1、Standard Specification for Gray Iron Castings AASHTO Designation: M 105-09 (2013) American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001TS-4h M 105-1 AASHTO Standard Specification for Gray Iron Castings AASHTO Designation: M
2、 105-09 (2013) 1. SCOPE 1.1. This specification covers gray iron castings intended for general engineering use where tensile strength is a major consideration. Castings are classified on the basis of the tensile strength of the iron in cast test bars. 1.1.1. This specification subordinates chemical
3、composition to tensile strength. 1.2. Castings produced to this specification are graded on the basis of minimum tensile strength obtained in special test coupons designed to standardize cooling rate. The tensile strength developed in certain casting sections may vary from test coupon values. (See A
4、ppendix X1.2.) 1.3. The values stated in SI units are to be regarded as the standard. 1.4. AASHTO M 306 may be specified for drainage structure castings such as frames, grates, rings, and covers for inlets, manholes, and other structures if loading requirements exceed normal highway loading or if mo
5、re restrictive dimensional tolerances are required. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standard: M 306, Drainage, Sewer, Utility, and Related Castings 2.2. ASTM Standards: A644, Standard Terminology Relating to Iron Castings E8/E8M, Standard Test Methods for Tension Testing of Metallic Materials 2.
6、3. Military Standard: MIL-STD-129, Marking for Shipment and Storage12.4. Federal Standard: Fed. Std. No. 123, Marking for Shipment (Civil Agencies)13. TERMINOLOGY 3.1. Definitions of Terms Specific to This Standard: 3.1.1. manufacturera producing foundry/facility where iron is melted and poured into
7、 molds. 3.1.2. supplieran agent, representative, or organization that provides castings that it did not manufacture. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4h M 105-2 AASHTO 3.1.3. purchasert
8、he end user of the casting. 3.2. The preceding terms and definitions are specific to this specification. ASTM A644 contains other terms and definitions relating to gray iron castings. 4. CLASSIFICATION 4.1. Castings ordered and produced in accordance with this specification are classified into a num
9、ber of grades based on the properties of cast test bars (Table 1). Each class is designated by a number followed by a letter. The number indicates the minimum tensile strength of the cast test bar, and the letter indicates the size of the test bar. Examples of proper designations are as follows: Gra
10、y Iron Castings, M 105, Class 30B Gray Iron Castings, M 105, Class 40C 5. ORDERING INFORMATION 5.1. Orders for material to this specification shall include the following information: 5.1.1. AASHTO designation number and year of issue; 5.1.2. Class of iron required (Section 4.1 and Table 1); 5.1.3. T
11、he size of the cast test bar (letter classificationA, B, C, or S) that best represents the thickness of the controlling section of the casting (Table 3); 5.1.4. The tension test specimen (B or C) to be machined from test bar C (Section 11.3, Table 2, and Figure 2); 5.1.5. The tension test specimen t
12、o be machined from test bar S (Section 11.4, Table 2, and Figure 2); 5.1.6. Lot size (Section 14); 5.1.7. Special requirements (Section 7); 5.1.8. Saving tested specimens or unbroken test bars (Section 16.4); and 5.1.9. Special preparation for delivery (Section 18). 6. TENSILE REQUIREMENTS 6.1. Test
13、 bars representing castings conforming to this specification shall meet the requirements for tensile strength as described in Table 1. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4h M 105-3 AASHTO
14、 Table 1Requirements for Tensile Strength of Gray Cast Irons in Cast Test Bars Class Tensile Strength, Min, MPa ksi Nominal Test Bar, Dia, mm in. Class Tensile Strength, Min, MPa ksi Nominal Test Bar, Dia, mm in. No. 20A 138 20 22.4 0.88 No. 45A 310 45 22.4 0.88 No. 20B 30.5 1.2 No. 45B 30.5 1.2 No.
15、 20C 50.8 2.0 No. 45C 50.8 2.0 No. 20S Bar SaNo. 45S Bar SaNo. 25A 172 25 22.4 0.88 No. 50A 345 50 22.4 0.88 No. 25B 30.5 1.2 No. 50B 30.5 1.2 No. 25C 50.8 2.0 No. 50C 50.8 2.0 No. 25S Bar SaNo. 50S Bar SaNo. 30A 207 30 22.4 0.88 No. 55A 379 55 22.4 0.88 No. 30B 30.5 1.2 No. 55B 30.5 1.2 No. 30C 50.
16、8 2.0 No. 55C 50.8 2.0 No. 30S Bar SaNo. 55S Bar SaNo. 35A 241 35 22.4 0.88 No. 60A 414 60 22.4 0.88 No. 35B 30.5 1.2 No. 60B 30.5 1.2 No. 35C 50.8 2.0 No. 60C 50.8 2.0 No. 35S Bar SaNo. 60S Bar SaNo. 40A 276 40 22.4 0.88 No. 40B 30.5 1.2 No. 40C 50.8 2.0 No. 40S Bar SaaAll dimensions of test bar S
17、shall be as agreed upon between the manufacturer and the purchaser. 7. SPECIAL REQUIREMENTS 7.1. When agreed upon in writing between the manufacturer and the purchaser, it may be necessary for the castings to meet special requirements regarding hardness, chemical composition, microstructure, pressur
18、e tightness, radiographic soundness, dimensions, surface finish, etc. 8. DIMENSIONAL REQUIREMENTS 8.1. The castings shall conform to the dimensions or drawings furnished by the purchaser, or, if there are no drawings, to the dimensions predicted by the pattern equipment supplied by the purchaser. 9.
19、 WORKMANSHIP AND FINISH 9.1. The surface of the casting shall be free of adhering sand, scale, cracks, and hot tears, as determined by visual examination. 9.2. No repairing by plugging or welding of any kind shall be permitted unless written permission is granted by the purchaser. 2015 by the Americ
20、an Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4h M 105-4 AASHTO 10. CAST TEST BARS 10.1. Test bars shall be poured from the same lot as the castings they represent, and shall have dimensions as shown in Table 2. Allo
21、wance may be made for reasonable pattern draft within the tolerances shown in Table 2. Test bars A, B, and C are all standard test bars in the form of simple cylinders. Test bar S is special and is intended for use where the standard bars are not satisfactory. Table 2Diameters and Lengths of Cast Te
22、st Bars As-Cast Diameter, mm in. Length, mm in. Test Bar Nominal (Mid-Length) Min (Bottom) Max (Top) Min (Specified) Max (Recommended) A 22.4 0.88 21.6 0.85 24.4 0.96 125 5.0 150 6.0 B 30.5 1.20 29.0 1.14 33.5 1.32 150 6.0 230 9.0 C 50.8 2.00 48.3 1.90 53.3 2.10 175 7.0 255 10.0 SaaAll dimensions of
23、 test bar S shall be as agreed upon by the manufacturer and the purchaser. 10.2. The separately cast test bars shall be cast in dried, baked, or chemically bonded molds made mainly of an aggregate of siliceous sand with appropriate binders. The average grain size of the sand shall approximate that o
24、f the sand in which the castings are poured. Molds for the test bars shall be approximately at room temperature when poured. More than one test bar may be cast in a single mold, but each bar in the mold shall be surrounded by a thickness of sand that is not less than the diameter of the bar. A suita
25、ble design for a separately cast test bar mold is shown in Figure 1. Required Features Optional Features 1. MaterialAggregate of dry siliceous sand. 1. Number of test bars in a single moldTwo suggested. 2. PositionBars vertical. 2. Design of pouring cup. 3. LSee Table 3. 3. P50 mm (2 in.), suggested
26、. 4. DSee Table 3. 4. N8 mm (5/16in.) in diameter, suggested. 5. WNot less than diameter, D. 5. M = 1.5 N, suggested. Figure 1Suitable Design and Dimensions for Mold for Separately Cast Cylindrical Tension Test Bars for Gray Iron 2015 by the American Association of State Highway and Transportation O
27、fficials.All rights reserved. Duplication is a violation of applicable law.TS-4h M 105-5 AASHTO 10.3. Test bars that are intended to represent castings that are cooled in the mold to less than 480C (900F), before shakeout, shall be cooled in their molds to a temperature less than 480C (900F). Then t
28、hey may be cooled in still air to room temperature. 10.4. Test bars that are intended to represent castings that are hotter than 480C (900F) when shaken out of their molds shall be cooled as described in Section 10.3 or (by agreement between the manufacturer and the purchaser) may be shaken out of t
29、heir molds at approximately the same temperature as the castings they represent. 10.5. When castings are stress-relieved, annealed, or otherwise heat treated, test bars shall receive the same thermal treatment and shall be treated adjacent to the castings they represent. Note 1The intent of these pr
30、ovisions is as follows: to prohibit the casting of test bars in molds of metal, graphite, zircon, lightweight aggregates, or other materials that would affect significantly the tensile strength of the iron; to prohibit control of tensile strength of the test bars by manipulation of the grain size of
31、 the sand; and to prohibit the casting of test bars in molds preheated substantially above room temperature. Table 3Cast Test Bars for Use When a Specific Correlation Has Not Been Established between the Test Bar and the Casting Thickness of the Wall of the Controlling Section of the Casting, mm (in
32、.) Test Bar Under 6 (0.25) S 6 to 12 (0.25 to 0.50) A 13 to 25 (0.51 to 1.00) B 26 to 50 (1.01 to 2) C Over 50 (2) S 11. TENSION TEST SPECIMENS 11.1. For Test Bar Athe tension test specimen A, as shown in Figure 2, shall be machined concentric with the axis of the test bar. 2015 by the American Asso
33、ciation of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4h M 105-6 AASHTO Dimensions, mm (in.) Tension Test, Specimen A Tension Test, Specimen B Tension Test, Specimen C GLength of parallel, min 13 (0.50) 19 (0.75) 32 (1.25) DDiamete
34、r 12.7 0.25 19.1 0.4 31.7 0.050 (0.500 0.010) (0.750 0.015) (1.25 0.025) RRadius of fillet, min 25 (1) 25 (1) 50 (2) ALength of reduced section, min 32 (11/4) 38 (11/2) 57 (21/4) LOverall length, min 95 (33/4) 100 (4) 160 (63/8) CDia of end section, approx 22.2 (7/8) 31.8 (11/4) 47 (17/8) ELength of
35、 shoulder, min 6 (1/4) 6 (1/4) 8 (5/16) FDia of shoulder 16 0.5 25 0.5 36 0.5 (5/8 1/64) (5/16 1/64) (17/16 1/64) BLength of end section a a a aOptional to fit holders on testing machine. If threaded, root diameter shall not be less than dimension, F. Figure 2Tension Test Specimens 11.2. For Test Ba
36、r Bthe tension test specimen B, as shown in Figure 2, shall be machined concentric with the axis of the test bar. 11.3. For Test Bar Ctension test specimens B or C, as shown in Figure 2, shall be machined concentric with the axis of the test bar. Unless the size of the tension test specimen to be ma
37、chined from test bar C is specified in writing by the purchaser, the decision whether to use tension test specimen B or C shall be made by the manufacturer of the castings. 11.4. For Test Bar Sthe nature and dimensions of the tension test specimen shall be determined by agreement between the manufac
38、turer and the purchaser. 12. TENSION TEST 12.1. Tension test specimens shall fit the holders of the testing machine in such a way that the load shall be axial. 12.2. The elapsed time from the beginning of loading in the tension test to the instant of fracture shall be not less than 15 s for test spe
39、cimen A and not less than 20 s for specimens B and C. 13. NUMBER OF TESTS AND RETESTS 13.1. The tension test shall be conducted in accordance with ASTM E8/E8M. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable
40、 law.TS-4h M 105-7 AASHTO 13.2. One tension test shall be performed on each lot and shall conform to the tensile requirements specified. 13.3. If the results of a valid test fail to conform to the requirements of this specification, two retests shall be made. If either retest fails to meet the speci
41、fication requirements, the castings represented by these test specimens shall be rejected. A valid test is one wherein the specimen has been properly prepared and appears to be sound and on which the approved test procedure has been followed. 13.4. If sufficient cast test pieces are not available, t
42、he manufacturer shall have the option of removing a test specimen from a location of representative casting, as agreed upon between the manufacturer and purchaser. 13.5. If the first test results indicate that a heat treatment is needed to meet the test requirements, the entire lot of castings and t
43、he representative test specimens shall be heat treated together. Testing shall proceed in accordance with Sections 13.1 through 13.4. 13.6. If, after testing, a test specimen shows evidence of a defect, the results of the test may be invalidated and another test made on a specimen from the same lot.
44、 14. SAMPLING 14.1. A lot shall consist of one of the following: 14.1.1. All the metal poured from a single heating in a batch type melting furnace. 14.1.2. All the metal from two or more batch type melting furnaces poured into a single ladle or a single casting. 14.1.3. All the metal poured from a
45、continuous melting furnace for a given period of time between changes in charge, processing conditions, or aim-for chemistry, or 4 h, whichever is the shorter period. The purchaser may agree to extend the 4-h time period to 8 h if the manufacturer can demonstrate sufficient process control to warran
46、t such an extension. 14.1.4. One ladle of iron having a mass of more than 910 kg (2000 lb). 14.2. When an individual casting is poured from more than one ladle of iron, or when the iron for that casting is melted in more than one melting unit or from a different melt or a different type of charge in
47、 the same melting unit, or both, the iron from each melting unit, melt, or type of charge shall be considered a different lot. 14.3. When more than one lot of iron is used to pour a single casting, the iron in each lot must conform to this specification. 14.4. When an individual casting is poured wi
48、th iron melted in more than one melting unit or from more than one melt or type of charge in the same melting unit, and when the irons from the different sources are mixed together thoroughly in a ladle before the casting is poured, the mixed iron in that ladle may be considered a lot. 2015 by the A
49、merican Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4h M 105-8 AASHTO 15. INSPECTION 15.1. Unless otherwise specified in the contract or purchase order, the supplier/manufacturer shall be responsible for carrying out all the tests and inspections required by this specification, using purchaser appr
