Heavy Mechanical General Techniques and Standards - Part 6: Steel Castings
1 Scope
This part of JB/T 5000 specifies the technical requirements, test methods. inspection rules, marks and packing of the carbon and low alloy steel castings for heavy machinery.
This part is applicable to the carbon and low alloy steel castings cast in sand mould or the casting mould with equivalent thermal conductivity with the sand mould.
This part is not applicable to such special steel grades as high manganese steel, heat-resistant steel and stainless steel.
2 Normative References
The following normative documents contain provisions which, through reference in this part of JB/T 5000, constitute provisions of this part. For dated reference, subsequent amendments to, or revisions of, any of these publications do not apply. However, all parties coming to an agreement according to this part are encouraged to study whether the latest editions of these documents are applicable. For undated references, the latest edition of the normative document referred to applies.
GB/ T 222 Permissible Tolerances for Chemical Composition of Steel Products
GB/T 223 (all) Methods for Chemical Analysis of Iron, Steel and Alloy
GB/T 228 Tensile Test Methods on Metal (GB/T 228-2002, eqv ISO 6892: 1998)
GB/T 229 Metallic Materials - Charpy Notch Impact Test (GB/T 229-1994, eqv ISO 148: 1983)
GB/T 231.1 Metallic Materials - Brinell Hardness Test [GB/T 231.I- 2002, eqv ISO 6506-1: 1999 (E)]
NOTE 1: Each grade may be added with 0.04% of manganese when reducing per 0.01% of carbon, manganese of ZG 200-400 shall be 1.00% at most, that of the rest four grades shall be 1.20% at most.
NOTE 2: The gross amount of residual element shall not be larger than 1.00%. The residual elements may not be analyzed if not required by the buyer.
Table 2 Mechanical Property of Carbon Steel
Material grade Mechanical property≥
Yield point or yield strength
MPa Tensile strength MPa
Elongation
% Shrinkage factor
% Impact absorbing energy
J
J
ZG200-400 200 400 25 40 30 47
ZG230-450 230 450 22 32 25 35
ZG270-500 270 500 18 25 22 27
ZG310-570 310 570 15 21 15 24
ZG340-640 340 640 10 18 10 16
NOTE 1: The supplier may choose any one from and if not required by the buyer.
NOTE 2: The properties of each grade listed in the above table are applicable to the castings with thickness not larger than 100mm. And the yield strength specified in the table are only for design reference if the thickness of casting is larger than 100mm.
Foreword I 1 Scope 2 Normative References 3 Specifications 3.1 Grade, chemical composition and mechanical property 3.2 Surface quality 3.3 Repair welding 3.4 Dimensional tolerance 3.5 Finishing allowance 3.6 Weight deviation 3.7 Pattern draft 3.8 Tortuosity ratio 4 Test Methods and Test Rules 4.1 Chemical analysis 4.2 Mechanical test 4.3 Surface inspection 4.4 Dimension inspection 5 Marks and Packing 5.1 Marks and quality certificate 5.2 Painting and packing Figure 1 Dimensional Tolerance and Extreme Dimension Figure 2 Maximal Shifting Figure 3 Maximal Overall dimension of Finished Casting after Final Mechanical Processing Figure 4 Cast Steel Disc Figure 5 Single-cast Test Block for Mechanical Property Table 1 Chemical Composition of Carbon Steel Table 2 Mechanical Property of Carbon Steel Table 3 Chemical Composition of Low-alloy Steel Table 4 Mechanical Property of Low-alloy Steel Table 5 Roughness of Cast Surface Table 6 Cutting Surplus of Casting Head Table 7 Dimensional Tolerance Value of Casting Table 8 Finishing Allowance Table 9 Blank Dimension of Cast Steel Disc Table 10 Weight Deviation of Casting Table 11 Tortuosity Ratio of Casting
