Unknown steel

[KristjanGerhard]

Hi everyone,

Posting in the materials engineering section, let me know if this would be better placed somewhere else.

I am looking to identify steel used in a hydroelectric powerplant penstock and trifurcation. The plant is built in 1969 with the primary consultant being from the US.

According to drawings the penstock is made of "OX 520 G"
According to drawings the trifurcation is made of "Fb 50"

Is anyone familiar with these steel designations.

 

[TugboatEng]

Is it possible that FB indicates ferrite-bainite? Possibly this is a structure that requires high formability?

 

[LittleInch]

Any other information like size, wall thickness, design code used (if stated) or any other identifying marks or test results?

OX 520 is possibly a European grade with min tensile strength 520 MPa?

 

[DekDee]

As noted more info would be helpful.
FB 50 could possibly be Flat Bar 50 mm width but without more info - ???
OX 520 is shown on Google as being equivalent to S355 J2 so that may help.
What is the reason you are investigating ? Replacement, Repair ????

 

[KristjanGerhard]

Thanks for chipping in and taking interest.

Here is a snippet from one of the drawings, the OX 520 G designation is on line 2.1, the subscript is not quite clear. Might be upper case I or upper case L.
FB50 designation is on the following line.

The OX 520 G? designation is undoubtedly a material similar to S355 as the tensile strength is 570-610 MPa. Is anyone familiar with the reference standard?





The following drawing snippet shows the trifurcation and legs. The picture is taken with the back facing upstream the penstock into the trifurcation.




K.

 

[MintJulep]

with the primary consultant being from the US.

The drawing looks to be from Germany (or one of the other German speaking countries).

"OX" is possibly from "Oxelösund" which once might have been an independent mill, but is now part of SSAB. https://www.ssab.com/en/news/2023/06/ssab-invests-in-green-transformation-of-production-in-oxelsund

 

[LittleInch]

Nice picture

 

[KristjanGerhard]

The drawing looks to be from Germany (or one of the other German speaking countries).

"OX" is possibly from "Oxelösund" which once might have been an independent mill, but is now part of SSAB. https://www.ssab.com/en/news/2023/06/ssab-invests-in-green-transformation-of-production-in-oxelsund

Indeed. This drawing is from the Contractor (Krupp), the consulting engineer was nevertheless from the US. This does however sound quite likely. Thank you!

Nice picture

Thanks. We take every opportunity to 3D scan which also produces these images. Quite useful.

Regarding the FB50 designation there is a reference to Firebox steel from an American manufacturer in other documents but so far i have not been able to track down the steel mill.

 

[TugboatEng]

Do you have access to the special requirements for the steel so you can produce your own specification?