Low Fin Tube, ASME SA179 Seamless Base Tube, Cost-Effective for Feedwater Heaters

Outside Diameter
In. (mm)

Wall thickness Tolerance %

Over (+)

Under (-)

1 ½ (38.1)
and under

20

0

Over 1½ (38.1)

22

0

Outside Diameter
In. (mm)

Permissible Variations In. (mm)

Over (+)

Under (-)

Under 1 (25.4)

0.004 (0.1)

0.004 (0.1)

1 to 1 ½ (25.4 to 38.1), Incl

0.006 (0.15)

0.006 (0.15)

Over 11⁄2 to 2 [38.1 to 50.8], Excl

0.008 (0.2)

0.008 (0.2)

2 to 21⁄2 [50.8 to 63.5], Excl

0.010 (0.25)

0.010 (0.25)

21⁄2 to 3 [63.5 to 76.2], Excl

0.012 (0.3)

0.012 (0.3)

Outside Diameter

Cut Length, in.(mm)

In.(mm)

Over (+)

Under (-)

All Sizes

3⁄16 [5]

0 [0]

Under 2 [50.8]

1⁄8 [3]

0 [0]

2 [50.8] and over

3⁄16 [5]

0 [0]

Under 2 [50.8]

1⁄8 [3]

0 [0]

2 [50.8] and over

3⁄16 [5]

0 [0]

These permissible variations in length apply to tubes before bending. They apply to cut lengths up to and including 24 ft [7.3 m]. For lengths greater than 24 ft [7.3 m], the above over-tolerances shall be increased by 1⁄8 in. [3 mm] for each 10 ft [3 m] or fraction thereof over 24 ft or 1⁄2 in. [13 mm], whichever is the lesser.