In the selection of an expansion joint, one of the critical design factors is the thermal expansion. To compute the linear expansion of a straight run of pipe or ducting, the designer must select the material and determine the linear distance of the ductwork. The linear expansion of the ductwork can be determined from the thermal growth chart using the temperature change between ambient and the design temperature.

Thermal Growth Chart

Temp. F. Temp. C. Carbon, C MO, 3CR MO Steel 5 Cr Mo
thru
9 Cr Mo 18
Austen, Stainless Steel Ferritic Stainless Steel Monel 400 Inconel 600 25CR 20NI
-325 -198 -2.37 (-1.97) -2.22 (-1.85) -3.85 (-3.21) -2.04 (-1.70) -2.62 (-2.18) -3.00 (-2.50)
-300 -184 -2.24 (-1.87) -2.10 (-1.75) -3.62 (-3.02) -1.93 (-1.61) -2.50 (-2.08) -2.83 (-2.36)
-275 -171 -2.11 (-1.76) -1.98 (-1.65) -3.40 (-2.83) -1.81 (-1.51) -2.38 (-1.98) -2.66 (-2.22)
-250 -157 -1.98 (-1.65) -1.86 (-1.55) -3.17 (-2.64) -1.70 (-1.42) -2.26 (-1.88) -2.30 (-1.92) -2.49 (-2.07)
-225 -143 -1.84 (-1.53) -1.74 (-1.45) -2.95 (-2.46) -1.58 (-1.32) -2.14 (-1.78) -2.17 (-1.81) -2.32 (-1.93)
-200 -129 -1.71 (-1.42) -1.62 (-1.35) -2.72 (-2.27) -1.47 (-1.22) -2.03 (-1.69) -2.04 (-1.70) -2.15 (-1.79)
-175 -115 -1.58 (-1.32) -1.50 (-1.25) -2.49 (-2.07) -1.35 (-1.12) -1.91 (-1.59) -1.87 (-1.56) -1.98 (-1.65)
-150 -101 -1.45 (-1.21) -1.37 (-1.14) -2.27 (-1.89) -1.24 (-1.03) -1.79 (-1.49) -1.70 (-1.42) -1.81 (-1.51)
-125 -87 -1.30 (-1.08) -1.23 (-1.02) -2.01 (-1.67) -1.12 (-0.93) -1.59 (-1.32) -1.54 (-1.28) -1.60 (-1.33)
-100 -73 -1.15 (-0.96) -1.08 (-0.90) -1.75 (-1.46) -0.99 (-0.82) -1.38 (-1.15) -1.37 (-1.14) -1.39 (-1.16)
-75 -59 -1.00 (-0.83) -0.94 (-0.78) -1.50 (-1.25) -0.86 (-0.72) -1.18 (-0.98) -1.17 (-0.97) -1.19 (-0.99)
-50 -46 -0.84 (-0.70) -0.79 (-0.66) -1.24 (-1.03) -0.72 (-0.60) -0.98 (-0.82) -0.97 (-0.81) -0.98 (-0.82)
-25 -32 -0.67 (-0.56) -0.63 (-0.52) -0.98 (-0.82) -0.58 (-0.48) -0.77 (-0.64) -0.76 (-0.63) -0.76 (-0.63)
0 -18 -0.50 (-0.42) -0.46 (-0.38) -0.72 (-0.60) -0.43 (-0.36) -0.57 (-0.47) -0.56 (-0.47) -0.57 (-0.47)
25 -4 -0.32 (-0.27) -0.30 (-0.25) -0.46 (-0.38) -0.27 (-0.22) -0.37 (-0.31) -0.36 (-0.30) -0.37 (-0.31)
50 10 -0.14 (-0.12) -0.13 (-0.11) -0.21 (-0.17) -0.12 (-0.10) -0.16 (-0.13) -0.16 (-0.13) -0.16 (-0.13)
70 24 0.00 (0.00) 0 (0.00) 0.00 (0.00) 0.00 (0.00) 0.00 (0.00) 0.00 (0.00) 0.00 (0.00)
100 38 0.22 (0.18) 0.22 (0.18) 0.33 (0.27) 0.19 (0.16) 0.27 (0.22) 0.26 (0.22) 0.27 (0.22)
125 52 0.41 (0.34) 0.40 (0.33) 0.61 (0.51) 0.35 (0.29) 0.50 (0.42) 0.48 (0.40) 0.50 (0.42)
150 66 0.60 (0.50) 0.58 (0.48) 0.89 (0.74) 0.52 (0.43) 0.74 (0.62) 0.70 (0.58) 0.73 (0.61)
175 79 0.80 (0.67) 0.76 (0.63) 1.17 (0.97) 0.69 (0.57) 0.98 (0.82) 0.93 (0.77) 0.97 (0.81)
200 93 1.00 (0.83) 0.94 (0.78) 1.46 (1.22) 0.86 (0.72) 1.22 (1.02) 1.15 (0.96) 1.21 (1.01)
225 107 1.20 (1.00) 1.13 (0.94) 1.74 (1.45) 1.03 (0.86) 1.47 (1.22) 1.39 (1.16) 1.45 (1.21)
250 121 1.40 (1.17) 1.33 (1.11) 2.03 (1.69) 1.21 (1.01) 1.71 (1.42) 1.63 (1.36) 1.69 (1.41)
275 135 1.61 (1.34) 1.52 (1.27) 2.32 (1.93) 1.38 (1.15) 1.96 (1.63) 1.86 (1.55) 1.94 (1.62)
300 149 1.82 (1.52) 1.71 (1.42) 2.61 (2.17) 1.56 (1.30) 2.21 (1.84) 2.10 (1.75) 2.19 (1.82)
325 163 2.04 (1.70) 1.90 (1.58) 2.91 (2.42) 1.74 (1.45) 2.47 (2.06) 2.34 (1.95) 2.44 (2.03)
350 177 2.25 (1.87) 2.10 (1.75) 3.20 (2.67) 1.93 (1.61) 2.72 (2.27) 2.57 (2.14) 2.69 (2.24)
375 191 2.48 (2.07) 2.30 (1.92) 3.50 (2.92) 2.11 (1.76) 2.98 (2.48) 2.81 (2.34) 2.94 (2.45)
400 204 2.70 (2.25) 2.50 (2.08) 3.80 (3.17) 2.30 (1.92) 3.25 (2.71) 3.05 (2.54) 3.20 (2.67)
425 218 2.93 (2.44) 2.72 (2.27) 4.10 (3.42) 2.49 (2.07) 3.51 (2.92) 3.30 (2.75) 3.46 (2.88)
450 232 3.16 (2.63) 2.93 (2.44) 4.40 (3.67) 2.68 (2.23) 3.78 (3.15) 3.54 (2.95) 3.72 (3.10)
475 246 3.39 (2.82) 3.14 (2.62) 4.70 (3.92) 2.88 (2.40) 4.06 (3.38) 3.79 (3.16) 3.98 (3.32)
500 260 3.62 (3.02) 3.35 (2.79) 5.01 (4.17) 3.08 (2.57) 4.33 (3.61) 4.03 (3.36) 4.24 (3.53)
525 274 3.86 (3.22) 3.58 (2.98) 5.31 (4.42) 3.28 (2.73) 4.61 (3.84) 4.28 (3.57) 4.51 (3.76)
550 288 4.10 (3.42) 3.80 (3.17) 5.62 (4.68) 3.48 (2.90) 4.89 (4.07) 4.53 (3.77) 4.78 (3.98)
575 302 4.35 (3.62) 4.02 (3.35) 5.93 (4.94) 3.69 (3.07) 5.17 (4.31) 4.77 (3.97) 5.05 (4.21)
600 316 4.60 (3.83) 4.24 (3.53) 6.24 (5.20) 3.90 (3.25) 5.46 (4.55) 5.02 (4.18) 5.33 (4.44)
625 329 4.85 (4.04) 4.47 (3.72) 6.56 (5.46) 4.10 (3.42) 5.75 (4.79) 5.29 (4.41) 5.60 (4.66)
650 343 5.11 (4.26) 4.69 (3.91) 6.87 (5.72) 4.31 (3.59) 6.04 (5.03) 5.54 (4.61) 5.88 (4.90)
675 357 5.36 (4.46) 4.92 (4.10) 7.18 (5.98) 4.52 (3.77) 6.34 (5.28) 5.80 (4.83) 6.16 (5.13)
700 371 5.62 (4.68) 5.14 (4.28) 7.50 (6.25) 4.73 (3.94) 6.64 (5.53) 6.06 (5.05) 6.44 (5.36)
725 385 5.89 (4.91) 5.38 (4.48) 7.82 (6.51) 4.95 (4.12) 6.94 (5.78) 6.32 (5.26) 6.73 (5.61)
750 399 6.16 (5.13) 5.62 (4.68) 8.15 (6.79) 5.16 (4.30) 7.24 (6.03) 6.58 (5.48) 7.02 (5.85)
775 413 6.43 (5.36) 5.86 (4.88) 8.47 (7.06) 5.38 (4.48) 7.54 (6.28) 6.84 (5.70) 7.31 (6.09)
800 427 6.70 (5.58) 6.10 (5.08) 8.80 (7.33) 5.60 (4.66) 7.85 (6.54) 7.10 (5.91) 7.60 (6.33)
825 441 6.97 (5.81) 6.34 (5.28) 9.13 (7.61) 5.82 (4.85) 8.16 (6.80) 7.38 (6.15) 7.89 (6.57)
850 454 7.25 (6.04) 6.59 (5.49) 9.46 (7.88) 6.04 (5.03) 8.48 (7.06) 7.67 (6.39) 8.19 (6.82)
875 468 7.53 (6.27) 6.83 (5.69) 9.79 (8.16) 6.27 (5.22) 8.80 (7.33) 7.95 (6.62) 8.48 (7.06)
900 482 7.81 (6.51) 7.07 (5.89) 10.12 (8.43) 6.49 (5.41) 9.12 (7.60) 8.23 (6.86) 8.78 (7.31)
925 496 8.08 (6.73) 7.31 (6.09) 10.46 (8.71) 6.72 (5.60) 9.44 (7.86) 8.52 (7.10) 9.07 (7.56)
950 510 8.35 (6.96) 7.56 (6.30) 10.80 (9.00) 6.94 (5.78) 9.77 (8.14) 8.80 (7.33) 9.36 (7.80)
975 524 8.62 (7.18) 7.81 (6.51) 11.14 (9.28) 7.17 (5.97) 10.09 (8.40) 9.09 (7.57) 9.66 (8.05)
1000 538 8.89 (7.41) 8.06 (6.71) 11.48 (9.56) 7.40 (6.16) 10.42 (8.68) 9.37 (7.81) 9.95 (8.29)
1025 552 9.18 (7.65) 8.30 (6.91) 11.82 (9.85) 7.62 (6.35) 10.76 (8.96) 9.66 (8.05) 10.25 (8.54)
1050 566 9.46 (7.88) 8.55 (7.12) 12.16 (10.13) 7.85 (6.54) 11.09 (9.24) 9.94 (8.28) 10.54 (8.78)
1075 579 9.75 (8.12) 8.80 (7.33) 12.50 (10.41) 8.08 (6.73) 11.43 (9.52) 10.23 (8.52) 10.83 (9.02)
1100 593 10.04 (8.36) 9.05 (7.54) 12.84 (10.70) 8.31 (6.92) 11.77 (9.80) 10.51 (8.75) 11.12 (9.26)
1125 607 10.30 (8.58) 9.28 (7.73) 13.18 (10.98) 8.53 (7.11) 12.11 (10.09) 10.80 (9.00) 11.42 (9.51)
1150 621 10.57 (8.80) 9.52 (7.93) 13.52 (11.26) 8.75 (7.29) 12.45 (10.37) 11.09 (9.24) 11.72 (9.76)
1175 635 10.84 (9.03) 9.76 (8.13) 13.87 (11.55) 8.97 (7.47) 12.80 (10.66) 11.37 (9.47) 12.01 (10.00)
1200 649 11.10 (9.25) 10.00 (8.33) 14.20 (11.83) 9.19 (7.66) 13.15 (10.95) 11.66 (9.71) 12.31 (10.25)
1225 663 11.38 (9.48) 10.26 (8.55) 14.55 (12.12) 9.42 (7.85) 13.51 (11.25) 11.98 (9.98) 12.60 (10.50)
1250 677 11.66 (9.71) 10.53 (8.77) 14.88 (12.40) 9.65 (8.04) 13.86 (11.55) 12.29 (10.24) 12.89 (10.74)
1275 691 11.94 (9.95) 10.79 (8.99) 15.22 (12.68) 9.88 (8.23) 14.22 (11.85) 12.61 (10.50) 13.17 (10.97)
1300 704 12.22 (10.18) 11.06 (9.21) 15.56 (12.96) 10.11 (8.42) 14.58 (12.15) 12.93 (10.77) 13.46 (11.21)
1325 718 12.50 (10.41) 11.30 (9.41) 15.90 (13.24) 10.33 (8.60) 14.94 (12.45) 13.25 (11.04) 13.76 (11.46)
1350 732 12.78 (10.65) 11.55 (9.62) 16.24 (13.53) 10.56 (8.80) 15.30 (12.74) 13.56 (11.30) 14.05 (11.70)
1375 746 13.06 (10.88) 11.80 (9.83) 16.58 (13.81) 10.79 (8.99) 15.66 (13.04) 13.88 (11.56) 14.35 (11.95)
1400 760 13.34 (11.11) 12.05 (10.04) 16.92 (14.09) 11.01 (9.17) 16.02 (13.34) 14.20 (11.83) 14.65 (12.20)