2024年5月21日发(作者：圣绮艳)
ICS 77.140.45
H 40
National standard of the People's Republic of China
GB/T 700-2006
Replace GB/T 700-1988
碳素结构钢
Carbon structural steels
(ISO 630:1995, Structural steels –
Plates, wide flats, bars, sections and profiles, NEQ)
Issue date: Nov 1, 2006 Implementation date: Feb 1, 2007
Issued by: General Administration of Quality Supervision, Inspection and Quarantine of the
People’s Republic of China
Standardization Administration of the People's Republic of China (SAC)
Foreword
This standard is not equivalent to ISO 630:1995 Structural Steels in the respect of consistency. The
main differences between the two standards are as follows:
- No grades are specified corresponding to the yield strength levels of 185N/mm
2
and
355N/mm
2
;
- Grades Q195 and Q215 are specified corresponding to levels 195N/mm
2
and 215N/mm
2
;
- The phosphorus contents of class A steels of Q235 and Q275 are decreased by 0.005%;
The thickness of Q235 class B steel is divided into two levels according to the deoxidization
method and the carbon content is 0.20% in both levels;
- Q235 class B steel of which the thickness is smaller than 25mm may not be subject to test
with the consent of the buyer if the supplier can ensure that the impact absorbed energy is up
to standard;
- The yield strength of Q275 steel of which the thickness is bigger than 80mm~100mm is
increased by 10N/mm
2
;
- Cold bending test is added;
- Detailed batching rules are specified according to the situation of China.
This standard replaces GB/T 700-1988 Carbon Structural Steels and has the following changes in
comparison with GB/T 700-1988:
- Semi-killed steel is cancelled in “deoxidization method”;
- Grades Q255 and Q275 in GB/T 700-1988 are cancelled;
- Grade E275 in ISO 630:1995 is newly added and changed to the new grade Q275;
- The lower limits of carbon and manganese contents of each grade are cancelled, and the upper
limit of manganese content is increased;
- The limit of silicon content of rimmed steel and killed steel is cancelled;
- silicon content is changed from 0.30% to 0.35% (except for Q195);
- The phosphorus and sulphur contents of grade Q195 are decreased respectively from 0.045%
and 0.050% to 0.035% and 0.040%;
- The regulation for the elongation after fracture of the thickness (or diameter) level of not
bigger than 16mm is cancelled;
- “The upper limit of the tensile strength of wide strip steel (including sheared steel plate) is not
used as a term of delivery” and “Q235 class B steel of which the thickness is smaller than
25mm may not be subject to test with the consent of the buyer if the supplier can ensure that
the impact absorbed energy is up to standard” are added in the footnotes of Table 2;
- The regulation for the nitrogen content in the steel is modified;
- The regulation for impact test is modified and the figure of the minimum impact absorbed
energy of the samples of which the thickness is 5mm-10mm is added;
- The basis of batching is changed from “the same furnace and kettle number” to “the same
furnace number” and the limitation for the furnace number of mixed batch is cancelled.
Annex A of this standard is normative.
This standard was proposed by China Iron and Steel Association.
This standard is under the jurisdiction of National Technical Committee for Steel Standardization.
This standard was drafted by China Metallurgical Information & Standardization Institute, Capital
Iron and Steel Company, Handan Iron & Steel Group and Benxi Iron & Steel Group Co., Ltd.
2024年5月21日发(作者：圣绮艳)
ICS 77.140.45
H 40
National standard of the People's Republic of China
GB/T 700-2006
Replace GB/T 700-1988
碳素结构钢
Carbon structural steels
(ISO 630:1995, Structural steels –
Plates, wide flats, bars, sections and profiles, NEQ)
Issue date: Nov 1, 2006 Implementation date: Feb 1, 2007
Issued by: General Administration of Quality Supervision, Inspection and Quarantine of the
People’s Republic of China
Standardization Administration of the People's Republic of China (SAC)
Foreword
This standard is not equivalent to ISO 630:1995 Structural Steels in the respect of consistency. The
main differences between the two standards are as follows:
- No grades are specified corresponding to the yield strength levels of 185N/mm
2
and
355N/mm
2
;
- Grades Q195 and Q215 are specified corresponding to levels 195N/mm
2
and 215N/mm
2
;
- The phosphorus contents of class A steels of Q235 and Q275 are decreased by 0.005%;
The thickness of Q235 class B steel is divided into two levels according to the deoxidization
method and the carbon content is 0.20% in both levels;
- Q235 class B steel of which the thickness is smaller than 25mm may not be subject to test
with the consent of the buyer if the supplier can ensure that the impact absorbed energy is up
to standard;
- The yield strength of Q275 steel of which the thickness is bigger than 80mm~100mm is
increased by 10N/mm
2
;
- Cold bending test is added;
- Detailed batching rules are specified according to the situation of China.
This standard replaces GB/T 700-1988 Carbon Structural Steels and has the following changes in
comparison with GB/T 700-1988:
- Semi-killed steel is cancelled in “deoxidization method”;
- Grades Q255 and Q275 in GB/T 700-1988 are cancelled;
- Grade E275 in ISO 630:1995 is newly added and changed to the new grade Q275;
- The lower limits of carbon and manganese contents of each grade are cancelled, and the upper
limit of manganese content is increased;
- The limit of silicon content of rimmed steel and killed steel is cancelled;
- silicon content is changed from 0.30% to 0.35% (except for Q195);
- The phosphorus and sulphur contents of grade Q195 are decreased respectively from 0.045%
and 0.050% to 0.035% and 0.040%;
- The regulation for the elongation after fracture of the thickness (or diameter) level of not
bigger than 16mm is cancelled;
- “The upper limit of the tensile strength of wide strip steel (including sheared steel plate) is not
used as a term of delivery” and “Q235 class B steel of which the thickness is smaller than
25mm may not be subject to test with the consent of the buyer if the supplier can ensure that
the impact absorbed energy is up to standard” are added in the footnotes of Table 2;
- The regulation for the nitrogen content in the steel is modified;
- The regulation for impact test is modified and the figure of the minimum impact absorbed
energy of the samples of which the thickness is 5mm-10mm is added;
- The basis of batching is changed from “the same furnace and kettle number” to “the same
furnace number” and the limitation for the furnace number of mixed batch is cancelled.
Annex A of this standard is normative.
This standard was proposed by China Iron and Steel Association.
This standard is under the jurisdiction of National Technical Committee for Steel Standardization.
This standard was drafted by China Metallurgical Information & Standardization Institute, Capital
Iron and Steel Company, Handan Iron & Steel Group and Benxi Iron & Steel Group Co., Ltd.