St3sp, 09G2S, 40Kh, 12Kh18N10T …. Issued by Rosstandart. 2 grades and 2 standards are documented so far; each grade links to a full data sheet and a graded cross-reference to the other systems.
GOST designations encode chemistry in Cyrillic element letters, and most of the confusion in using them comes from transliteration rather than from the system itself. Г (G) is manganese, С (S) silicon, Х (Kh) chromium, Н (N) nickel, М (M) molybdenum, Т (T) titanium, Ф (F) vanadium.
So 09Г2С — usually written 09G2S — is 0.09 % carbon, 2 % manganese, silicon-bearing: a weldable low-alloy structural steel comparable to S355. 40Х is 0.40 % carbon with chromium, close to 41Cr4. 12Х18Н10Т is 0.12 % carbon, 18 % chromium, 10 % nickel, titanium-stabilised — the stainless grade equivalent to 321.
St3 and the delivery-condition suffixes
The plain structural series runs St0 to St6, roughly by increasing strength. What matters as much as the number is the suffix: kp (кп) is rimmed steel, ps (пс) semi-killed, sp (сп) fully killed.
Killed steel is deoxidised and has more uniform properties; rimmed steel is cheaper and segregates. St3sp — killed — is the grade that behaves like S235JR. St3kp does not, and the difference will not be obvious from the number alone.
Using GOST material against an EN specification
GOST grades are frequently offered against EN enquiries in CIS and Central Asian markets, and many are genuinely suitable. The gaps to check are impact testing temperature, which GOST specifies differently, and the delivery condition suffix.
Where the project is code-governed or classed, a GOST certificate usually needs a conformity statement mapping the tested properties onto the EN requirement, rather than a bare equivalence table.
faq.h
What is 09G2S steel?
A GOST low-alloy weldable structural steel: 0.09 % carbon, about 2 % manganese, silicon-bearing. It is broadly comparable to S355 and is widely used in CIS markets for welded structures and pressure work.
What does St3sp mean?
St3 is a plain structural grade and sp (сп) means fully killed — deoxidised for uniform properties. St3sp is the variant that behaves like S235JR; St3kp is rimmed steel and does not.
How do I read Cyrillic element letters in GOST grades?
Г is manganese, С silicon, Х chromium, Н nickel, М molybdenum, Т titanium, Ф vanadium. The leading number is carbon in hundredths of a per cent, and numbers after a letter give that element's approximate percentage.
What is 12Kh18N10T equivalent to?
AISI 321 and EN 1.4541 — an 18/10 austenitic stainless stabilised with titanium to resist intergranular corrosion after welding.
Can GOST steel be used against an EN specification?
Often yes, but check impact test temperature and the delivery-condition suffix, which GOST handles differently. For code or class work, a conformity statement mapping the tested values onto the EN requirement is usually needed.