Materials & preparation

Pipe Data: Wall Thickness and Weight per SDR and PN

Look up wall thickness and kg/m for PE and PP pipes, and calculate values yourself when the table does not cover your dimension.

SDR Determines the Wall Thickness

The wall thickness is found by dividing the outside diameter by the SDR value. An Ø63 pipe in SDR 17 thus has 63 divided by 17 = 3.7 mm as the minimum wall thickness. The correlation and significance of PN are explained in SDR, PN and Pipe Classes.

The weight per metre follows from the cross-section: a pipe with outside diameter D and wall thickness e weighs approx. pi x (D - e) x e x density. PE is around 0.95 g/cm3 and PP around 0.91 g/cm3, making PP pipes lighter than PE pipes with the same dimensions.

Material	SDR	PN
PE 40	SDR 26 / 17 / 11	PN 2,5 / 4 / 6
PE 63	SDR 41 / 33 / 26 / 11	PN 2,0 / 2,5 / 3,2 / 8,0
PE 80	SDR 41 / 33 / 26 / 17,6 / 17 / 11 / 9	PN 2,5 / 3,2 / 4,0 / 6,0 / 6,3 / 10 / 16
PE 100	SDR 41 / 33 / 26 / 22 / 17 / 13,6 / 11 / 9 / 7,4 / 6	PN 4 / 5 / 6,3 / 8 / 10 / 12,5 / 16 / 20 / 25 / 32

The correlation applies at 20 degrees Celsius and a 50-year service life. Always use the pipe supplier's specifications, as blends and temperatures shift the limits.

PE Pipes: Wall Thickness and Weight

The table shows the four SDR classes most commonly used for water and compressed air. The wall thickness is the minimum value, and the weight is the theoretical kg/m for PE.

Outside diameter	SDR 26 wall	SDR 26 kg/m	SDR 17 wall	SDR 17 kg/m	SDR 11 wall	SDR 11 kg/m	SDR 9 wall	SDR 9 kg/m
Ø63	2,5 mm	0,48	3,8 mm	0,76	5,8 mm	1,10	7,1 mm	1,32
Ø75	2,9 mm	0,69	4,5 mm	1,07	6,8 mm	1,54	8,4 mm	1,85
Ø90	3,5 mm	0,97	5,4 mm	1,53	8,2 mm	2,23	10,1 mm	2,66
Ø110	4,2 mm	1,44	6,6 mm	2,28	10,0 mm	3,30	12,3 mm	3,96
Ø125	4,8 mm	1,85	7,4 mm	2,90	11,4 mm	4,27	14,0 mm	5,12
Ø140	5,4 mm	2,33	8,3 mm	3,64	12,7 mm	5,34	15,7 mm	6,43
Ø160	6,2 mm	3,05	9,5 mm	4,75	14,6 mm	7,00	17,9 mm	8,39
Ø180	6,9 mm	3,81	10,7 mm	6,00	16,4 mm	8,83	20,1 mm	10,60
Ø200	7,7 mm	4,72	11,9 mm	7,39	18,2 mm	10,90	22,4 mm	13,12
Ø225	8,6 mm	5,92	13,8 mm	9,38	20,5 mm	13,79	25,2 mm	16,60
Ø250	9,6 mm	7,34	14,4 mm	11,48	22,7 mm	17,03	27,9 mm	20,43
Ø280	10,7 mm	9,16	16,6 mm	14,43	25,4 mm	21,32	31,3 mm	25,66
Ø315	12,1 mm	11,67	18,7 mm	18,27	28,6 mm	27,04	35,2 mm	32,47
Ø355	13,6 mm	14,92	21,1 mm	23,26	32,2 mm	34,27	39,7 mm	41,27
Ø400	15,3 mm	18,70	23,7 mm	29,40	36,3 mm	43,53	44,7 mm	52,36
Ø450	17,2 mm	23,64	26,7 mm	37,26	40,9 mm	55,17	50,3 mm	66,28
Ø500	19,1 mm	29,16	29,7 mm	46,05	45,4 mm	68,04	55,8 mm	81,72
Ø560	21,4 mm	36,55	33,2 mm	57,66	50,8 mm	85,28	62,2 mm	102,11
Ø630	24,1 mm	46,31	37,4 mm	73,07	57,2 mm	108,02	70,0 mm	129,23

Theoretical values for PE at approx. 0.95 g/cm3. SDR 26 corresponds to PN 6.3, SDR 17 to PN 10, SDR 11 to PN 16, and SDR 9 to PN 20 for PE 100. Weight varies with tolerances and material selection.

PP Pipes: Wall Thickness and Weight

PP pipes are more frequently specified by PN than by SDR. The table shows PN 10 and PN 16, which are the classes used for pressure-bearing installations and for PP pipes in food and process plants.

Outside diameter	PN 10 wall	PN 10 kg/m	PN 16 wall	PN 16 kg/m
Ø63	5,8 mm	1,01	8,6 mm	1,41
Ø75	6,8 mm	1,41	10,3 mm	2,01
Ø90	8,2 mm	2,03	12,3 mm	2,87
Ø110	10,0 mm	3,01	15,1 mm	4,30
Ø125	11,4 mm	3,91	17,1 mm	5,53
Ø140	12,7 mm	4,87	19,2 mm	6,95
Ø160	14,6 mm	6,38	21,9 mm	9,40
Ø180	16,4 mm	8,07	24,6 mm	11,40
Ø200	18,2 mm	9,95	27,4 mm	14,10
Ø225	20,5 mm	12,60	30,8 mm	17,90
Ø250	22,7 mm	15,50	34,2 mm	22,10
Ø280	25,4 mm	19,40	38,3 mm	27,60
Ø315	28,6 mm	24,60	41,2 mm	31,40
Ø355	32,2 mm	31,20	-	-
Ø400	36,3 mm	39,60	-	-

PN 16 is not standard above Ø315 in this table. The weight is theoretical for PP at approx. 0.91 g/cm3, so it is lower than for a PE pipe with the same dimensions.

Calculate the Weight Yourself

The formula is mass per metre = pi x (D - e) x e x density / 1000, when D and e are entered in mm and the density in g/cm3. For an Ø315 pipe in SDR 11, where the wall thickness is 28.6 mm, this yields pi x 286.4 x 28.6 x 0.95 / 1000 = approx. 24.5 kg/m.

To obtain the total weight of a section, multiply the kg/m by the length and add the weight of the fittings. For lifting and transport, it is the total weight that matters, not the weight per metre alone.

What Weight Means During Welding

The wall thickness determines the heating time and cooling time, and thus how long the joint must remain undisturbed. The weight determines how the pipe is supported so that the joint is not pulled out of alignment during cooling.

For large diameters, the pipe's own weight contributes to loading the joint. Use roller cradles or supports, and never lift by the welded section until the cooling time has elapsed. Cooling times can be found in welding tables.

When planning lifting, transport, and machine selection, it is also useful to know the carriage weight of the machine you are using. This is described in butt welding machine selection.

PE 80 and PE 100 in the Same System

PE 80 and PE 100 with the same diameter and wall thickness can be butt welded together. For electrofusion welding, they can be combined when the diameter is the same, regardless of wall thickness, provided that the fitting is approved for the combination.

In contrast, for butt welding, the wall thickness must match because heating and pressure are calculated based on the wall thickness. If in doubt about the material combination, you can check it in what can be welded together.