SAF™ 3007

SAF™ 3007 – ‘Less is more’ has never been truer

SAF™ 3007 (UNS S83072) is the latest addition to Alleima’s growing duplex family, a super-duplex stainless steel grade especially developed for subsea umbilicals. The new tube offers a safe, lighter, stronger and more efficient alternative to SAF™ 2507, the current industry standard. To date, Alleima has delivered more than 160 million meters (525 million feet) to all major fabricators and applications worldwide, equivalent to circling the globe three times. Due to the refined chemical composition, SAF™ 3007 not only cuts overall costs, but provides a lighter tube that streamlines the entire umbilical manufacturing process, making the statement of “Less is more” both true and relevant.

Comparison of chemical compositions (nominal), %

	C	Si	Mn	P	S	Cr	Ni	Mo	W	N
SAF™ 2507	≤0.030	≤0.08	≤1.2	≤0.030	≤0.015	25	7	4.0	-	0.30
SAF™ 3007	≤0.030	.02	1.0	≤0.030	≤0.030	30	7	1.0	3.4	0.40

Key benefits

SAF™ 3007 versus SAF™ 2507

Higher yield strength
Equal or better fatigue properties
Equal corrosion resistance
Easier welding, with thinner and lighter walls

Mechanical properties

Fatigue tests completed on the 15.16 x 1.23 size. Fully approved and compliant (>40 cycles as per the criteria). It broke away from the HAZ.

Yield Test

Size 15.16x1.23	Rp 0.2 Measured to ±σ	Rp 0.2 Min Level - 3σ	Increase % Yield Strength
REF: SAF™ 2507	758 ± 16	710	-
SAF™ 3007	850 ± 9	802	+13%

Size
25.57x1.26

REF: SAF™ 2507	738 ± 16	690	-
SAF™ 3007	822 ± 13	783	+13%

Size
34.40x4.50

REF: SAF™ 2507	718 ± 16	670	-
SAF™ 3007	815 ± 16	767	+15%

Burst test

Size 15.16 x 1.23: Tubes burst at an average of 1704 bar.Welded samples burst at 1741 bar.

Size 25.57 x 3.26: Tubes burst at an average of 2655 bar.
Welded samples burst at 2599 bar.

Size 34.4 x 4.5: Tubes burst at an average of 2979 bar.
No welded samples tested yet, timing, end of Feb, 2024.
The minimum requirement for each size is dependent on
wall thickness and is 2 times the design working pressure.

Corrosion and microstructure properties

All corrosion testing is G48A testing.
Tubes at 50°C & Welded samples at 40°C.
Size 15.16 x 1.23: passed, no pits
Size 25.57 x 3.26: passed, no pits
Size 34.40 x 4.50: passed, no pits
Microstructure. The tested ferrite-austenite ratio is within the range of 45 – 55 % ferrite.
The microstructure is good, all intermetallic and particles measured are well below 0.05%,
the minimum standard for sigma phase.
Chromium nitrides are at slightly higher, but at similar levels as seen in SAF™ 2507.

Hardness test on welds

The specification for SAF™ 2507, calls out for 238 – 318 for Vikers Hardness HV5.
For the ½-inch ID (12.70 mm), the results were 280 – 318.
For the ¾-inch ID (19.05 mm), the results were 270 – 310.
It must be noted, a higher hardness is expected for a stronger material.

Review and download the SAF™ 3007 data sheet here.