Torque Values for 3-Flow, Inc.
Sealing Gasket/Flange Isolation Kits

The following torque values apply to DEFENDER FS gaskets only.

3-Flow, Inc. does not take responsibility for any of these torque values. They're theoretical values. These bolt torque values are intended for use as guidelines only and are based on ideal conditions, perfect flanges, flange alignment and new well lubricated bolts/nuts according to the National Boiler Code, installed in accordance with the proper tools and installation guide. Torque values are based on using weld-neck flanges and lubricated stud bolts with a 0.17 friction factor.

ASME B16.5 Flanges Pressure Class 150

NPS
(Inches)

Qty. Bolts

Bolt Diameter

Torque (Ft. Lbs.)
k=0.17

1/2

4

0.5

28

3/4

4

0.5

30

1

4

0.5

28

1-1/4

4

0.5

34

1-1/2

4

0.5

45

2

4

0.625

89

2-1/2

4

0.625

121

3

4

0.625

134

3-1/2

8

0.625

107

4

8

0.625

134

5

8

0.75

208

6

8

0.75

241

8

8

0.75

241

10

12

0.875

369

12

12

0.875

390

14

12

1.0

570

16

16

1.0

570

18

16

1.125

835

20

20

1.125

731

22

20

1.125

460

24

20

1.25

987


ASME B16.5 Flanges Pressure Class 300

NPS
(Inches)

Qty. Bolts

Bolt Diameter

Torque (Ft. Lbs.)
k=0.17

1/2

4

0.625

28

3/4

4

0.625

57

1

4

0.625

57

1-1/4

4

0.625

57

1-1/2

4

0.75

103

2

8

0.75

57

2-1/2

8

0.625

103

3

8

0.75

115

3-1/2

8

0.75

119

4

8

0.75

164

5

8

0.75

221

6

12

0.75

192

8

12

0.875

322

10

16

1.00

343

12

16

1.125

464

14

20

1.125

406

16

20

1.25

592

18

24

1.25

642

20

24

1.25

674

24

24

1.50

1015


ASME B16.5 Flanges Pressure Class 600

NPS
(Inches)

Qty. Bolts

Bolt Diameter

Torque (Ft. Lbs.)
k=0.17

1/2

4

0.625

28

3/4

4

0.625

57

1

4

0.625

57

1-1/4

4

0.625

57

1-1/2

4

0.75

103

2

8

0.625

57

2-1/2

8

0.75

103

3

8

0.75

115

3-1/2

8

0.875

119

4

8

0.875

192

5

8

0.875

297

6

12

1.00

192

8

12

1.125

417

10

16

1.25

526

12

20

1.25

526

14

20

1.375

720

16

20

1.50

955

18

20

1.625

1238

20

24

1.625

1238

24

24

1.875

1958


ASME B16.5 Flanges Pressure Class 900

NPS
(Inches)

Qty. Bolts

Bolt Diameter

Torque (Ft. Lbs.)
k=0.17

1/2

4

0.875

103

3/4

4

0.875

103

1

4

0.875

166

1-1/4

4

0.875

166

1-1/2

4

1.00

250

2

8

0.875

166

2-1/2

8

1.00

250

3

8

0.875

166

4

8

1.250

371

5

8

1.250

526

6

12

1.125

371

8

12

1.375

720

10

16

1.375

720

12

20

1.375

720

14

20

1.50

955

16

20

1.625

1238

18

20

1.875

1958

20

20

2.00

2404

24

20

2.50

4863


ASME B16.5 Flanges Pressure Class 1500

NPS
(Inches)

Qty. Bolts

Bolt Diameter

Torque (Ft. Lbs.)
k=0.17

1/2

4

0.875

103

3/4

4

0.875

103

1

4

0.875

166

1-1/4

4

0.875

166

1-1/2

4

1.00

250

2

8

0.875

166

2-1/2

8

1.00

250

3

8

1.125

371

4

8

1.250

526

5

8

1.50

955

6

12

1.375

720

8

12

1.625

1238

10

12

1.875

1958

12

16

2.00

2404

14

16

2.25

3490

16

16

2.50

4863

18

16

2.75

6555

20

16

3.00

8601

24

16

3.50

11879


ASME B16.5 Flanges Pressure Class 2500

NPS
(Inches)

Qty. Bolts

Bolt Diameter

Torque (Ft. Lbs.)
k=0.17

1/2

4

0.750

103

3/4

4

0.750

103

1

4

0.875

166

1-1/4

4

1.00

250

1-1/2

4

1.125

371

2

8

1.00

250

2-1/2

8

1.125

371

3

8

1.250

526

4

8

1.500

955

5

8

1.750

1570

6

8

2.00

2404

8

12

2.00

2404

10

12

2.50

4863

12

12

2.75

6350

Additional Links

Material Property Information
Specifications in Word Document Format
Literature
Ordering Guide
Locate a Stocking Distributor and 3-Flow, Inc. Representative
Home



3-Flow, Inc.
14998 West 6th Avenue, Suite 600
Golden, CO 80401 U.S.A.
Tel: 720-479-8448
Toll Free: 877-848-3435
Fax: 720-328-8121