ASTM A27/A27M – Steel Standart
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- Au février 1, 2023
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Designation: ASTM A27/A27M − 10
1. Scope*
- This specification covers carbon steel castings for gen- eral applications that require up to 70 ksi (485 MPa) minimum tensile
NOTE 1—The grades covered by this specification represent materials that are suitable for assembly with other steel castings or wrought steel parts by fusion welding. It is not intended to imply that all these grades possess the same degree of weldability or that the same welding techniques can be used on all castings. It is the responsibility of the purchaser to establish for himself a suitable welding technique.
- Several grades and two classes of steel castings are covered, as indicated The grade and class desired shall be specified by the purchaser.
- Grade N-1—Chemical analysis
- Grade N-2—Heat-treated but not mechanically
- Grade U-60-30 [415-205]—Mechanically tested but not heat-treated.
1.2.4 Grades 60-30 [415-205], 65-35 [450-240], 70-36
[485-250], and 70-40 [485-275]—Heat-treated and mechani- cally tested.
1.2.5 Class 1 and Class 2 steel castings shall be specified in accordance with 9.2.
- The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the
- This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appro- priate safety and health practices and determine the applica- bility of regulatory limitations prior to use.
2. Referenced Documents
A370 Kontrol Methods and Definitions for Mechanical Testing of Steel Products
A732/A732M Specification for Castings, Investment, Car- bon and Low Alloy Steel for General Application, and Cobalt Alloy for High Strength at Elevated Temperatures A781/A781M Specification for Castings, Steel and Alloy,
Common Requirements, for General Industrial Use A957/A957M Specification for Investment Castings, Steel
and Alloy, Common Requirements, for General Industrial Use
3. General Conditions for Delivery
- Except for steel investment castings, material furnished to this specification shall conform to the requirements of Specification A781/A781M, including any supplementary re- quirements that are indicated in the purchase order. Failure to comply with the general requirements of Specification A781/ A781M constitutes nonconformance with the specification. In case of a conflict between the requirements of this specification and Specification A781/A781M, this specification shall pre-
- Steel investment castings furnished to this specification shall conform to the requirements of Specification A957/ A957M, including any supplementary requirements that are indicated in the purchase order. Failure to comply with the common requirements of Specification A957/A957M consti- tutes nonconformance with this specification. In case of con- flict between the requirements of this specification and Speci- fication A957/A957M, Specification A957/A957M shall
4. Ordering Information
- Orders for material under this specification should include the following information in proper
- Quantity
- Specification, grade (1.2), and class (9.2)
- Description of the casting by pattern number or drawing
- Options in the specification, and
- Supplementary requirements desired, including stan- dards of acceptance
TABLE 2 Tensile Requirements
Tensile Strength min |
Yield Point, min, |
Elongation in 2 in. |
Reduction of Area, |
|
ksi (MPa) |
ksi (MPa) |
(50 mm), min, %B |
min, % |
|
Grade U-60-30 (415-205) |
60 (415) | 30 (205) | 22 | 30 |
Grade 60-30 (415-205) |
60 (415) |
30 (205) |
24 |
35 |
Grade 65-35 (450-240) |
65 (450) |
35 (240) |
24 |
35 |
Grade 70-36 (485-250) | 70 (485) | 36 (250) | 22 |
30 |
Grade 70-40 (485-275)C |
70 (485) |
40 (275) |
22 |
30 |
5. Heat Treatment
5.1 All castings of Grades N-2, 60-30 [415-205], 65-35 [450-240], 70-36 [485-250], and 70-40 [485-275] shall be heat-treated by full annealing, normalizing, normalizing and tempering, or quenching and tempering. Unless otherwise specified in the inquiry, contract, or order, the castings may be heat-treated by any one or combination of these heat- treatments at the option of the manufacturer
5.1.1 Heat-treatment shall be performed after castings have been allowed to cool from the pouring temperature to below the transformation range.
5.2 Furnace temperatures for heat-treating shall be regulated by the use of pyrometers.
6. Chemical Composition
- The steel shall conform to the requirements as to chemical composition prescribed in Table 1. Product analysis tolerances shall conform to the Product Analysis Tolerances shown in Specification A781/A781M. When residual element chemical content is of interest to the purchaser, S54 may be
7. Tensile Properties
- Except for Grades N-1 and N-2, one tension kontrol shall be performed on each heat and the mechanical properties thus determined shall conform to the requirements specified in Table 2. The tension kontrol shall be performed in accordance with Kontrol Methods and Definitions A370.
- Kontrol bars shall be poured in special blocks similar to those shown in Fig. 1 of Specification A781/A781M and from the same heat as the casting
- Kontrol coupons may be cut from the heat-treated (if required) castings or cast integrally with the castings at the producer’s
- The kontrol bars for heat-treated castings shall be heat- treated in production furnaces to the same procedure as the castings they represent. When specified by the purchaser, the kontrol bars shall be heat-treated with the castings.
- Kontrol specimens shall be machined to the biçim and dimensions shown in Fig. 4 of Kontrol Methods and Definitions A370, with the ends machined to fit the grips on the tensile testing machine to be used. Suggested types of ends for standard round tension kontrol specimens are shown in Fig. 5 of Kontrol Methods and Definitions A370
- Kontrol specimens shall be machined to the biçim and dimensions shown in Fig. 4 of Kontrol Methods and Definitions A370, with the ends machined to fit the grips on the tensile testing machine to be used. Suggested types of ends for standard round tension kontrol specimens are shown in Fig. 5 of Kontrol Methods and Definitions A370
- Kontrol specimens shall be machined to the biçim and dimensions shown in Fig. 4 of Kontrol Methods and Definitions A370, with the ends machined to fit the grips on the tensile testing machine to be used. Suggested types of ends for standard round tension kontrol specimens are shown in Fig. 5 of Kontrol Methods and Definitions A370
-
2. Retests
- If the results of the mechanical tests for any heat, lot, or casting do not conform to the requirements specified, retests are permitted as outlined in Kontrol Methods and Definitions A370. At the manufacturer’s option, castings may be reheat- treated and retested. When castings are reheat-treated, they may not be reaustenitized more than 3 times without the approval of the purchaser. Testing after reheat treatment shall consist of the full number of specimens taken from locations complying with the specification or order.
TABLE 1 Chemical Requirements
Carbon,B max | Manganese,B max | Silicon, max | Sulfur, max | Phosphorus, max | |
Grade N-1 (J02500) | 0,25 | 0,75 | 0,80 | 0,035 | 0,035 |
Grade N-2 (J03500) | 0,35 | 0,60 | 0,80 | 0,035 | 0,035 |
Grade U-60-30 [415-205] (J02500) | 0,25 | 0,75 | 0,80 | 0,035 | 0,035 |
Grade 60-30 [415-205] (J03000) | 0,30 | 0,60 | 0,80 | 0,035 | 0,035 |
Grade 65-35 [450-240] (J03001) | 0,30 | 0,70 | 0,80 | 0,035 | 0,035 |
Grade 70-36 [485-250] (J03501) | 0,35 | 0,70 | 0,80 | 0,035 | 0,035 |
Grade 70-40 [485-275] (J02501) | 0,25 | 1,20 | 0,80 | 0,035 | 0,035 |
A Specify Class 1 or Class 2 in addition to grade designation (see 9.2).
B For each reduction of 0.01 % carbon below the maximum specified, an increase of 0.04 % manganese above the maximum specified will be permitted to a maximum of 1.40 % for Grade 70-40 [485-275] and 1.00 % for the other grades.
1. Rework and Retreatment
- All welds shall be inspected to the same quality stan- dards as were used to inspect the
- If postweld heat-treatment is required, Class 1 must be specified along with the grade, and the welds to be heat-treated must be defined. If postweld heat-treatment is not required, Class 2 must be specified along with the grade
1. Keywords
- castings; general application; steel
SUPPLEMENTARY REQUIREMENTS
A list of standardized supplementary requirements for use at the option of the purchaser is described in Specification A781/A781M. Those which are considered suitable for use with this specification are listed below by title only. Additional supplementary requirements suitable for use with this specification at the option of the purchaser are described below. One or more of the supplementary requirements indicated below may be included in the purchaser’s order or contract. When so included, a supplementary requirement shall have the same force as if it were in the body of the specification. Supplementary requirements details not fully described shall be agreed upon between the purchaser and the supplier, but shall not negate any of the requirements in the body of the specification.
S1. Magnetic Particle Examination S2. Radiographic Examination
S3. Liquid Penetrant Examination S4. Ultrasonic Examination
S6. Certification S8. Marking
S9. Charpy Impact Kontrol
S10. Hardness Kontrol
S12. Kontrol Report
S13. Unspecified Elements
S14. Tension Kontrol from Castings
S51. Permissible Variations in Dimensional Tolerances for Castings Made from Mounted Patterns
S51.1 Tolerances for commercial steel castings (S51.1.1) made from mounted patterns and the surfaces that are not to be machined shall be in accordance with Table S51.1. Metal match plate patterns and precise molding methods can produce closer tolerances than the values shown in Table S51.1. Complex casting designs may require different permissible variations than those listed in Table S51.1
TABLE S51.1 Normally Expected Deviation of Linear Casting
Dimensions from Design Dimensions
Blueprint Dimension, in. (mm) Tolerances, in. (mm)
|
S51.1.1 The term “commercial castings” does not cover
castings requiring special fixtures for gaging, or finishing
castings by grinding to special tolerance gages beyond the
düzgüsel requirements as listed in Table S51.1.
S52. Gate and Riser Projections for Castings Made from
Mounted Patterns
S52.1 Castings shall have gates and risers removed in such
a manner that no riser or gate stub projects or a depression is
made beyond or below the casting design contour in an amount
that would exceed the values given in Table S52.1.,
TABLE S52.1 Gate and Riser Projection Tolerances
Riser or Gate Maximum Dimension, in. (mm) Maximum Projection, in. (mm) Maximum Depression, in. (mm)
Up to 4 (100), incl 1⁄8 (3) 1⁄8 (3) |
Over 4 to 8 (100 to 200), incl 1⁄4 (6) 1⁄8 (3) |
Over 8 to 20 (200 to 500), incl 3⁄8 (10) 1⁄8 (3) |
Over 20 to 30 (500 to 750), incl 1⁄2 (13) 1⁄4 (6) |
Over 30 (750) 3⁄4 (19) 1⁄4 (6) |
S53. Weight Deviation for Castings Made from Mounted Patterns
S53.1 The allowable deviations from the average casting weight are shown in Table S53.1
TABLE S53.1 Allowable DeviationA from Average Casting Weight
Casting Weight, lb (kilo) Positive Deviation, % Negative Deviation, %
Up to 100 (45), incl 8.0 8.0
Over 100 to 500 (45 to 230), incl 6.5 5.0
Over 500 to 10 000 (230 to 4540), incl 5.0 3.0
Over 10 000 (4540) 3.0 2.5
A Deviations do not apply to mass as calculated from a design drawing.
S54. Chemical Analysis for Residual Elements
S54.1 The manufacturer shall determine the percentage of
elements specified as follows, using procedures specified in
Specification A781/A781M. The chemical analysis thus determined shall conform to the following requirements:
Copper, max, % 0.50
Nickel, max, % 0.50
Molybdenum, max, % 0.25
Chromium, max, % 0.50
S54.2 Total content of these residual elements, maximum percent 1.00.
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