SEAMLESS MECHANICAL STEEL TUBING

ASTM A519

Seamless mechanical tubing is manufactured from carbon and alloy steels for structural or other mechanical purposes involving machining or heat treating, where close tolerances, smooth finish, or definite physical properties are important factors.

Micro alloys available upon request. Reduce the weight of your product while increasing your physical requirements.

Cold Drawn Seamless stocks are generally carried to OD and ID tolerances, except when the ID is less than 50 percent of the OD. The latter sizes and hot finished seamless stocks are carried in warehouse to OD and wall tolerances.

SPECIAL NOTE: Tolerances are applicable only to two dimensions (length excepted). Thus, if OD and wall are specified, the theoretical ID may not conform to published tolerances except that the mean or average wall (taking into account the permissible OD and ID tolerances) will not vary more than indicated under “DIAMETER AND WALL TOLERANCES.”

EXAMPLE: If a cold drawn tube is specified 1-1/2 inch OD x 1-1/4 inch ID, one might expect the theoretical wall of 1/8 inch to be held to a variation of plus or minus 7-1/2 percent or within the limits of 0.116/0.134 inch.

However, for a nominal OD of 1.500 inch, the OD may vary between 1.500 inch and 1.505 inch, and the ID may vary between 1.245 inch and 1.250 inch, which may result in an average or mean wall of 0.130 inch instead of 1/8 inch. Consequently, the wall may vary plus or minus 7-1/2 percent from the mean of 0.130 inch, or within limits of 0.120/0.140 inch. If, however, the average wall were 1/8 inch (0.125) reflecting 1.500 inch OD and 1.250 inch ID, the wall limits would be plus or minus 7-1/2 percent of 1/8 or 0.116/0.134 inch. Hence, any order of tubes might vary in the entire lot as low as 0.116 inch on some and as high as 0.134 inch on others.

COMPARATIVE DATA
SEAMLESS CARBON STEELS

Condition
Nominal
Yield
Strength
psi
Nominal
Ultimate
Strength
psi
Nominal
Elongation
in 2%
Equivalent
Rockwell
Hardness
Equivalent
Brinell
Hardness
GRADE 1018
c .15/.20 Mn .60/90 P .40 max S .050 max
Hot-Rolled
 35,000
60,000
30
B-68
116
Normalized
 38,000
58,000
35
B-66
114
Soft-Annealed
 33,000
50,000
40
B-57
 97
As-Drawn
 70,000
85,000
10
B-87
170
CD-Stress Relief Annealed
 60,000
80,000
15
B-85
163
GRADE 1020
C. 18/.23 Mn .30/.60 P .040 max S .050 max
Hot-Rolled
 38,000
60,000
30
B-68
116
Normalized
 40,000
58,000
35
B-66
114
Soft-Annealed
 33,000
53,000
40
B-62
105
As-Drawn
 65,000
80,000
10
B-85
163
CD-Stress Relief Annealed
 60,000
75,000
15
B-81
149
GRADE 1026
C .22/.28 Mn .60/.90 P .030 max S .050 max
Hot-Rolled
 47,000
70,000
28
B-77
137
Normalized
 50,000
67,000
33
B-74
131
Soft-Annealed
 36,000
60,000
35
B-68
116
As-Drawn
 72,000
87,000
10
B-89
179
CD-Stress Relief Annealed
 65,000
82,000
15
B-86
167

OUTSIDE AND INSIDE DIAMETER TOLERANCES FOR
ROUND COLD-WORKED SEAMLESS TUBING PER ASTM A519

Outside
Diameter
Size Range
in
Thermal Treatment after Final Cold Work Producing Size
Wall
Thickness
as
Percent
of OD
None, or not exceeding
1100°F. Nominal
Temperature
Heated Above 1100°F. Nominal
Temperature Without
Accelerated Cooling
OD, in
ID, in
OD, in
ID, in
Over
Under
Over
Under
Over
Under
Over
Under
Up to 0.499
All
0.004
0.000
0.005
0.002
0.500-1.699
All
0.005
0.000
0.000
0.005
0.007
0.002
0.002
0.007
1.700-2.099
All
0.006
0.000
0.000
0.006
0.006
0.005
0.005
0.006
2.100-2.499
All
0.007
0.000
0.000
0.007
0.008
0.005
0.005
0.008
2.500-2.899
All
0.008
0.000
0.000
0.008
0.009
0.005
0.005
0.009
2.900-3.299
All
0.009
0.000
0.000
0.009
0.011
0.005
0.005
0.011
3.300-3.699
All
0.010
0.000
0.000
0.010
0.013
0.005
0.005
0.013
3.700-4.099
All
0.011
0.000
0.000
0.011
0.013
0.007
0.010
0.010
4.100-4.499
All
0.012
0.000
0.000
0.012
0.014
0.007
0.011
0.011
4.500-4.899
All
0.013
0.000
0.000
0.013
0.016
0.007
0.012
0.012
4.900-5.299
All
0.014
0.000
0.000
0.014
0.018
0.007
0.013
0.013
5.300-5.549
All
0.015
0.000
0.000
0.015
0.020
0.007
0.014
0.014
5.500-5.999
Under 6
6 to 7-1/2
over 7-1/2
0.010
0.010
0.010
0.010
0.018
0.018
0.018
0.018
0.009
0.009
0.009
0.009
0.016
0.016
0.016
0.016
0.018
0.000
0.009
0.009
0.017
0.015
0.016
0.016
6.000-6.499
Under 6
6 to 7-1/2
over 7-1/2
0.013
0.013
0.013
0.013
0.023
0.023
0.023
0.023
0.010
0.010
0.010
0.010
0.018
0.018
0.018
0.018
0.020
0.000
0.010
0.010
0.020
0.015
0.018
0.018
6.500-6.999
Under 6
6 to 7-1/2
over 7-1/2
0.015
0.015
0.015
0.015
0.027
0.027
0.027
0.027
0.012
0.012
0.012
0.012
0.021
0.021
0.021
0.021
0.023
0.000
0.012
0.012
0.026
0.015
0.021
0.021
7.000-7.499
Under 6
6 to 7-1/2
over 7-1/2
0.018
0.018
0.018
0.018
0.032
0.032
0.032
0.032
0.013
0.013
0.013
0.013
0.023
0.023
0.023
0.023
0.026
0.000
0.013
0.013
0.031
0.015
0.023
0.023
7.500-7.999
Under 6
6 to 7-1/2
over 7-1/2
0.020
0.020
0.020
0.020
0.035
0.035
0.035
0.035
0.015
0.015
0.015
0.015
0.026
0.026
0.026
0.026
0.029
0.000
0.015
0.015
0.036
0.015
0.026
0.026
8.000-8.499
Under 6
6 to 7-1/2
over 7 1¼2
0.023
0.023
0.023
0.023
0.041
0.041
0.041
0.041
0.016
0.016
0.016
0.016
0.028
0.028
0.028
0.028
0.031
0.000
0.015
0.016
0.033
0.022
0.028
0.028
8.500-8.999
Under 6
6 to 7-1/2
over 7-1/2
0.025
0.025
0.025
0.025
0.044
0.044
0.044
0.044
0.017
0.017
0.017
0.017
0.030
0.030
0.030
0.030
0.034
0.0000
0.015
0.019
0.038
0.022
0.030
0.030
9.000-9.499
Under 6
6 to 7-1/2
over 7-1/2
0.028
0.028
0.028
0.028
0.045
0.045
0.045
0.045
0.019
0.019
0.019
0.019
0.033
0.033
0.033
0.033
0.037
0.000
0.015
0.022
0.043
0.022
0.033
0.033
9.500-9.999
Under 6
6 to 7-1/2
over 7-1/2
0.030
0.030
0.030
0.030
0.045
0.045
0.053
0.053
0.020
0.020
0.020
0.020
0.035
0.035
0.035
0.035
0.040
0.000
0.015
0.025
0.048
0.022
0.035
0.035
10.000-10.999
Under 6
6 to 7-1/2
over 7-1/2
0.034
0.034
0.034
0.034
0.045
0.045
0.060
0.060
0.022
0.022
0.022
0.022
0.039
0.039
0.039
0.039
0.044
0.000
0.015
0.029
0.055
0.022
0.039
0.039
11.000-12.000
Under 6
6 to 7- 1/2
over 7-1/2
0.035
0.035
0.035
0.035
0.050
0.050
0.065
0.065
0.025
0.025
0.025
0.025
0.045
0.045
0.045
0.045
0.045
0.0000
0.015
0.035
0.060
0.022
0.045
0.045

WALL THICKNESS TOLERANCES FOR ROUNDa,b,c
COLD-WORKED SEAMLESS TUBING PER ASTM A519

Cold Drawn Maximum % Over
and Under Nominal
Wall Thickness
% of OD
ID Up To
1.499 Inches
ID 1.500 Inches
and Over
10
7.5
25 and Under
12.5
10
Over 2
*ID Tolerances apply to dimensions 0.625 inch and over when ID is at least half the OD
aMany tubes with inside diameter less than 50% of outside diameter or with wall thickness more than 25% of outside diameter, or with wall thickness over 11¼4 in., or weighing more than 90 lb/ft, are difficult to draw over a mandrel. Therefore, the inside diameter can vary over or under by an amount equal to 10% of the wall thickness. See also Footnote B.
bFor those tubes with inside diameter less than 1/2 in. (or less than 5/8 in. when the wall thickness is more than 20% of the outside diameter), which are not commonly drawn over a mandrel. Footnote A is not applicable. Therefore, for those tubes, the inside diameter is goverened by the outside diameter tolerance shown in thiis table and the wall thicnkess tolerances shown in Table 9.
cTubing having a wall thickness less than 3% of the outside diameter cannot be straightened properly without a certain amount of distortion. Consequently such tubes, while having an average outside diameter and inside diameter within the tolerances shown in this table, require an ovality tolerance of 1/2% over and under nominal outside diameter, this being in addition to the tolerances indicated in this table.

OVALITY OF NORMAL SIZE WILL BE WITHIN
OD TOLERANCES

For seamless tubes with inside diameter less than 1/2 inch (or less than 5/8 inch when the wall thickness is more than 20 percent of the outside diameter), which cannot be successfully drawn over a mandrel, the wall thickness may vary 15 percent over or under that specified, and the inside diameter will be governed by the outside diameter and wall thickness variations.
NOTE — Tubing having a wall thickness less than 3 percent of the outside diameter cannot be straightened properly without a certain amount of distortion. Consequently, such tubes, while having an average outside diameter and inside diameter within the tolerances shown in the preceding table, require an ovality tolerance of 1/2 percent over and under nominal outside diameter, this being in addition to the tolerances indicated in the preceding table.

VARIATIONS FROM STRAIGHTNESS

Size Limits
Maximum
Curvature
In Any
3 Feet
Maximum Curvature In
Total Lengths
Maximum
Curvature
For
Lengths
Under
3 Feet
OD 5″ and smaller, wall
thickness, over 3% of OD
but not over 0.5″
0.030
0.30 x (Number of feet/of length 3)
Ratio of
0.010″
per foot
OD over 5″ to 8″ incl. Wall
thickness, over 4% of OD
but not over 0.75″
0.045
0.045 (Number of feet/of length 3)
Ratio of
0.015″
per foot
OD over 8″ to 12″ incl. Wall
thickness, over 4% of OD 
but not over 1″
0.060
0.060″ (Number of feet/of length 3)
Ratio of
0.010″
per foot
Camber, or out-of-straightness, tolerances generally do not exceed the amounts shown for lengths of 22 feet and under. The camber is measured for any three feet of length with a three foot straightedge and the use of a feeler gage. The total camber — maximum curvature in the total length of the tube — is determined by rolling the tube on a surface plate and measuring the concavity with a feeler gage.
When the machined length of a tube extends more than three inches from the chuck or other holding mechanism, the possibility that the tube may be cambered must be taken into consideration. Allowance for camber must be made for any machined length proportional to the tolerances shown.
Tubes with lighter or heavier walls than shown, and soft annealed or hardened tubes, present more than normal straightening difficulties, and the camber tolerance requirements of such tubes usually are mutually agreed upon by the purchaser and the producer.