BS ISO 630‑4:2021 Structural steels Part 4: Technical delivery conditions for high yield strength quenched and tempered structural steel plates and wide flats

BS ISO 630‑4:2021 Structural steels Part 4: Technical delivery conditions for high yield strength quenched and tempered structural steel plates and wide flats.
6 Requirements
6.1 Steelmaking process
See ISO 630-1.
If a special steelmaking process has been specified, this shall be reported in the inspection document.
The steels shall contain sufficient amount of nitrogen-binding elements and have a fine-grain structure.
The steels specified in this specification shall be fully killed.
6.2 Delivery condition
The products covered by this document are delivered in the quenched and tempered condition. The delivery condition is indicated in the inspection document.
6.3 Chemical composition
6.3.1 Heat analysis
The chemical composition determined by heat analysis shall conform with the values specified in Table A.1 or Table B!.
6.3.2 Product analysis
The product analysis of grades S460Q, S500Q, S550Q, S620Q, S690Q, S890Q and S960Q shall comply with the values given in TableA.2.
The permitted deviations on analysis of grades SG46OQ, SG500Q, and SG700Q, relative to the values for heat analysis, are given in Table B.2.
6.3.3 Carbon equivalent value
The maximum carbon equivalent value (CEV) requirements for Annex A grades are given in Table A.3 and for Annex B grades in Table B.3.
6.4 Mechanical properties
6.4.1 Tensile properties
The tensile properties at room temperature shall comply with the values specified in Table A.4 or Table B.4.
6.4.2 Charpy V-notch impact properties
The impact properties of Charpy V-notch test pieces shall comply with the values specified in Table A.5 or Table B.5. The orientation of the specimens shall be longitudinal, unless a transverse orientation is agreed between the purchaser and manufacturer (see i.2 Iso 630-1 and the values in Table A.6).
6.5 Surface condition See ISO 630-1.
6.6 Internal soundness See ISO 630-1.
6.7 Dimensions, tolerances on dimensions and shape, mass
See ISO 630‑1.
7 Inspection
Specific inspection shall be required for all grades. Refer to ISO 630‑1.
8 Sampling – Frequency of testing
8.1 Verification
The verification of mechanical properties shall be by heat.
8.2 Test units
8.2.1 Annex A
The test unit shall contain products of the same form, grade, quality, delivery condition and thickness range as specified in Table A.4 for the yield strength and shall be by heat and:
— 60 tonnes or part thereof.
8.2.2 Annex B
The test unit shall be taken on each plate and wide flat as heat treated.
9 Test methods
See ISO 630‑1.
10 Marking
See ISO 630‑1.
BS ISO 630‑4 pdf download.