Flange Bolt Chart

Lookup flange bolt lengths, wrench sizes, and torque sequences right on your phone. In seconds.

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Flange Bolt Chart - Bolt Lengths, Wrench Sizes & Torque Patterns

150 LB. Flanges

Nominal Pipe Size
(inches)
Wrench Size
(inches)
Number of Studs Diameter of Studs
(inches)
Length of Stud - RF
(inches)
Length of Stud - RTJ
(inches)
Suggested Torque
1/2 7/8 4 0.5 2-1/4 30
3/4 7/8 4 0.5 2-1/2 30
1 7/8 4 0.5 2-1/2 3 40
1-1/4 7/8 4 0.5 2-3/4 3-1/4 40
1-1/2 7/8 4 0.5 2-3/4 3-1/4 40
2 1-1/16 4 0.63 3-1/4 3-3/4 80
2-1/2 1-1/16 4 0.63 3-1/2 4 80
3 1-1/16 4 0.63 3-1/2 4 110
3-1/2 1-1/16 8 0.63 3-1/2 4 80
4 1-1/16 8 0.63 3-1/2 4 100
5 1-1/4 8 0.75 3-3/4 4-1/4 120
6 1-1/4 8 0.75 4 4-1/2 130
8 1-1/4 8 0.75 4-1/4 4-3/4 130
10 1-7/16 12 0.88 4-1/2 5 215
12 1-7/16 12 0.88 4-3/4 5-1/4 220
14 1-5/8 12 1 5-1/4 5-3/4 320
16 1-5/8 16 1 5-1/4 5-3/4 320
18 1-13/16 16 1.13 5-3/4 6-1/4 450
20 1-13/16 20 1.13 6-1/4 6-3/4 450
24 2 20 1.25 6-3/4 7-1/4 650

300 LB. Flanges

Nominal Pipe Size
(inches)
Wrench Size
(inches)
Number of Studs Diameter of Studs
(inches)
Length of Stud - RF
(inches)
Length of Stud - RTJ
(inches)
Suggested Torque
1/2 7/8 4 0.5 2-1/2 3 40
3/4 1-1/16 4 0.63 3 3-1/2 60
1 1-1/16 4 0.63 3 3-1/2 80
1-1/4 1-1/16 4 0.63 3-1/4 3-3/4 80
1-1/2 1-1/4 4 0.75 3-1/2 4 110
2 1-1/16 8 0.63 3-1/2 4 110
2-1/2 1-1/4 8 0.75 4 4-1/2 150
3 1-1/4 8 0.75 4-1/4 4-3/4 150
3-1/2 1-1/4 8 0.75 4-1/4 5 150
4 1-1/4 8 0.75 4-1/2 5 180
5 1-1/4 8 0.75 4-3/4 5-1/4 180
6 1-1/4 12 0.75 4-3/4 5-1/2 170
8 1-7/16 12 0.88 5-1/2 6 265
10 1-5/8 16 1 6-1/4 6-3/4 320
12 1-13/16 16 1.13 6-3/4 7-1/4 450
14 1-13/16 20 1.13 7 7-1/2 450
16 2 20 1.25 7-1/2 8 650
18 2 24 1.25 7-3/4 8-1/4 650
20 2 24 1.25 8 8-3/4 650
24 2-3/8 24 1.5 9 10 1200

600 LB. Flanges

Nominal Pipe Size
(inches)
Wrench Size
(inches)
Number of Studs Diameter of Studs
(inches)
Length of Stud - RF
(inches)
Length of Stud - RTJ
(inches)
Suggested Torque
1/2 7/8 4 0.5 3 3 40
3/4 1-1/16 4 0.63 3-1/2 3-1/2 60
1 1-1/16 4 0.63 3-1/2 3-1/2 80
1-1/4 1-1/16 4 0.63 3-3/4 3-3/4 110
1-1/2 1-1/4 4 0.75 4-1/4 4-1/4 110
2 1-1/16 8 0.63 4-1/4 4-1/4 110
2-1/2 1-1/4 8 0.75 4-3/4 4-3/4 150
3 1-1/4 8 0.75 5 5 150
3-1/2 1-7/16 8 0.88 5-1/2 5-1/2 200
4 1-7/16 8 0.88 5-3/4 5-3/4 225
5 1-5/8 8 1 6-1/2 6-1/2 350
6 1-5/8 12 1 6-3/4 6-3/4 320
8 1-13/16 12 1.13 7-1/2 7-3/4 450
10 2 16 1.25 8-1/2 8-1/2 650
12 2 20 1.25 8-3/4 8-3/4 675
14 2-5/8 20 1.38 9-1/4 9-1/4 820
16 2-3/8 20 1.5 10 10 1125
18 2-9/16 20 1.63 10-3/4 10-3/4 1430
20 2-9/16 24 1.63 11-1/4 11-1/2 1400
24 2-15/16 24 1.88 13 13-1/4 2230

900 LB. Flanges

Nominal Pipe Size
(inches)
Wrench Size
(inches)
Number of Studs Diameter of Studs
(inches)
Length of Stud - RF
(inches)
Length of Stud - RTJ
(inches)
Suggested Torque
1/2 1-1/4 4 0.75 4-1/4 4-1/4 80
3/4 1-1/4 4 0.75 4-1/2 4-1/2 90
1 1-7/16 4 0.88 5 5 110
1-1/4 1-7/16 4 0.88 5 5 170
1-1/2 1-5/8 4 1 5-1/2 5-1/2 240
2 1-7/16 8 0.88 5-3/4 5-3/4 170
2-1/2 1-5/8 8 1 6-1/4 6-1/4 240
3 1-7/16 8 0.88 5-3/4 5-3/4 215
4 1-13/16 8 1.13 6-3/4 6-3/4 450
5 2 8 1.25 7-1/2 7-1/2 650
6 1-13/16 12 1.13 7-1/2 7-3/4 455
8 1-3/16 12 1.38 8-3/4 8-3/4 820
10 2-3/16 16 1.38 9-1/4 9-1/4 850
12 2-3/16 20 1.38 10 10 870
14 2-5/8 20 1.5 10-3/4 11 1125
16 2-9/16 20 1.63 11-1/4 11-1/2 1430
18 2-15/16 20 1.88 12-3/4 13-1/4 2230
20 3-1/8 20 2 13-3/4 14-1/4 2300
24 3-7/8 20 2.5 17-1/4 18 5500

1500 LB. Flanges

Nominal Pipe Size
(inches)
Wrench Size
(inches)
Number of Studs Diameter of Studs
(inches)
Length of Stud - RF
(inches)
Length of Stud - RTJ
(inches)
Suggested Torque
1/2 1-1/4 4 0.75 4-1/4 4-1/4 80
3/4 1-1/4 4 0.75 4-1/2 4-1/2 90
1 1-7/16 4 0.88 5 5 110
1-1/4 1-7/16 4 0.88 5 5 170
1-1/2 1-5/8 4 1 5-1/2 5-1/2 240
2 1-7/16 8 0.88 5-3/4 5-3/4 170
2-1/2 1-5/8 8 1 6-1/4 6-1/4 240
3 1-13/16 8 1.13 7 7 370
4 2 8 1.25 7-3/4 7-3/4 650
5 2-3/8 8 1.5 9-3/4 9-3/4 1000
6 2-3/16 12 1.38 10-1/4 10-1/2 820
8 2-9/16 12 1.63 11-1/2 12-3/4 1400
10 2-15/16 12 1.88 13-1/4 13-1/2 2100
12 3-1/8 16 2 14-3/4 15-1/4 2300
14 3-1/2 16 2.25 16 16-3/4 3400
16 3-7/8 16 2.5 17-1/2 18-1/2 4300
18 4-1/4 16 2.75 19-1/2 20-3/4 6200
20 4-5/8 16 3 21-1/4 22-1/4 7800
24 5-3/8 16 3.5 24-1/4 25-1/2 13000

2500 LB. Flanges

Nominal Pipe Size
(inches)
Wrench Size
(inches)
Number of Studs Diameter of Studs
(inches)
Length of Stud - RF
(inches)
Length of Stud - RTJ
(inches)
Suggested Torque
1/2 1-1/4 4 0.75 4-3/4 4-3/4 150
3/4 1-1/4 4 0.75 5 5 150
1 1-7/16 4 0.88 5-1/2 5-1/2 170
1-1/4 1-5/8 4 1 6 6 300
1-1/2 1-13/16 4 1.13 6-3/4 6-3/4 400
2 1-5/8 8 1 7 7 300
2-1/2 1-13/16 8 1.13 7-3/4 8 400
3 2 8 1.25 8-3/4 9 600
4 2-3/8 8 1.5 10 10-1/4 650
5 2-3/4 8 1.75 11-3/4 12-1/4 1500
6 3-1/8 8 2 13-1/2 14 2300
8 3-1/8 12 2 15 15-1/2 2400
10 3-7/8 12 2.5 19-1/4 20 4900
12 4-1/4 12 2.75 21-1/4 22 7900

About the App

Look up flange bolt sizes and torque patterns in three taps with Flange Bolt. 

Just enter the flange size, type, and class, and the tool instantly shows the ASME values for:

1. Number of studs

2. Diameter of studs

3. Length of studs

4. Torque pattern

5. Suggested torque amount

All values other than suggested torque amount are sourced directly from flange bolt charts and flange torque charts in the ASME B16.5 "Pipe Flanges and Flanged Fittings: NPS 1/2 through NPS 24 Metric/Inch Standard" (2017).

Looking up flange bolt sizes and torque patterns with Flange Bolt is far faster and less error prone than searching through PDF charts and tables. The sole purpose of the tool is to make it as simple as possible for a pipefitters, steamfitters, and others working in piping to look up flange bolt size and torque pattern information. 

Is there a feature you'd like from Flange Bolt that you don't see? Request it through the app and we'll do our best to add it to the development schedule.

Features of the app:

1. Full offline capability: No internet connection necessary to use. All data is stored locally on your phone. (The app requires minimum storage space overall)

2. Instant flange bolt sizes and torque patterns: Just enter the flange size, class, and type and the app instantly populates the correct values from the flange bolt size chart and the flange torque sequence chart, along with wrench size.

3. Flange torque sequence image: Each lookup shows the correct flange torque sequence image in picture form, with the studs numbered.

4. Suggested torque values

The information in this app covers:

(1) flanges with rating class designations 150, 300, 400, 600, 900, and 1500 in sizes NPS 1/2 through NPS 24 and flanges with rating class designation 2500 in sizes NPS 1/2 through NPS 12, with requirements given in U.S. Customary units with diameter of bolts and flange bolt holes expressed in inch units;

(2) flanged fittings with rating class designation 150 and 300 in sizes NPS 1/2 through NPS 24, with requirements given in U.S. Customary units with diameter of bolts and flange bolt holes expressed in inch units;

(3) flanged fittings with rating class designation 400, 600, 900, and 1500 in sizes NPS 1/2 through NPS 24 and flanged fittings with rating class designation 2500 in sizes NPS 1/2 through NPS 12  in U.S. Customary units.

That includes:

- 4 bolt flange pattern

- 8 bolt flange pattern

- 12 bolt flange pattern

- 16 bolt flange pattern

- 20 bolt flange pattern

- 14 bolt flange pattern