Excel Sc a48

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Approved By: Metallurgical Engineer Date: December7, 2005

Excel Foundry and Machine, Inc.Excel Material Specifications Manual 4

1.0 Material: ASTM A48 - 94a Close Grain Gray Iron

2.0 Characteristics: Excellent castability, good machinability, good wear resistance, high damping capacity,excellent compressive strength, and good tensile strength. Poor ductility and impact strength.

3.0 Scope: Gray Iron bushings are typically used in bushings and retainers. This material is available in cast formonly. The material is ordered to a class. The class is a numerical value followed by a letter. The numerical valuecorresponds to tensile strength in ksi while the letter designation refers to the size of test bar from which tensile barsare to be pulled (dependant upon the thickness of the casting). Excel foundry and maching typically utilizes heavycastings. Therefore the C letter designation is chosen, corresponding to a test bar thickness of 2.0 inches (50.8mm).

4.0 Specification Numbers: The following table gives a cross reference of specification numbers which describeequivalent materials.

ASTM Number UNS Number Excel Number

A48 - 94a F12801 CL30, CL40,CL45,CL50

5.0 Chemical Composition: None given. The ASTM Specification subordinates chemical composition to tensilestrength. The following chemistries have been successfully utilized at Excel Foundry and Machine and are providedfor reference only.

FOR REFERENCE PURPOSES ONLY:

Chemistry for Iron Cast at Excel Foundry and Machine, Inc.

Class C Si Mn S Cu Cr Ni Ti Pb

3.30 2.10 0.90 0.70 0.90 0.70 0.70 0.05 0.0530C2.90 1.60 0.50 - 0.50 0.30 - - -

3.30 2.10 0.90 0.70 0.90 0.70 0.70 0.05 0.0540C2.90 1.60 0.50 - 0.50 0.30 - - -

3.30 2.10 0.90 0.70 0.90 0.70 0.70 0.05 0.0545C2.80 1.50 0.50 - 0.40 0.20 - - -

3.30 2.10 0.390 0.70 0.90 0.70 0.70 0.70 0.0550C2.80 1.50 0.50 - 0.40 0.20 - 0.30 -

6.0 Heat Treat Requirements: None. Typical Brinell Hardness as cast is 180-220 BHN for Class 40C and 200 to 240for class 45C, and class 50C.

7.0 Mechanical Properties: Tensile bars representing castings conforming to this specification shall meet therequirements for tensile strength described in the following table.

Class Tensile Strength Nominal Test Bar

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ksi [MPa] Diameter, in [mm]30C 30 [241] 2.0 [50.8]40C 40 [276] 2.0 [50.8] 45C 45 [310] 2.0 [50.8] 50C 50 [345] 2.0 [50.8]

7.1 Sampling: A lot shall consist of one of the following:7.1.1 All metal poured from a single heating in a batch type melting furnace7.1.2 All the metal from two or more batch type melting furnaces poured into a single ladle or a single casting7.1.3 All the metal poured from a continuous melting furnace for a given period of time between changes in charge,

processing conditions, or aim-for chemistry or 4 hours, whichever is shorter.

7.2 Cast Test Bars Test bars shall be separate castings poured from the same lot as the castings they represent.Test bars shall be 2.00 [50.8mm] inches in diameter at mid length, +/- 0.10” [.5mm], and at least 7 inches [175mm]long. Variation from these dimensions is allowed with agreement from Excel Foundry and Machine. The barsshall be cast in dried, baked, or chemically bonded molds made mainly of aggregate of siliceous sand withappropriate binders. The average grain size of the sand shall approximate that of the sand in which the castingsare poured. Molds for the test bars shall be approximately at room temperature when poured. More than one testbar may be cast in a single mold, but each bar in the mold shall be surrounded by a thickness of sand not less thanthe diameter of the bar.

7.2.1 Test bars that are intended to represent castings that are air cooled in the mold to less than 900 ° F (480°C),before shakeout, shall be cooled in their molds to a temperature less than 900°F (480°C). They then may becooled in still air to room temperature.

7.2.2 Test bars intended to represent castings that are hotter than 900°F (480°C) at shakeout shall be cooled perparagraph 7.2.1 prior to shakeout.

7.3 When castings are heat treated, stress relieved, or heated in any other way, the test bar shall receive the sametreatment.

7.4 Tension test specimens shall be machined to the shape illustrated in Figure 1 Test Specimen B or C of ASTM A48The test specimen will be concentric with the axis of the test bar.

7.5 Testing will be in accordance with ASTM Test Method E8. The elapsed time from the beginning of loading tofracture will not be less than 20 seconds. One tension test will be performed on each lot.

7.6 It the results of a valid test fails to conform with the specified requirements, two retests may be made. If eitherretest fails to meet specification requirements, the castings represented by the test coupons will be rejected.

7.7 If initial testing shows heat treatment is required to meet the mechanical property requirements, the entire lot ofcastings and representative test specimens shall be heat treated together. After heat treatment testing therepresentative samples shall be tested per 7.5 and 7.6.

8.0 Surface Integrity and Roughness: The surface of the casting shall be examined visually and shall be free ofadhering sand, scale, cracks, porosity, blowholes, shrinkage defects, and hot tears. Unacceptable surface

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discontinuities shall be removed and their removal verified by visual examination. Unacceptable visual surfacediscontinuities are shown in, but not limited to, Visual Method MSS-SP-55.

9.0 Quality/Dimensions: All castings shall be made in a workmanlike manner and shall conform to the dimensionson the drawings.

10.0 Additional Inspections: When specified by purchase order or drawing, additional inspections (mag particle,Xray, ultrasonic, dye penatrant, ect) may be required. Additional inspections shall be in accordance with ASTMA781/A781M and it’s supplemental requirements.

11.0 Weld Repair Weld repair is generally not permitted on gray iron castings.

12.0 Certification Requirements:

12.1 Certificate of Conformance: Required for all castings purchased.12.2 Chemical analysis and/or mechanical testing with the appropriate reports may be required by the Quality,

Engineering or Purchasing Departments, or by the customer.12.2.1 Chemical Analysis Report:: If stated as a requirement on the casting order, the Supplier shal

furnish a chemical analysis report for each heat of castings. If no chemical analysis report isrequired, the Supplier is required to maintain a certificate of analysis at the suppliers facility fora minimum of two years.

12.2.2 Mechanical Properties Report:: If stated as a requirement on the casting order, the Suppliershall furnish information regarding the mechanical properties for each heat of castings. If nomechanical analysis report is required, the Supplier is required to maintain a material test

report including mechanical properties for a minimum of two years.

13.0 Casting Identification: When possible, the drawing and/or casting order shall designate the type and location ofthe marking by the Supplier. Identification marking, as a minimum, shall include:

-Casting part number-Heat and/or serial number

14.0 Ordering Information: The following information, as a minimum, should be included on the casting order:-Part name-Part number-Quantity required-Required Class-Delivery schedule-Title, number and date of this standard-Test and inspection reports which are required for the particular order

REFERENCE SPECIFICATIONS

ASTM A48 Standard Specification for Steel Castings, High Strength, for Structural Purposes

ASTM E8 Test Methods for Tension Testing of Metallic Materials.

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Revision History

Revision

No.

Description of Changes and Pages Affected Date

Original Initial Release 12/07/2005

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Excel Sc a48