AWWA C207 Class D Hub Flange

Technical Drawing

In Appendix B, AWWA C207 has also provided information on hub flanges covering Class D and Class E. Compared with ring flanges, the hub flange is furnished with an extended hub, reinforcing the flange while facilitating the welding process. The working pressure limit at water service temperature for AWWA C207 Class D hub flange is 175 psi for sizes 4″~12″ and 150 psi for sizes larger than 12″. The maximum pressure (test or transient) allowed can be up to 260 psi for Class D hub flanges in sizes 4″ through 12″ and 225 psi for Class D hub flanges larger than 12″. These flanges have the outside diameter and drilling pattern as Class 125 cast-iron flanges (ASME B16.1). In sizes 24″ and smaller, they also match ASME B16.5 Class 150 standard for steel flanges.

Dimensions & Masses

NPS	A	B	Mass
4"	9.00	4.57	3.09
5"	10.00	5.66	4.05
6"	11.00	6.72	4.79
8“	13.50	8.72	6.92
10”	16.00	10.88	10.19
12“	19.00	12.88	15.04
14”	21.00	14.19	19.37
16“	23.50	16.19	23.58
18”	25.00	18.19	23.63
20“	27.50	20.19	27.91
22”	29.50	22.19	41.60
24“	32.00	24.19	47.89
26”	34.25	26.19	54.21
28“	36.50	28.19	59.24
30”	38.75	30.19	65.25
32“	41.75	32.19	82.76
34”	43.75	34.19	86.55
36“	46.00	36.19	94.15
38”	48.75	38.19	107.51
40“	50.75	40.19	113.11
42”	53.00	42.19	130.32
44“	55.25	44.19	151.44
46”	57.25	46.19	158.17
48“	59.50	48.19	184.74
50”	61.75	50.19	191.23
52“	64.00	52.19	203.37
54”	66.25	54.19	215.81
60“	73.00	60.19	274.58
66”	80.00	66.19	326.23
72“	86.50	72.19	364.41
78”	93.00	78.19	458.78
84“	99.75	84.19	526.71
90”	106.50	90.19	649.29
96“	113.25	96.19	734.75

*A – outside diameter of flange, inch; B – inside diameter of flange, inch; Mass – weight of flange, kg.

NPS	n	C	d
4"	8	7.50	0.625
5"	8	8.50	0.750
6"	8	9.50	0.750
8“	8	11.75	0.750
10”	12	14.25	0.875
12“	12	17.00	0.875
14”	12	18.75	1.000
16“	16	21.25	1.000
18”	16	22.75	1.125
20“	20	25.00	1.125
22”	20	27.25	1.250
24“	20	29.50	1.250
26”	24	31.75	1.250
28“	28	34.00	1.250
30”	28	36.00	1.250
32“	28	38.50	1.500
34”	32	40.50	1.500
36“	32	42.75	1.500
38”	32	45.25	1.500
40“	36	47.25	1.500
42”	36	49.50	1.500
44“	40	51.75	1.500
46”	40	53.75	1.500
48“	44	56.00	1.500
50”	44	58.25	1.750
52“	44	60.50	1.750
54”	44	62.75	1.750
60“	52	69.25	1.750
66”	52	76.00	1.750
72“	60	82.50	1.750
78”	64	89.00	2.000
84“	64	95.50	2.000
90”	68	102.00	2.250
96“	68	108.50	2.250

*Drilling dimensions: n – number of bolts; C – diameter of bolt circle; d – diameter of bolts.
*For sizes ≤ 84″, Bolt holes shall be drilled 1/8″ [3.2 mm] larger in diameter than the nominal diameter of bolt; For sizes > 84″, bolt holes shall be drilled 3/16″ [4.8 mm] larger in diameter than the nominal diameter of bolt.

NPS	T	L	E
4"	0.500	0.875	5.312
5"	0.562	1.250	6.312
6"	0.562	1.250	7.562
8“	0.562	1.250	9.688
10”	0.688	1.250	12.000
12“	0.688	1.250	14.375
14”	0.750	1.250	15.750
16“	0.750	1.250	18.000
18”	0.750	1.250	19.875
20“	0.750	1.250	22.000
22”	1.000	1.750	24.250
24“	1.000	1.750	26.125
26”	1.000	1.750	28.500
28“	1.000	1.750	30.500
30”	1.000	1.750	32.500
32“	1.125	1.750	34.750
34”	1.125	1.750	36.750
36“	1.125	1.750	38.750
38”	1.125	1.750	40.750
40“	1.125	1.750	43.000
42”	1.250	1.750	45.000
44“	1.250	2.250	47.000
46”	1.250	2.250	49.000
48“	1.375	2.500	51.000
50”	1.375	2.500	53.000
52“	1.375	2.500	55.000
54”	1.375	2.500	57.000
60“	1.500	2.750	63.000
66”	1.500	2.750	69.000
72“	1.500	2.750	75.000
78”	1.750	3.000	81.250
84“	1.750	3.000	87.500
90”	2.000	3.250	93.750
96“	2.000	3.250	100.000

*T: thickness of flange, inch; L: through hub length, inch; E: diameter of hub.

AWWA C207 Pipe Flange Dimensions & Masses
Ring Flange	Class B | Class D Class E | Class F
Blind Flange	Class B | Class D Class E | Class F
Hub Flange	Class D | Class E

*Click to view more information about AWWA C207 steel flanges.