,85				6,35	9,70
DN 40	1 1/2	48,30			3,68		5,08				7,14	10,16
DN 50	2	60,30			3,91		5,54				8,74	11,07
DN 65	2 1/2	73,00			5,16		7,01				9,52	14,02
DN 80	3	88,90			5,49		7,62				11,13	15,24
DN 90	3 1/2	101,60			5,74		8,08
DN 100	4	114,30			6,02		8,56		11,13		13,49	17,12
DN 125	5	141,30			6,55		9,52		12,70		15,88	19,05
DN 150	6	168,30			7,11		10,97		14,27		18,26	21,95
DN 200	8	219,10	6,35	7,04	8,18	10,31	12,70	15,09	18,26	20,62	23,01
DN 250	10	273,00	6,35	7,80	9,27	12,70	15,09	18,26	21,44	25,40	28,58
DN 300	12	323,90	6,35	8,38	10,31	14,27	17,47	21,44	25,40	28,58	33,34
DN 350	14	355,60	7,92	9,52	11,13	15,09	19,05	23,82	27,79	31,75	35,71
DN 400	16	406,40	7,92	9,52	12,70	16,64	21,44	26,19	30,96	36,52	40,49
DN 450	18	457,20	7,92	11,13	14,27	19,05	23,82	29,36	34,92	39,69	45,24
DN 500	20	508,00	9,52	12,70	15,09	20,62	26,19	32,54	38,10	44,45	50,01
DN 550	22	558,80	9,52	12,70		22,22	28,60	34,92	41,28	47,62	53,98
DN 600	24	609,60	9,52	14,27	17,48	24,61	30,96	38,89	46,02	52,30	59,54