27SIMNA

GB/T 3077-2015 Table 1 gives ladle analysis; Table 2 gives P/S and residual-element requirements. The final note to Table 1 allows ordering any grade as higher or special quality by adding A or E after the grade; this record is higher-quality steel. For steel used in hot-pressure working, Cu ≤0.20%; the ordinary Cu maximum does not apply to this use. Explicit alloy ranges in Table 1 take priority; for Cr/Ni/Mo not specified there, use the residual limits in Table 2 and do not add residual limits on top of alloying-element ranges. Sn/Sb/As must be analyzed and recorded on the inspection certificate; any needed limits require agreement, and no generic numerical limits are invented here. Product-analysis deviations are handled separately under GB/T 222 and do not directly expand ladle limits. Mechanical properties depend on specimen dimensions and the recommended heat-treatment/delivery condition; this composition review does not constitute verification of properties.

Original 1999 edition heat analysis wt%; Save quality/high-quality A/extra-high-quality E and Table 2 phosphorus and sulfur residual requirements separately according to Table 1 Note 2. ; Clause 6.1.1.3: For hot-pressure working, Cu≤.20%.; If hot working is not specified, this restriction is not applied by default. ; 6.1.1.2 Residual W/V/Ti shall be analyzed and recorded in the quality certificate; specific limits are per requirement, and unspecified values shall not be filled as zero. ; Product processing methods shall be specified in the contract; Cold-heading suitability cannot be proven solely by alloy structural steel composition; delivery condition/hot upsetting/surface shall be verified separately. ; Finished product tolerances in Clause 6.1.2 shall be verified separately per GB222 and shall not expand the default heat analysis range.