Difference between Q245R and Q370R steel plate

Jan 22, 2026 Zanechat vzkaz

Q245R and Q370R are Chinese (GB standard) boiler and pressure vessel steel plates, with the numbers indicating minimum yield strength (245 MPa for Q245R, 370 MPa for Q370R) and 'R' signifying they're for pressure vessels, differing mainly in strength and chemical composition, with Q370R offering higher strength for tougher conditions and Q245R prioritizing weldability/cost, used for tanks, heat exchangers, and industrial equipment.

Q245R Chemical composition of the Product analysis of grade

	C %							V %
Q245R	0.20	0.35	0.5-1.10	0.30	0.30	0.30	0.08	0.05
			P %	S %
	0.03	0.02	0.025	0.01	0.05

Q370R Chemical composition% of the Product analysis of grade

	C %							V %
Q370R	0.18	0.55	1.2-.1.7	0.3	0.3	0.3	0.08	0.05
			P %	S %
	0.03	0.02	0.025	0.010	0.015-0.05

Q245R Mechanical Property



Q245R	3-16	245Mpa	400-520 Mpa	25%	0	34J
	16-36	235 Mpa	400-520 Mpa	25%	0	34J
	36-60	225 Mpa	400-520 Mpa	25%	0	34J
	60-100	205 Mpa	390-510 Mpa	24%	0	34J
	100-150	185 Mpa	380-500 Mpa	24%	0	34J
	150-250	175 Mpa	370-490 Mpa	24%	0	34J

Q370R Mechanical Property



Q370R	10-16	370Mpa	530-630 Mpa	20%	-20	47J
	16-36	360 Mpa	530-630 Mpa	20%	-20	47J
	36-60	340 Mpa	520-620 Mpa	20%	-20	47J
	60-100	330 Mpa	510-610 Mpa	20%	-20	47J

Strength: Q370R is a higher-strength steel than Q245R; Q370R has a minimum yield strength of 370 MPa, while Q245R has 245 MPa.

Composition: Q370R contains more Manganese (Mn) and added Niobium (Nb) for improved strength and toughness, making it suitable for higher pressures and temperatures.

Applications: Both are used in boilers, pressure vessels, and heat exchangers, but Q370R handles more demanding designs, while Q245R offers better weldability and cost-effectiveness for less severe requirements.

Standards: They follow China's GB713 standard.