CCS FH620 (F620) Steel Plate – Properties & Equivalents

CCS FH620 (also written CCS F620, CCS/F620, CCS Grade F620 or FH620 steel plate) is a high-strength steel for welded marine and offshore structures certified by the China Classification Society (CCS) to CCS Rules for Materials and Welding (2024), Part 1, Chapter 3, Section 4 (High Strength Steels for Welded Structures). The number 620 is the minimum yield strength in MPa (up to 50 mm), tensile strength is 700–890 MPa, and the letter F sets the Charpy V-notch test temperature of −60°C. It is delivered thermo-mechanically rolled (TM) or quenched and tempered (QT) and corresponds to grade FH620 in IACS UR W16.

Gangsteel, a steel plate exporter, supplies CCS FH620 plate with CCS class certificates; the requirements below are taken directly from the current CCS rules.

Related CCS grades: CCS AH620 steel plate, CCS DH620 steel plate, CCS EH620 steel plate, CCS FH550 steel plate, CCS FH690 steel plate.

CCS FH620 chemical composition

CCS FH620 chemical composition, heat (ladle) analysis, % max unless stated, by delivery condition

Element	Heat analysis, TM	Heat analysis, QT
C	≤ 0.14	≤ 0.18
Mn	1.00–1.70	≤ 1.70
Si	≤ 0.60	≤ 0.80
P	≤ 0.020	≤ 0.020
S	≤ 0.010	≤ 0.010
Al (total)	≥ 0.02	≥ 0.018
Nb	≤ 0.05	≤ 0.06
V	≤ 0.12	≤ 0.12
Ti	≤ 0.05	≤ 0.05
Ni	≤ 2.00	≤ 2.00
Cu	≤ 0.55	≤ 0.50
Cr	≤ 0.50	≤ 1.50
Mo	≤ 0.50	≤ 0.70
N	≤ 0.025	≤ 0.015

 

Source: CCS Rules for Materials and Welding (2024), Part 1, Chapter 3, Table 3.4.3.2 (same values as IACS UR W16 Rev.3). Notes: Nb+V+Ti ≤ 0.26% and Mo+Cr ≤ 0.65% (not applicable to QT); total Al/N ≥ 2:1 unless other nitrogen-binding elements are used; Ni above 2.00% may be approved by CCS; boron, if added, ≤ 0.005%. CCS specifies the chemical composition as a heat (ladle) analysis only; the Rules give no product (check) analysis tolerances for these plates, so no product-analysis column is shown. If a product analysis is required, agree the tolerances in the order.

CCS FH620 mechanical properties and impact test

CCS FH620 tensile and Charpy V-notch requirements

Thickness (mm)	Yield ReH min (MPa)	Tensile Rm (MPa)
3 ≤ t ≤ 50	620	700–890
50 < t ≤ 100	580	700–890
100 < t ≤ 250	560	650–830

CCS FH620 elongation and impact energy

Elongation A5 min, T (%)	Elongation A5 min, L (%)	Charpy test temp.	KV avg min, T (J)	KV avg min, L (J)
15	17	−60°C	41	62

Source: CCS Rules for Materials and Welding (2024), Part 1, Chapter 3, Table 3.4.7.4. Plates over 600 mm wide are impact tested transversely (T value applies). For N/NR and TM plates one impact test is taken from each piece; for QT plates from each individually heat-treated piece. Above 50 mm, impact specimens are taken at t/4 and t/2.

CCS FH620 maximum carbon equivalent (plates)

Delivery condition	Ceq t ≤ 50 mm	Ceq 50 < t ≤ 100 mm	Ceq 100 < t ≤ 250 mm	CET	Pcm
TM	0.50	0.52	n/a	0.34	0.26
QT	0.56	0.60	0.64	0.38	0.30

Table 3.4.3.4. Ceq = C + Mn/6 + (Cr + Mo + V)/5 + (Ni + Cu)/15; CET = C + (Mn + Mo)/10 + (Cr + Cu)/20 + Ni/40 (H460 and above, at the mill’s option); Pcm may be used for TM and QT steels with C ≤ 0.12%. n/a = not applicable.

CCS FH620 thickness range and delivery condition

CCS FH620 maximum plate thickness by delivery condition

Delivery condition	Max plate thickness (mm)
TM	150
QT	150

Table 3.4.6.2. Thicker plates (N over 250 mm, QT over 150 mm) need special consideration by CCS. Yield and tensile requirements fall in steps above 50 mm and 100 mm, as shown in the table above.

CCS FH620 equivalent grades

CCS FH620 equivalent grades of other classification societies

Standard / society	Equivalent grade
IACS UR W16	FH620
ABS	AB/FQ63
DNV	VL F620
LR	LR FH62
ASTM A131	no equivalent (A131 stops at the 40 strength level)

The IACS member societies use the same unified requirements, so these grades match in chemistry and properties. A plate still needs the certificate of the vessel’s own class society; one plate can carry dual or multiple class certification only when each society’s surveyor witnesses the tests.

CCS FH620 FAQ

Is CCS F620 the same as CCS FH620?

Yes. CCS lists the grade as FH620; F620 is a common shorthand for the same steel.

What is the yield strength of CCS FH620?

Minimum 620 MPa up to 50 mm, 580 MPa for 50–100 mm and 560 MPa for 100–250 mm. Tensile strength is 700–890 MPa (up to 100 mm).

What is the impact test temperature of CCS FH620?

−60°C, with a minimum average of 41 J transverse or 62 J longitudinal.

What is CCS FH620 equivalent to?

FH620 in IACS UR W16, ABS AB/FQ63, DNV VL F620 and LR FH62. ASTM A131 has no grade at this strength.

How is CCS FH620 supplied?

TM (including TM with accelerated cooling or direct quenching and tempering) or QT. The chemistry and carbon-equivalent limits depend on the delivery condition.

What is the maximum thickness of CCS FH620 plate?

Up to 150 mm in TM or QT condition; thicker plates need special consideration by CCS.

What is the CEV of CCS FH620?

Ceq maximum for plates up to 50 mm is 0.50% (TM), 0.56% (QT). Higher limits apply to thicker plates.

What is the difference between CCS FH620 and the A, D, E and F grades of the same strength?

The strength requirements are identical; only the Charpy test temperature changes (0, −20, −40 or −60°C), and E/F grades have tighter P and S limits.

Equivalent steel grade of CCS/F620
DNV	GL	LR	BV	ABS	NK	KR	RINA
NV F620	GL-F620	LR/FH62	BV/F620	AB/FQ63	K F63	R F63	RI/F620

If you need more stock steel plates in shipbuilding steel plate, please click warehouse sizes.

Related steel grades: CCS/A620, CCS/D620, CCS/E620, CCS/F690

 

CCS Steel Plate Grade
General Strength	CCS/A	CCS/B	CCS/D	CCS/E
High Strength	CCS/A32	CCS/D32	CCS/E32	CCS/F32
	CCS/A36	CCS/D36	CCS/E36	CCS/F36
	CCS/A40	CCS/D40	CCS/E40	CCS/F40
Extra Strength	CCS/A420	CCS/D420	CCS/E420	CCS/F420
	CCS/A460	CCS/D460	CCS/E460	CCS/F460
	CCS/A500	CCS/D500	CCS/E500	CCS/F500
	CCS/A550	CCS/D550	CCS/E550	CCS/F550
	CCS/A620	CCS/D620	CCS/E620	CCS/F620
	CCS/A690	CCS/D690	CCS/E690	CCS/F690

 

LR equivalent: LR FH62 steel plate