Alloy Steel Tolerances

Round Bar
Alloy(s)		Spec. Diameter, in.	Diameter Tol. (over(+)/under(-))
4130-Norm., 4140-Ann., 4340-Norm.	Cold Finish	Up to 1.5, incl.	+/- 0.004"
4130-Norm., 4140-Ann.	Cold Finish	Over 1.5 to 2.5, incl.	+/- 0.005"
4130-Norm., 4140-Ann.	Cold Finish	Over 2.5 to 4, incl.	+/- 0.006"
4130-Norm.	Cold Finish	Over 4 to 6, incl.	+/- 0.007"

Round Bar
Alloy(s)		Spec. Diameter, in.	Diameter Tol. (over(+)/under(-))
8620	Cold Finish	Up to 1.5, incl.	+/- 0.003"
8620	Cold Finish	Over 1.5 to 2.5, incl.	+/- 0.004"
8620	Cold Finish	Over 2.5 to 4, incl.	+/- 0.005"

Round Bar
Alloy(s)		Spec. Diameter, in.	Diameter Tol. (over(+)/under(-))
4340-Norm.	Hot Rolled/ Rough Turned	Over 1 to 1.125, incl.	+/- 0.010"
4340-Norm.	Hot Rolled/ Rough Turned	Over 1.125 to 1.25, incl.	+/- 0.011"
4340-Norm.	Hot Rolled/ Rough Turned	Over 1.25 to 1.375, incl.	+/- 0.012"
4340-Norm.	Hot Rolled/ Rough Turned	Over 1.375 to 1.5, incl.	+/- 0.014"
4340-Norm., 8620	Hot Rolled/ Rough Turned	Over 1.5 to 2, incl.	+/- 0.015625"
4340-Norm., 8620	Hot Rolled/ Rough Turned	Over 2 to 2.5, incl.	+ 0.03125"
4340-Norm., 8620	Hot Rolled/ Rough Turned	Over 2.5 to 3.5, incl.	+ 0.046875"
4340-Norm., 8620	Hot Rolled/ Rough Turned	Over 3.5 to 4.5, incl.	+ 0.0625"
4340-Norm., 8620	Hot Rolled/ Rough Turned	Over 4.5 to 5.5, incl.	+ 0.078125"
4340-Norm., 8620	Hot Rolled/ Rough Turned	Over 5.5 to 6.5, incl.	+ 0.125"
4340-Norm.	Hot Rolled/ Rough Turned	Over 6.5 to 8.25, incl.	+ 0.15625"
4340-Norm.	Hot Rolled/ Rough Turned	Over 8.25 to 9.5, incl.	+ 0.1875"

Round Bar
Alloy(s)		Spec. Diameter, in.	Diameter Tol. (over(+)/under(-))
4330, 4340, 9310	VAR	Up to 0.3125	+/- 0.005"
4330, 4340, 9310	VAR	Over 0.3125 to 0.4375, incl.	+/- 0.006"
4330, 4340, 9310	VAR	Over 0.4375 to 0.625, incl.	+/- 0.007"
4330, 4340, 9310	VAR	Over 0.625 to 0.875, incl.	+/- 0.008"
4330, 4340, 9310	VAR	Over 0.875 to 1.000, incl.	+/- 0.009"
4330, 4340, 9310	VAR	Over 1.000 to 1.125, incl.	+/- 0.010"
4330, 4340, 9310	VAR	Over 1.125 to 1.250, incl.	+/- 0.011"
4330, 4340, 9310	VAR	Over 1.250 to 1.375, incl.	+/- 0.012"
4330, 4340, 9310	VAR	Over 1.375 to 1.500, incl.	+/- 0.014"
4330, 4340, 9310	VAR	Over 1.500 to 2.000, incl.	+/- 0.016"
4330, 4340, 9310	VAR	Over 2.000 to 2.500, incl.	+ 0.031"
4330, 4340, 9310	VAR	Over 2.500 to 3.500, incl.	+ 0.047"
4330, 4340, 9310	VAR	Over 3.500 to 4.500, incl.	+ 0.063"
4330, 4340, 9310	VAR	Over 4.500 to 5.500, incl.	+ 0.078"
4330, 4340, 9310	VAR	Over 5.500 to 6.500, incl.	+ 0.125"
4330, 4340, 9310	VAR	Over 6.500 to 8.250, incl.	+ 0.156"
4330, 4340, 9310	VAR	Over 8.250 to 9.500, incl.	+ 0.188"
4330, 4340, 9310	VAR	Over 9.500 ot 10.000, incl.	+ 0.250"

Metric Round Bar
Alloy(s)		Spec. Dia., mm	Dia. Tol. (over(+)/under(-))
4140 metric	Ann. TGP	6mm to 42mm	+ 0/- 0.0005″ (.0127mm)
4140 metric	Ann. TGP	45mm to 60mm	+ 0/- 0.00075″ (.0191mm)

Straightness Tolerance - Cold Finished Round Bar
Alloy(s)		Spec. Dia., in.	Max. Deviation from Straightness
4130, 4140, 4340	Cold Finished	Less than 0.625	1/8"
4130, 4140, 4340	Cold Finished	0.625 and over	1/16"
8620	Cold Finished	Less than 0.625	3/16"
8620	Cold Finished	0.625 and over	1/8"
Straightness tolerance will be void once full length is cut

Straightness Tolerance - Hot Rolled Round Bar
Alloy(s)		Permissible Variations from Straight
4130, 4140, 4140/4142	Hot Rolled	0.25" in any 5 ft and (0.25" × length in ft)/5
Straightness tolerance will be void once full length is cut

Square Bar
Alloy(s)		Spec. Sq., in.	Sq. Tol. (over(+)/under(-))	Spec. Length	Length Tol. (over(+)/under(-))
4142	Pre- hard	All Sizes	+/- 0.001"	18"	+ 0.125" to 0.25"
4142	Pre- hard	All Sizes	+/- 0.001"	36"	+ 0.25" to 0.50"
4142	Pre- hard	All Sizes	+/- 0.001"	72"	+ 1.00"/- 0"

Hex Bar
Alloy(s)		Spec. Across Flats	Across Flats Tol. (over(+)/under(-))
4130	Cold Drawn Normalized	Up to 0.500, incl.	+/- 0.007"
4130	Cold Drawn Normalized	Over 0.500 to 1.000, incl.	+/- 0.010"
4130	Cold Drawn Normalized	Over 1.000 to 1.500, incl.	+ 0.021"/- 0.013"
4130	Cold Drawn Normalized	Over 1.500 to 2.000, incl.	+ 0.03125"/- 0.015625"

Hex Bar
Alloy(s)		Spec. Across Flats	Across Flats Tol. (over(+)/under(-))
4140/4142	Cold Finish	Up to 0.750, incl.	+/- 0.004"
4140/4142	Cold Finish	Over 0.750 to 1.500, incl.	+/- 0.005"
4140/4142	Cold Finish	Over 1.500 to 2.500, incl.	+/- 0.006"
4140/4142	Cold Finish	Over 2.500 to 3.125, incl.	+/- 0.007"

Metric Hex Bar
Alloy(s)		Spec. Across Flats	Across Flats Tol. (over(+)/under(-))
4140 metric	Quench Tempered/ Stress Relieved	> 3mm to ≤ 6mm	+ 0/- 0.075mm
4140 metric	QT/SR	> 6mm to ≤ 10mm	+ 0/- 0.090mm
4140 metric	QT/SR	> 10mm to ≤ 18mm	+ 0/- 0.110mm
4140 metric	QT/SR	> 18mm to ≤ 30mm	+ 0/- 0.130mm
4140 metric	QT/SR	> 30mm to ≤ 50mm	+ 0/- 0.160mm

Straightness Tolerance - Cold Finished Hex Bar
Alloy(s)		Spec. Dia., in.	Max. Deviation from Straightness
4130, 4140, 4140/4142	Cold Finished	Less than 0.625	1/8"
4130, 4140, 4140/4142	Cold Finished	0.625 and over	1/16"
Straightness tolerance will be void once full length is cut

Rectangle Bar
Alloy(s)		Spec. Thick, in.	Thick Tol. (over(+)/under(-))	Spec. Width, in.	Width Tol. (over(+)/under(-))
4142	Pre-hard	Any	+/- 0.001"	Any	+ 0.000" to + 0.005"

Rectangle Bar
Alloy(s)		Spec. Width, in.	Width & Thick Tol. (over(+)/under(-))
4340	Cold Drawn	Up to 0.75, incl.	+/- 0.004"
4340	Cold Drawn	Over 0.75 to 1.5, incl.	+/- 0.005"
4340	Cold Drawn	Over 1.5 to 3, incl.	+/- 0.006"
4340	Cold Drawn	Over 3 to 4, incl.	+/- 0.008"
4340	Cold Drawn	Over 4 to 6, incl.	+/- 0.010"

Rectangle Bar
			Permissible Variations in Thickness, for Thickness Given, in. (over(+)/under(-))
Alloy(s)		Spec. Width, in.	0.230 to 0.250, excl.	0.250 to 0.500, incl.	Over 0.500 to 1, incl.	Over 1 to 2, incl.	Over 2 to 3, incl.	Over 3	Width Tol.
4140 HT, 4340	Hot Rolled	Over 1 to 2, incl.	+/- 0.007"	+/- 0.008"	+/- 0.010"	...	...	...	+/- 0.15625"
4140 HT, 4340	Hot Rolled	Over 1 to 2, incl.	+/- 0.007"	+/- 0.012"	+/- 0.015"	+/- 0.03125"	...	...	+/- 0.03125"
4140 HT, 4340	Hot Rolled	Over 2 to 4, incl.	+/- 0.008"	+/- 0.015"	+/- 0.020"	+/- 0.03125"	+/- 0.046875"	+/- 0.046875"	+ 0.0625", - 0.03125"
4140 HT, 4340	Hot Rolled	Over 4 to 6, incl.	+/ 0.009"	+/- 0.015"	+/- 0.020"	+/- 0.03125"	+/- 0.046875"	+/- 0.046875"	+ 0.09375", - 0.0625"
4140 HT, 4340	Hot Rolled	Over 6 to 8, incl.	+/- 0.015"	+/- 0.016"	+/- 0.025"	+/- 0.03125"	+/- 0.046875"	+/- 0.0625"	+ 0.125", - 0.09375"

Sheet/Plate
Alloy(s)		Spec. Thick, in.	Thick Tol. (over(+)/under(-))
4130 Annealed/ Normalized	Cold Rolled	0.025	+/- 0.005"
4130 Annealed/ Normalized	Cold Rolled	0.032	+/- 0.005"
4130 Annealed/ Normalized	Cold Rolled	0.040	+/- 0.009"
4130 Annealed/ Normalized	Cold Rolled	0.050	+/- 0.009"
4130 Annealed/ Normalized	Cold Rolled	0.063	+/- 0.009"
4130 Annealed/ Normalized	Cold Rolled	0.071	+/- 0.009"
4130 Annealed/ Normalized	Cold Rolled	0.080	+/- 0.009"
4130 Annealed/ Normalized	Cold Rolled	0.090	+/- 0.009"
4130 Annealed/ Normalized	Cold Rolled	0.100	+/- 0.009"
4130 Annealed/ Normalized	Cold Rolled	0.125	+/- 0.009"
4130 Annealed/ Normalized	Cold Rolled	0.160	+/- 0.009"
4130 Annealed/ Normalized	Hot Rolled	0.190	+/- 0.009"

Sheet/Plate
Alloy(s)		Spec. Thick, in.	Thick Tol. (over(+)/under(-))
4340 Annealed	Hot Rolled	Up to 0.5, excl.	+ 0.03"/- 0.01"
4340 Annealed	Hot Rolled	0.5 to 0.625, excl.	+ 0.03"/- 0.01"
4340 Annealed	Hot Rolled	0.625 to 0.75, excl.	+ 0.03"/- 0.01"
4340 Annealed	Hot Rolled	0.75 to 1, excl.	+ 0.03"/- 0.01"
4340 Annealed	Hot Rolled	1 to 2, excl.	+ 0.06"/- 0.01"
4340 Annealed	Hot Rolled	2 to 3, excl.	+ 0.09"/- 0.01"
4340 Annealed	Hot Rolled	3 to 4, excl.	+ 0.11"/- 0.01"
4340 Annealed	Hot Rolled	4 to 6, excl.	+ 0.15"/- 0.01"
4340 Annealed	Hot Rolled	6 to 10, excl.	+ 0.24"/- 0.01"

Round Tubes
Alloy(s)		Spec. O.D., in.	O.D. Tol. (over(+)/under(-))
4130-N	Cold Drawn/ Seamless	Up to 0.499	+ 0.005"/- 0.002"
4130-N	Cold Drawn/ Seamless	0.500 to 1.699	+ 0.007"/- 0.002"
4130-N	Cold Drawn/ Seamless	1.700 to 2.099	+ 0.006"/- 0.005"
4130-N	Cold Drawn/ Seamless	2.100 to 2.499	+ 0.008"/- 0.005"
4130-N	Cold Drawn/ Seamless	2.500 to 2.899	+ 0.009"/- 0.005"
4130-N	Cold Drawn/ Seamless	2.900 to 3.299	+ 0.011"/- 0.005"
4130-N	Cold Drawn/ Seamless	3.300 to 3.699	+ 0.013"/- 0.005"
4130-N	Cold Drawn/ Seamless	3.700 to 4.099	+ 0.013"/- 0.007"
4130-N	Cold Drawn/ Seamless	4.100 to 4.499	+ 0.014"/- 0.007"
4130-N	Cold Drawn/ Seamless	4.500 to 4.899	+ 0.016"/- 0.007"
4130-N	Cold Drawn/ Seamless	4.900 to 5.299	+ 0.018"/- 0.007"
4130-N	Cold Drawn/ Seamless	5.300 to 5.549	+ 0.020"/- 0.007"

Round Tubes
			Wall Tol. (over(+)/under(-))
Alloy(s)		Wall Thick % of OD	Spec. I.D. Under 0.500"	Spec. I.D 0.500" and Over
4130-N	Cold Drawn / Smls.	Under 10%	+/- 10%	+/- 7.5%
4130-N	Cold Drawn / Smls.	10 to 25%	+/- 10%	+/- 6.0%
4130-N	Cold Drawn / Smls.	Over 25%	+/- 12.5%	+/- 7.5%

Metric Round Tubes
Alloy(s)		Spec. O.D., mm	O.D. Tol. (over(+)/under(-))
4140 Metric	Cold Drawn/ TGP	8mm to 30mm	+/- 0.08mm
4140 Metric	Cold Drawn/ TGP	40mm	+/- 0.15mm
		Spec. Wall Thickness, mm	Wall Tol. (over(+)/under(-))
4140 Metric	Cold Drawn/ TGP	Any	+/- 10% or +/- 0.1mm (which ever value is greater)

Straightness Tolerance - Seamless Round Tube
Alloy(s)		Size	Max. Curvature in any 3 ft.	Max. Curvature in Total Lengths
4130 & 4140	Seamless	Up to 5" OD & Wall thick. over 3% of OD but not over 0.5"	0.030"	0.030 x (Number of feet/of length 3)
4130 & 4140	Seamless	Over 5" to 8" incl. OD & Wall thick. over 4% of OD but not over 0.75"	0.045"	0.045 x (Number of feet/of length 3)
4130 & 4140	Seamless	Over 8" to 12" incl. OD & Wall thick. over 4% of OD but not over 1"	0.060"	0.060 x (Number of feet/of length 3)
Straightness tolerance will be void once full length is cut

Grade	Sphericity		Dia. Tolerance per Container/Lot		Diameter Tolerance Per Shipment		Surface Roughness, Ra
Balls
Grade	Inches	MM	Inches	MM	Inches	MM	µinch	µm
10	0.00001	0.0002	0.00002	0.0005	±0.0001	±0.00254	1	0.025
15	0.00001	0.0004	0.00003	0.0007	±0.0001	±0.00254	1	0.025
25	0.000025	0.0006	0.00005	0.0013	±0.0001	±0.00254	2	0.05
50	0.00005	0.0013	0.0001	0.0025	±0.0002	±0.0050	3	0.08
100	0.0001	0.0025	0.0002	0.0050	±0.0005	±0.0127	5	0.125
200	0.0002	0.0051	0.0004	0.0102	±0.0010	±0.0254	8	0.2
300	0.0003	0.0076	0.0006	0.0152	±0.0015	±0.0381	n/a	n/a
500	0.0005	0.0127	0.001	0.025	±0.002	±0.050	n/a	n/a
1000	0.0010	0.0254	0.002	0.051	±0.005	±0.127	n/a	n/a
2000	n/a	n/a	0.005	0.127	±0.005	±0.127	n/a	n/a
Burnishing	n/a	n/a	n/a	n/a	±0.005	±0.127	n/a	n/a

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Alloy Steel Tolerances