ASTM A125-96(2001)

Standard Specification for Steel Springs, Helical, Heat-Treated

SCOPE
1.1 This specification covers hot-coiled, heat-treated helical compression springs with tapered, closed, squared and ground ends made of hot-wrought round steel bars 3/8 in. (9.5 mm) and larger in diameter.  
1.2 This specification also serves to inform the user of practical manufacturing limits, mechanical tests, and inspection requirements applicable to the type of spring described in 1.1.  
1.3 Supplementary Requirements S1 to S8 inclusive of an optional nature are provided. They shall apply only when specified by the purchaser. Details of these supplementary requirements shall be agreed upon by the manufacturer and purchaser.  
1.4 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.

General Information

• Status: Historical
• Publication Date: 24-Jan-1996
• ICS: 21.160 - Springs
• Technical Committee: A01 - Steel, Stainless Steel and Related Alloys
• Drafting Committee: A01.15 - Bars

Relations

• Replaces: ASTM A125-96 - Standard Specification for Steel Springs, Helical, Heat-Treated
• Effective Date: 25-Jan-1996
• Replaced By: ASTM A125-96(2007) - Standard Specification for Steel Springs, Helical, Heat-Treated
• Effective Date: 01-Mar-2007
• Referred By: ASTM F1370-92(2019)e1 - Standard Specification for Pressure-Reducing Valves for Water Systems, Shipboard
• Effective Date: 25-Jan-1996
• Referred By: ASTM F1508-96(2021) - Standard Specification for Angle Style, Pressure Relief Valves for Steam, Gas, and Liquid Services
• Effective Date: 25-Jan-1996
• Referred By: ASTM D3535-07a(2021) - Standard Test Method for Resistance to Creep Under Static Loading for Structural Wood Laminating Adhesives Used Under Exterior Exposure Conditions
• Effective Date: 25-Jan-1996

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn. Contact ASTM
International (www.astm.org) for the latest information.
Designation: A 125 – 96 (Reapproved 2001)
Standard Specification for
Steel Springs, Helical, Heat-Treated
This standard is issued under the fixed designation A 125; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
1. Scope 3.1.3 A drawing or list showing required dimensions and
loads, and part number,
1.1 This specification covers hot-coiled, heat-treated helical
3.1.4 Packaging, marking and loading, and
compression springs with tapered, closed, squared and ground
3.1.5 End use.
endsmadeofhot-wroughtroundsteelbars ⁄8 in.(9.5mm)and
larger in diameter.
NOTE 1—A typical ordering description is: 500 springs Drawing 3303
1.2 This specification also serves to inform the user of
Rev. A. to ASTM A 125, 1095 steel, for cyclical machine operation.
Palletize, maximum weight 4000 lb.
practical manufacturing limits, mechanical tests, and inspec-
tion requirements applicable to the type of spring described in
4. Materials and Manufacture
1.1.
4.1 Material:
1.3 Supplementary Requirements S1 to S8 inclusive of an
4.1.1 Unless otherwise specified, the springs shall be made
optional nature are provided. They shall apply only when
of carbon steel bars conforming to the requirements of Speci-
specified by the purchaser. Details of these supplementary
ficationA689.Duetohardenabilitylimitationsofcarbonsteel,
requirements shall be agreed upon by the manufacturer and
it is suggested that the bar diameter be limited to 1 ⁄8 in. (41.8
purchaser.
mm) max in order to withstand the maximum test stress
1.4 The values stated in inch-pound units are to be regarded
requirements of this specification.
as the standard. The values given in parentheses are for
4.1.2 If alloy steel is specified, the springs shall be made
information only).
from alloy steel bars conforming to Specification A689. Any
2. Referenced Documents
of the alloy steel grades referred to may be used at the option
of the spring manufacturer, providing that a minimum as-
2.1 ASTM Standards:
quenched hardness of Rockwell HRC-50 will be achieved at
A29/A29M SpecificationforSteelBars,CarbonandAlloy,
the center of the bar section representing the spring when
Hot-Wrought and Cold-Finished, General Requirements
quenched in the same media and manner as the spring.
for
4.1.3 Springs Made from Bars Over 2 in. (50.8 mm)—Note
A689 Specification for Carbon and Alloy Steel Bars for
that the bias tolerance (reference Specification A29/A 29M,
Springs
Table A1.1 on Permissible Variations in Cross Section for
E10 Test Method for Brinell Hardness of Metallic Materi-
Hot-Wrought Round, Square, and Round-Cornered Square
als
Bars of Steel) of the bar diameter shall be taken into consid-
E112 Test Methods for Determining Average Grain Size
eration when designing and calculating the solid height, spring
E709 Guide for Magnetic Particle Examination
rate, solid stress, and solid capacity.
3. Ordering Information
4.2 Hardness:
4.2.1 The springs must be quenched and tempered to a
3.1 Orders for springs under this specification shall include
sufficiently high hardness (strength) to withstand the stresses
the following information:
developed in testing the finished spring. The maximum hard-
3.1.1 Quantity,
ness shall not exceed 477 Brinell numbers (2.80 mm indenta-
3.1.2 Name of material,
tion diameter).
4.2.2 When hardness limits are specified, the total range or
This specification is under the jurisdiction ofASTM CommitteeA01 on Steel,
spread may not be less than 0.15 mm difference in indentation
StainlessSteel,andRelatedAlloys andisthedirectresponsibilityofSubcommittee
diameters. The specified or indicated minimum hardness must
A01.15 on Bars.
be sufficient to develop the required strength to withstand the
Current edition approved Jan. 25, 1996. Published February 1996. Originally
published as A125–29T. Last previous edition A125–95. solid stresses of the spring design involved.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn. Contact ASTM
International (www.astm.org) for the latest information.
A 125 – 96 (2001)
TABLE 2 Brinell Hardness
4.2.3 Hardness shall be read on a prepared flat surface in an
area not detrimental to the life of the spring at a full section
Indentation Diameter, mm Brinell Hardness Numbers
after removal of the decarburized layer. A tungsten-carbide
2.75 495
10-mm ball shall be applied under a 3000-kg load and the
2.80 477
indentation diameter converted to Brinell numbers by using
2.85 461
2.90 444
Table 1. The values for Table 1 have been taken from
2.95 429
SpecificationE10.
3.00 415
4.3 Metallurgical Requirements:
3.05 401
3.10 388
4.3.1 The total depth of decarburization, partial plus com-
3.15 375
plete as measured on the finished spring in the quenched and
tempered condition, shall not exceed 0.006 in. (0.15 mm) plus
1%ofthebardiameter.Thedecarburizationshallbeexamined
at 1003 on a test specimen suitably etched and cut from a full
approximate contact with the adjacent coil and shall not
cross section of the test spring showing at least one lineal inch
protrude beyond the maximum permissible outside diameters
of original bar circumference.
of the spring as established by Table 2.
4.3.2 The structure of the finished spring shall have an
4.4.2 Springs with ground ends having a free height-to-
averageASTM Grain Size No. 5 or finer as determined by the
mean diameter ratio of not less than 1 or more than 5 shall not
latest revision of Test MethodsE112.
deviate from the perpendicular more than the number of
4.4 End Construction:
degrees prescribed in Table 3, as determined by standing the
4.4.1 End Construction-Tapered Squared and Ground—
spring on its end and measuring the angular deviation of a
The end bearing surfaces of the spring shall be ground to
straightedge along the outer helix from a perpendicular to the
produce a firm bearing. The end bearing surfaces shall have a
plate on which the spring is standing.
minimum bearing surface of two thirds of the mean coil
4.4.3 Theendsofspringsshallbeparallelwithinatolerance
circumference and a minimum width of two thirds of the
oftwicethatspecifiedforthesquarenessofendsasdetermined
hot-tapered surface of the bar. The tip ends of the bar shall be
by standing the spring on its end and measuring the maximum
in approximate contact with the adjacent coil, and shall not
angular deviation of the other end from a plane parellel to the
protrude beyond the maximum permissible outside diameters
plate on which the spring is standing.
of the spring as established by Table 2.
4.4.1.1 End Construction Coil Blunt Squared and Ground
5. Physical Requirements Physical Requirements
(Optional)—The end bearing surfaces of the spring shall be
5.1 Measurements:
ground to produce a firm bearing. The end bearing surfaces
shall have a minimum ground bearing surface of two thirds of 5.1.1 Solid Height—The solid height is the perpendicular
the mean coil circumference and a minimum width of two distance between the plates of the testing machine when the
thirds of the bar diameter. The tip ends of the bar shall be in spring is compressed solid with the load specified in 7.3. The
TABLE 1 Permissible Out-of-Squareness, Springs with Ground Ends
Total Travel, in. (mm) Mean Diameter, in. (mm)
2 (51) Over 2 Over 4 Over 6 Over 8 Over 10 Over 12 Over 14 Over 16 Over 18
and to 4 to 6 to 8 to 10 to 12 to 14 to 16 to 18 to 20
under (51 to (102 to (152 to (203 to (254 to (305 to (356 to (406 to (457 to
102), incl 152), incl 203), incl 254), incl 305), incl 356), incl 406), incl 457), incl 508), incl
Degree
1 1
2 (51) and under 1 ⁄4 1 ⁄4 1111 . . . .
3 1 1 1
Over 2 to 4 (51 to 102), incl 1 ⁄4 1 ⁄2 1 ⁄4 1 ⁄4 1 1 1 . . .
1 3 1 1 1
Over 4 to 6 (102 to 152), incl 2 ⁄4 1 ⁄4 1 ⁄2 1 ⁄4 1 ⁄4 1 1 . . .
1 1 3 1 1 1
Over 6 to 8 (152 to 203), incl 2 ⁄2 2 ⁄4 1 ⁄4 1 ⁄2 1 ⁄4 1 ⁄4 1 1 . .
3 1 1 1 1 1
Over 8 to 10 (203 to 254), incl 2 ⁄4 2 ⁄2 21 ⁄2 1 ⁄2 1 ⁄4 1 ⁄4 1 . .
3 1 3 1 1 1 1
Over 10 to 12 (254 to 305), incl 3 2 ⁄4 2 ⁄4 1 ⁄4 1 ⁄2 1 ⁄2 1 ⁄4 1 ⁄4 1 .
1 3 3 1 1 1 1
Over 12 to 14 (305 to 356), incl . . . 3 2 ⁄2 21 ⁄4 1 ⁄4 1 ⁄2 1 ⁄2 1 ⁄4 1 ⁄4
3 1 3 3 1 1
Over 14 to 16 (356 to 406), incl . . . . . . 2 ⁄4 2 ⁄4 22 1 ⁄4 1 ⁄4 1 ⁄2 1 ⁄2
1 1 3 3 1
Over 16 to 18 (406 to 457), incl . . . . . . 3 2 ⁄2 2 ⁄4 22 1 ⁄4 1 ⁄4 1 ⁄2
3 1 1 1 3
Over 18 to 20 (457 to 508), incl . . . . . . 3 2 ⁄4 2 ⁄2 2 ⁄4 2 ⁄4 22 1 ⁄4
3 1 1 3
Over 20 to 22 (508 to 559), incl . . . . . . . . . 3 2 ⁄4 2 ⁄4 2 ⁄4 22 1 ⁄4
1 1 3
Over 22 to 24 (559 to 610), incl . . . . . . . . . . . . 3 2 ⁄4 2 ⁄4 22 1 ⁄4
1 1 1 1
Over 24 to 26 (610 to 660), incl . . . . . . . . . . . . . . . 2 ⁄2 2 ⁄2 2 ⁄4 2 ⁄4 2
1 1 1 1
Over 26 to 28 (660 to 701), incl . . . . . . . . . . . . . . . 2 ⁄2 2 ⁄2 2 ⁄4 2 ⁄4 2
3 1 1 1
Over 28 to 30 (702 to 762), incl . . . . . . . . . . . . . . . 2 ⁄4 2 ⁄2 2 ⁄4 2 ⁄4 2
3 3 1 1
Over 30 to 32 (762 to 813), incl . . . . . . . . . . . . . . . 2 ⁄4 2 ⁄4 2 ⁄2 2 ⁄2 .
3 3 1 1
Over 32 to 34 (813 to 864), incl . . . . . . . . . . . . . . . 2 ⁄4 2 ⁄4 2 ⁄2 2 ⁄2 .
3 3 3
Over 34 to 38 (864 to 914), incl . . . . . . . . . . . . . . . 3 2 ⁄4 2 ⁄4 2 ⁄4 .
3 3
Over 36 to 38 (914 to 965), incl . . . . . . . . . . . . . . . . . . 3 2 ⁄4 2 ⁄4 .
Over 38 to 42 (965 to 1016), incl . . . . . . . . . . . . . . . . . . . . . 3 3 . . .
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn. Contact ASTM
International (www.astm.org) for the latest information.
A 125 – 96 (2001)
TABLE 3 Permissible Variations in Outside Diameter of Helix
(For springs with D/d ratio not exceeding 8)
NOTE 1— (for design information) These permissible variations, exclusives of manufacturing taper, should be used as a guide in the design of
concentrically-nested helical-spring units for free assembly. The diametrical clearance desired is ⁄16 in. (1.59 mm) less than the sum of the applicable
tolerances of the nested spring units, but in no case shoulds it be less than ⁄8 in. (3.17 mm).
NOTE 2—In cases where radical clearance on existing concentrically-nested helical-spring units will not accommodate these tolerances, the nominal
insidediametersshallbeadheredtoascloselyaspracticable,withplusvariationontheouterspringsandminusvariationontheinnerspringstoguarantee
free assembly. Drawings must show reference to the complete nested spring units.
NOTE 3— (For springs with D/d ratio not exceeding 8) For D/d ratio greater than 8, increase tolerance 50%.
Nominal Outside Diameter, in. Nominal Free Height or Length of Spring, in. (mm)
(mm)
Up to 10 (254) Over 10 to 18 Over 18 to 26 Over 26 to 34 Over 34 to 42 Over 42 to 60
incl, 6 (254 to 457), (457 to 661), (661 to 874), (874 to 1067), (1067 to 1524),
incl, 6 incl, 6 incl, 6 incl, 6 incl, 6
1 3 1 5 3
Up to 6 (152), incl ⁄16 (1.59) ⁄32 (2.38) ⁄8 (3.17) ⁄32 (3.97) ⁄16 (4.76) . . .
3 1 3 1 1
Over 6 to 8 (152 to 203), incl ⁄32 (2.38) ⁄8 (3.17) ⁄16 (4.76) ⁄4 (6.35) ⁄4 (6.35) . . .
1 3 1 1 1
Over 8 to 12 (203 to 305), incl ⁄8 (3.17) ⁄16 (4.76) ⁄4 (6.35) ⁄4 (6.35) ⁄4 (6.35) . . .
1 1 1 1 5
Over 12 to 16 (305 to 406), incl . . . ⁄4 (6.35) ⁄4 (6.35) ⁄4 (6.35) ⁄4 (6.35) ⁄16 (7.94)
5 5 5 3
Over 16 to 20 (406 to 508), incl . . . . . . ⁄16 (7.94) ⁄16 (7.94) ⁄16 (7.94) ⁄8 (9.53)
3 3 3 7
Over 20 to 24 (508 to 610), incl . . . . . . ⁄8 (9.53) ⁄8 (9.53) ⁄8 (9.53) ⁄16 (11.00)
7 7 7 1
Over 24 to 28 (610 to 701), incl . . . . . . ⁄16 ⁄16 ⁄16 ⁄2
1 1 1 1
Over 28 (701), incl . . . . . . ⁄2 ⁄2 ⁄2 ⁄2
TABLE 5 Permissible Variations in Free Height, Loaded Height
solid height thus measured may be less, but shall not exceed
and Permanent Set
thespecifiednominalsolidheightbymorethanthelimitsgiven
in Table 4.
Nominal Total Deviation Deviation Permanent
5.1.2 Free Height—The free height is the height of the Deflection, in. (mm) From From Set, max,
Nominal Free Nominal in. (mm)
spring after the load specified in 7.3 has been released, and is
Height, max, Loaded
determined by placing a straightedge across the top of the A
in. (mm), 6 Height,
max,
springandmeasuringtheperpendiculardistancefromtheplate
in. (mm), 6
on which the spring stands to the bottom of the straightedge at
5 4 3
Up to 3 (76.2), incl ⁄32 (3.97) ⁄32 (3.17) ⁄64 (1.19)
the approximate center of the spring. Tolerances are shown in
8 5 4
Over 3 to 4 (76.2 to 102), incl ⁄32 (6.35) ⁄32 (3.97) ⁄64 (1.59)
Table 5.
8 6 4
Over 4 to 5 (102 to 127), incl ⁄32 (6.35) ⁄32 (4.76) ⁄64 (1.59)
11 7 5
5.1.3 Loaded Height—The loaded height is the perpendicu-
Over 5 to 6 (127 to 152), incl ⁄32 (8.73) ⁄32 (5.56) ⁄64 (1.99)
11 8 5
Over 6 to 7 (152 to 179), incl ⁄32 (8.73) ⁄32 (6.35) ⁄64 (1.99)
lardistancebetweentheplatesofthetestingmachinewhenthe
14 9 6
Over 7 to 8 (179 to 203), incl ⁄32 (11.0) ⁄32 (7.14) ⁄64 (2.38)
specified working load has been applied in compression.
14 10 6
Over 8 to 9 (203 to 228), incl ⁄32 (11.0) ⁄32 (7.94) ⁄64 (2.38)
17 11 7
Tolerances are shown in Table 5. Over 9 to 10 (228 to 254), incl ⁄32 (13.49) ⁄32 (8.73) ⁄64 (2.78)
17 12 7
Over 10 to 11 (254 to 279), incl ⁄32 (13.49) ⁄32 (9.53) ⁄64 (2.78)
5.1.4 Permanent Set—After determining the free height as
20 13 8
Over 11 to 12 (279 to 305), incl ⁄32 (15.87) ⁄32 (10.32) ⁄64 (3.17)
specified in 5.1.2, the permanent set is the difference between
20 14 8
Over 12 to 13 (305 to 330), incl ⁄32 (15.87) ⁄32 (11.00) ⁄64 (3.17)
23 15 8
this free height and the height after the spring has been Over 13 to 14 (330 to 356), incl ⁄32 (18.25) ⁄32 (11.91) ⁄64 (3.17)
23 16 9
Over 14 to 15 (356 to 381), incl ⁄32 (18.25) ⁄32 (12.70) ⁄64 (3.57)
compressed solid three additional times under the test load
26 17 9
Over 15 to 16 (381 to 406), incl ⁄32 (20.64) ⁄32 (13.49) ⁄64 (3.57)
specified in 7.3, measured at the same point and in the same
26 18 10
Over 16 to 17 (406 to 431), incl ⁄32 (20.64) ⁄32 (14.28) ⁄36 (3.97)
29 19 10
Over 17 to 18 (431 to 457), incl ⁄32 (23.01) ⁄32 (15.08) ⁄64 (3.97)
manner. Tolerances are shown in Table 5.
29 20 11
Over 18 to 19 (457 to 483), incl ⁄32 (23.01) ⁄32 (15.87) ⁄64 (4.37)
5.1.5 Uniformity of Pitch—The pitch of the coils shall be
21 11
Over 19 to 20 (483 to 508), incl 1 (25.40) ⁄32 (16.67) ⁄64 (4.37)
sufficiently uniform so that when the spring is compressed 22 12
Over 20 to 21 (508 to 533), incl 1 (25.40) ⁄32 (17.46) ⁄64 (4.76)
3 23 12
Over 21 to 22 (533 to 559), incl 1 ⁄32 (27.78) ⁄32 (18.25) ⁄64 (4.76)
3 24 13
Over 22 to 23 (559 t
...