NFPA 13 defines a flexible coupling as; and where they should be used. Designers and installers should design their fire protection systems in compliance

“a listed coupling or fitting that allows axial displacement, with this standard. See Typical Applications – Flexible

rotation, and at least 1 degree of angular movement of the Couplings on Page 44.

pipe without inducing harm on the pipe. For pipe diameters of 8 in. and larger, the angular movement shall be permi1ed to be less than 1 degree but not less than 0.5 degrees.” (NFPA 13-2007 3.5.4)

For sprinkler systems, NFPA 13 specifies the use of flexible couplings to protect the system against damage from earthquakes and sets some specific examples of how

Axial Displacement & Angular Movement (Models XGQT2 & 1212)

Size Axial Angular Movement Size Axial Angular Movement Displace (Deflection) Displace (Deflection)

Nom.Size Actual OD -ment Per coupling Per pipe Nom.Size Actual OD -ment Per coupling Per pipe mm/in mm/in mm/in degrees mm/m, in/G mm/in mm/in mm/in degrees mm/m, in/G

20 26.7 1.6 118 150 159.0 3.2 40

6°-46ˊ 2°-18ˊ

0.75 1.050 0.0625 1.42 6 6.250 0.125 0.48

25 33.4 1.6 96 150 165.1 3.2 39

5°-30ˊ 2°-14ˊ

1 1.315 0.0625 1.16 6 6.500 0.125 0.47

32 42.4 1.6 76 150 168.3 3.2 38

4°-20ˊ 2°-10ˊ

1.25 1.660 0.0625 0.91 6 6.625 0.125 0.45

40 48.3 1.6 66 200 JIS 216.3 3.2 30

3°-48ˊ 1°-42ˊ

1.5 1.900 0.0625 0.80 8 8.516 0.125 0.36

50 60.3 1.6 53 200 219.1 3.2 29

3°-01ˊ 1°-40ˊ

2 2.375 0.0625 0.63 8 8.625 0.125 0.35

65 73 1.6 44 250 JIS 267.4 3.2 24

2°-30ˊ 1°-22ˊ

2.5 2.875 0.0625 0.52 10 10.528 0.125 0.29

65 76.1 1.6 42 250 273.0 3.2 23

2°-24ˊ 1°-20ˊ

2.5 3.000 0.0625 0.50 10 10.750 0.125 0.28

80 88.9 1.6 36 300 JIS 318.5 3.2 20

2°-04ˊ 1°-10ˊ

3 3.500 0.0625 0.43 12 12.539 0.125 0.25

90 1016 1.6 31 300 323.9 3.2 20

1°-48ˊ 1°-08ˊ

3.5 4.000 0.0625 0.38 12 12.750 0.125 0.24

100 108.0 3.2 59.0 350 355.6 3.2 18

3°-24ˊ 1°-02ˊ

4 4.25 0.125 0.71 14 14.000 0.125 0.22

100 114.3 3.2 55 400 406.4 3.2 16

3°-12ˊ 0°-54ˊ

4 4.500 0.125 0.67 16 16.000 0.125 0.19

125 127.0 3.2 50.0 450 457.0 3.2 14

2°-53ˊ 0°-48ˊ

5 5.000 0.125 0.60 18 18.000 0.125 0.17

125 133 3.2 48 500 508.0 3.2 13

2°-46ˊ 0°-44ˊ

5 5.250 0.125 0.58 20 20.000 0.125 0.15

125 139.7 3.2 46 550 559.0 3.2 11

2°-37ˊ 0°-38ˊ

5 5.500 0.125 0.55 22 22.000 0.125 0.13

125 141.3 3.2 45 600 610.0 3.2 10

2°-36ˊ 0°-36ˊ

5 5.563 0.125 0.54 24 24.000 0.125 0.13