Dimension of flange

Dimension of Flange: The term “flange” typically refers to a projecting rim or edge on a pipe, valve, or other object that allows it to be connected to another object. Flanges are commonly used in piping systems to connect pipes, valves, and other equipment.

Flanges come in various sizes and dimensions, and their dimensions are specified according to industry standards. The dimensions of a flange include parameters such as:

1. Nominal Pipe Size (NPS):

   This refers to the approximate interior diameter of the flange and the pipe it is designed to fit. It is often expressed in inches.

2. Flange Outer Diameter (OD):

   The overall diameter of the flange.

3. Flange Inner Diameter (ID):

   The diameter of the opening or bore of the flange.

4. Flange Thickness (T):

   The thickness of the flange material.

5. Bolt Circle Diameter (BCD):

   The diameter of the circle formed by the centers of the bolt holes in the flange.

6. Number of Bolt Holes:

   The quantity of bolt holes in the flange.

7. Bolt Hole Diameter: The diameter of the bolt holes in the flange.

8. Raised Face (RF) or Flat Face (FF):

   Flanges can have a raised surface (RF) or a flat surface (FF) where the gasket sits.

9. Pressure Class or Rating:

   Flanges are often designed to withstand specific pressure levels, and the pressure class or rating is an important dimension.

10. Flange Face Finish:

    The surface finish of the flange face, which affects how the gasket seals.

The dimensions of flanges can vary based on the type of flange, its purpose, and the industry standards it adheres to. Common flange standards include ANSI/ASME (American National Standards Institute/American Society of Mechanical Engineers), DIN (Deutsches Institut für Normung – German Institute for Standardization), and EN (European Norm) standards.

It’s important to refer to specific industry standards or manufacturer documentation to determine the exact dimensions of a flange for a particular application.

Read more…

• Type of Flange
• pipe O.D. and I.D. Chart
• How to make a flange

DIMENSION OF RAISED FLANGES

N. B.	Out Dia	Thickness	Bolt Circle Dia	No. of Bolt	Dia of Holes
80	200	21	160	4	19
100	220	22	180	8	19
125	250	22.5	210	8	19
150	285	23	240	8	23
200	340	24.5	295	8	23
250	395	26	350	12	23
300	445	27.5	400	12	23
350	505	29	450	16	23
400	565	30	515	16	28
450	615	31.5	565	20	28
500	670	33	620	20	28
600	780	36	725	20	31
700	895	38.5	840	24	31
750	960	40	900	24	31
800	1015	41.5	950	24	34

DIMENSION OF FLANGES AS PER TABLE BS-10

 

Nominal Pipe Size	OD of Pipe	O.D.	P.C.D.	No.of Bolt	Dia of Bolt	Thickness
1/2″	21.3	95.3	66.7	4	12.7	4.8
3/4″	26.7	101.6	73	4	12.7	4.8
1″	33.4	114.3	82.6	4	12.7	4.8
1 1/4″	42.2	120.7	87.3	4	12.7	6.4
1 1/2″	48.3	133.4	98.4	4	12.7	6.4
2″	60.3	152.4	114.3	4	15.9	7.9
2 1/2″	73	165.1	127	4	15.9	7.9
3″	88.9	184.2	146.1	4	15.9	9.5
3 1/2″	101.6	203.2	165.1	4	15.9	9.5
4″	114.3	215.9	177.8	4	15.9	9.5
5″	141.3	254	209.6	8	15.9	12.7
6″	168.3	279.4	228.6	8	15.9	12.7
7″	190.5	304.8	260.4	8	15.9	12.7
8″	219.1	336.6	292.1	8	15.9	12.7
9″	244.5	368.3	323.9	8	15.9	15.9
10″	273	406.4	355.6	8	19.1	15.9
12″	323.9	457.2	406.4	12	19.1	15.9
14″	355.6	527.1	469.9	12	22.2	19.1
16″	406.4	577.9	520.7	12	22.2	19.1
18″	457.2	641.4	584.2	12	22.2	22.2
20″	508	704.9	641.4	16	22.5	25.4
24″	609.6	825.5	755.7	16	25.4	28.6

Working Steam Pressure upto 100 Ibs per sq. Inch

Nominal Pipe Size	O.D. of Pipe	O.D.	P.C.D.	No. of Bolt	Dia of Bolt	Thickess
1/2″	21.3	95.3	66.3	4	12.7	6.4
3/4″	26.7	101.6	73	4	12.7	6.4
1″	33.4	114.3	82.6	4	12.7	7.1
1.1/4″	42.2	120.7	87.3	4	12.7	7.9
1.1/2″	48.3	133.4	98.4	4	12.7	8.7
2″	60.3	152.4	114.3	4	15.9	9.5
2.1/2″	73	165.1	127	4	15.9	10.3
3″	88.9	184.2	146.1	4	15.9	11.1
3.1/2″	101.6	203.2	165.1	8	15.9	11.9
4″	114.3	215.9	177.8	8	15.9	12.7
5″	141.3	254	209.6	8	15.9	14.3
6″	168.3	279.4	228.6	8	19.1	17.5
7″	190.5	304.8	260.4	8	19.1	19.1
8″	219.1	336.6	292.1	8	19.1	19.1
9″	244.5	368.3	323.9	12	19.1	20.6
10″	273	406.4	355.6	12	19.1	22.2
12″	323.9	257.2	406.4	12	22.2	25.4
14″	355.6	527.2	469.9	12	22.2	25.4
16″	406.4	577.9	520.7	12	22.2	25.4
18″	457.2	641.4	584.2	16	22.2	28.6
20″	508	704.9	647.4	16	22.2	31.8
24″	609.6	825.5	755.7	16	25.4	38.1

Working Steam Pressure above 100 Ibs and upto150 Ibs per sq. Inch

Nominal Pipe Size	O.D. of Pipe	O.D.	P.C.D.	No. of Bolt	Dia of Bolt	Thickness
1/2″	21.3	95.3	66.7	4	12.7	9.5
3/4″	26.7	101.6	73	4	12.7	9.5
1″	33.4	120.7	87.3	4	15.9	9.5
1.1/4″	42.2	133.4	98.4	4	15.9	12.7
1.1/2″	48.3	1397	104.8	4	15.9	12.7
2″	60.3	165.1	127	4	15.9	15.9
2.1/2″	73	184.2	146.1	8	15.9	15.9
3″	88.9	203.2	165.1	8	15.9	15.9
3.1/2″	101.6	215.9	177.8	8	15.9	19.1
4″	114.3	228.6	190.5	8	15.9	19.1
5″	141.3	279.4	235	8	19.1	22.2
6″	168.3	304.8	260.4	12	19.1	22.2
7″	190.5	336.6	292.1	12	19.1	22.2
8″	219.1	368.3	323.9	12	19.1	25.4
9″	244.5	406.4	355.6	12	22.2	25.4
10″	273	431.8	381	12	22.2	25.4
12″	323.9	489	438.2	16	22.2	28.6
14′	355.6	552.5	495.3	16	25.4	31.8
16″	406.4	609.6	552.5	20	25.4	31.8
18″	457.2	673.8	609.6	20	28.6	34.9
20″	508	736.9	673.1	24	28.6	38.1
24″	609.6	850.9	781.1	24	31.8	41.3

Working Steam Pressure above 150 Ibs and upto 250 Ibs per sq. Inch

Nominal Pipe Size	O.D. of Pipe	O.D.	P.C.D.	No. of Bolt	Dia of Bolt	Thickness
1/2″	21.3	114.3	82.6	4	15.9	12.7
3/4″	26.7	114.3	82.6	4	15.9	12.7
1″	33.4	120.7	87.3	4	15.9	14.3
1.1/4″	42.2	133.4	98.4	4	15.9	17.5
1.1/2″	48.3	139.7	104.8	4	15.9	17.5
2″	60.3	165.1	127	4	15.9	19.1
2.1/2″	73	184.2	146.1	8	15.9	19.1
3″	88.9	203.2	165.1	8	15.9	22.2
3.1/2″	101.6	215.9	177.8	8	15.9	22.2
4″	114.3	228.6	190.5	8	15.9	25.4
5″	141.3	279.4	235	8	19.1	28.6
6″	168.3	304.8	260.4	12	19.1	28.6
7″	190.5	336.6	292.1	12	19.1	31.8
8″	219.1	368.3	323.9	12	19.1	31.8
9″	244.5	406.4	355.6	12	22.2	34.9
10″	273	431.8	381	12	22.2	34.9
12″	323.9	489	438.2	16	22.2	38.1
14′	355.6	552.5	495.3	16	25.4	41.3
16″	406.4	609.6	552.5	20	25.4	44.5
18″	457.2	673.8	609.6	20	28.6	47.6
20″	508	736.9	673.1	24	28.6	50.8
24″	609.6	850.9	781.1	24	31.8	57.2