What difference between P265GH and P355GH steel plate？ - Knowledge

P265GH and P355GH are European standard (EN 10028-2) weldable steel grades used for pressure vessels, boilers, and heat exchangers, offering good high-temperature strength, plasticity, and weldability; the main difference is strength, with P355GH having a higher minimum yield strength (around 355 MPa) than P265GH (around 265 MPa), making P355GH better for more demanding high-pressure, high-temperature applications like petrochemical equipment, while P265GH serves similar but slightly less severe roles, both excellent for safe, reliable operation in demanding industrial environments.

P265GH steel plate Chemical Composition

Grades	C max	Si max	Mn. max	P max	S max	N max	AL min	Cr max	Cu max	Mo max	Ni max	Nb max	Ti max	V max
P265GH	0.20	0.40	0.5-1.40	0.03	0.025	0.012	0.020	0.300	0.3	0.08	0.30	0.01	0.03	0.02

P355GH steel plate Chemical Composition

C	Si	Mn	P	S	Cr	Cu	Mo	Ni
0.25 max	0.10 – 0.35	0.60 – 1.40	0.030 max	0.030 max	0.25 max	0.30 max	0.10 max	0.30 max

P265GH Merchanical Propertites

Grade	Thickness (mm)	Yield Strength MPa(min)	Tensile Strength MPa	Elongation % (min)	Impact Energy ( KV J) (min)
Grade	Thickness (mm)	Yield Strength MPa(min)	Tensile Strength MPa	Elongation % (min)	-20℃	0℃	20℃
P265GH	≤ 16	265	410 to 530	23	27	34	40
	16＜t ≤40	255	410 to 530	23	27	34	40
	40＜t ≤60	245	410 to 530	23	27	34	40
	6＜t ≤100	215	410 to 530	23	27	34	40
	100＜t ≤150	200	400 to 530	23	27	34	40
	150＜t ≤250	185	390 to 530	23	27	34	40

P355GH Merchanical Propertites

Grade		P355GH Mechanical Property
Grade	Thickness	Yield	Tensilmie	Elongation	Impact Energy(KV J) min
P355GH	mm	Min Mpa	Mpa	Min %	-20°	0°	+20°
	≤ 16	355	510-650	20	27	34	40
	16> to ≤40	345	510-650	20	27	34	40
	40> to ≤60	335	510-650	20	27	34	40
	60> to ≤100	315	490-630	20	27	34	40
	100> to ≤150	295	480-630	20	27	34	40
	150> to ≤250	280	470-630	20	27	34	40

P265GH

Meaning: P (Pressure Vessel), 265 (MPa minimum yield strength), GH (High Temperature).

Properties: Good plasticity, toughness, cold bending, and welding properties, non-alloy steel with special high-temperature performance.

Applications: Boilers, pressure vessels, heat exchangers, generally suitable for elevated working temperatures.

P355GH

Meaning: P (Pressure Vessel), 355 (MPa minimum yield strength), GH (High Temperature).

Properties: Higher strength and toughness than P265GH, excellent heat/corrosion resistance, good forming, suitable for high-temp/pressure/corrosive environments.

Applications: Reactors, storage tanks, boilers, steam turbines in oil, gas, chemical, and power industries.