[xml][/xml]
Piping Designer - Resources for piping, engineering and design
Jump to: navigation, search
Navigation

Additional Info

Torque Procedure

Start the tightening procedure by lubricating the nuts and bolts. Then hand tighten till they are snug against the flanges. If an air wrench is used make sure the pressure is set to the minimum. When tightening, always use the correct sequential bolt order for the flange.

4 and 8 Bolt Flanges

  • First round - 30% of final torque (flange sequential order)
  • Second round- 60% of final torque (flange sequential order)
  • Third round - 100% of final torque (flange sequential order)
  • One final time - clockwise or counter clockwise sequentially around the flange.

12 Bolt Flanges and More

  • First round - 20% of final torque (flange sequential order)
  • Second round - 40% of final torque (flange sequential order)
  • Third round - 80% of final torque (flange sequential order)
  • Fourth round - 100% of final torque (sequential order)
  • One final time - clockwise or counter clockwise sequentially around the flange.
Machine Bolt
Data
Data
One flange is marked with bolt tightening pattern

Standards

  • ASME Standards
    • ASME PCC-1 - Guidelines for Pressure Boundary Bolted Flange Joint Assembly
  • ISO Standards
    • ISO 4162 - Hexagon bolts with flange -- Small series -- Product grade A with driving feature of product grade B
    • ISO 15071 - Hexagon bolts with flange -- Small series -- Product grade A
    • ISO 15072 - Hexagon bolts with flange with metric fine pitch thread -- Small series -- Product grade A
    • ISO 21670 - Fasteners -- Hexagon weld nuts with flange

Torque Factor

Pipe Size

(NPS)

150#

(ft-lbs)

300#

(ft-lbs)

400#

(ft-lbs)

600#

(ft-lbs)

900#

(ft-lbs)

1500#

(ft-lbs)

2500#

(ft-lbs)

1/245454545150150-
3/445909090150150-
145909090240240-
1 1/4-------
1 1/245150150150368368-
290909090240240-
2 1/290150150150368368-
390150150150240533-
3 1/2-------
490150240240533750-
51501502403687501200-
61501502403685331020-
815024036853310201650-
1024036853375010203000-
1224053375075010203300-
14368533750102010204770-
163687501020102016506600-
185337501020165030008800-
2053375012001650330011580-
22-------
247501200225030006600--

4 Bolt Tightening Sequence

  • Sequential Order: 1-2, 3-4
  • Rotation Order: 1, 3, 2, 4
4 Bolt Flange

8 Bolt Tightening Sequence

  • Sequential Order: 1-2, 3-4, 5-6, 7-8
  • Rotation Order: 1, 5, 3, 7, 2, 6, 4, 8
8 Bolt Flange

12 Bolt Tightening Sequence

  • Sequential Order: 1-2, 3-4, 5-6, 7-8, 9-10, 11-12
  • Rotation Order: 1, 5, 9, 3, 7, 11, 2, 6, 10, 4, 8, 12
12 Bolt Flange

16 Bolt Tightening Sequence

  • Sequential Order: 1-2, 3-4, 5-6, 7-8, 9-10, 11-12, 13-14, 15-16
  • Rotation Order: 1, 9, 5, 13, 3, 11, 7, 15, 2, 10, 6, 14, 4, 12, 8, 16
16 Bolt Flange

20 Bolt Tightening Sequence

  • Sequential Order: 1-2, 3-4, 5-6, 7-8, 9-10, 11-12, 13-14, 15-16, 17-18, 19-20
  • Rotation Order: 1, 9, 5, 13, 3, 11, 7, 15, 2, 10, 6, 14, 4, 12, 8, 16
20 Bolt Flange

24 Bolt Tightening Sequence

  • Sequential Order: 1-2, 3-4, 5-6, 7-8, 9-10, 11-12, 13-14, 15-16, 17-18, 19-20, 21-22, 23-24
  • Rotation Order: 1, 9, 17, 5, 13, 21, 3, 11, 19, 7, 15, 23, 2, 10, 18, 6, 14, 22, 20, 8, 16, 24
24 Bolt Flange


Data shown on this page was either gathered and verified using data available in the public domain or has been calculated by the staff at Piping-Designer.com. It is up to the end user to verify data prior to use for any project. This page may not be reproduced without the explicit written permission of Piping-Designer.com.
© 2006-2015 Piping Designer, LLC