GOST flanges are the Russian and CIS system: size is given as DN, rating as PN, and the sealing face is described by an execution number rather than an ASME facing code. The tables are not interchangeable with ASME ones, which is why this page exists separately.
Work covers GOST 33259, 12820, 12821 and 12815 across DN 15 to 1500 and PN 10 to PN 160, with PN 250 and other special values confirmed against the exact table or drawing before quotation. CIS project drawings and Russian-language purchase specifications are accepted as the basis for the enquiry. We also make threaded high-pressure flanges for lens-ring joints to GOST 9399-81 and the order drawing, confirming scope and testing per RFQ. The standard covers nominal pressures of 20–100 MPa. We supply GOST 9399-81 flanges across the standard's full range, up to 100 MPa. GOST 9399-81 is not within the scope of the EAEU (EAC) certificate described below, so no EAC claim covers these flanges.
Material equivalence is the trap on these projects. GOST 09G2S against ASTM A350 LF2 is a review question, not an automatic substitution - chemistry, impact energy and certificate wording all have to be checked before either grade is offered. Documents matter as much as dimensions here: MTC 3.1, marking, dimensional report, packing list language, PMI or NDT, and third-party inspection where the contract requires it.
Product family: Flanges
GOST flange RFQs are checked against DN, PN, standard reference, material, facing, inspection and export document needs.
The EAEU certificate of conformity that names us as manufacturer of forged flanges lists, next to its ASTM and EN grades, the GOST grades Russian specifications use, as printed: сталь 20 (steel 20), 09Г2С (09G2S), 15Х5М, 12Х1МФ, 08Х18Н10Т, 12Х18Н10Т and 10Х17Н13М2Т. Among flange standards it names GOST 12820-80, 12821-80 and 12822-80, with GOST 33259-2015 as the standard applied voluntarily. That list is the scope of the certificate, not a test result: an order's steel is shown on its own EN 10204 3.1 or 3.2 certificate. 09G2S against ASTM A350 LF2 remains a review question, decided per project and per impact-test temperature.
EAC is not GOST. The certificate confirms conformity with the EAEU technical regulation TR CU 032/2013 for placing the flanges on that market; the flange's dimensions, facing and grade still come from GOST 33259 or the project drawing. Shanxi Baolongda Forging Co., Ltd. is the manufacturer named on it, the applicant is YURAL GROUP LLC, Moscow, and it is valid to 23.04.2027.
The certificate as issued: EAEU certificate of conformity No. ЕАЭС RU C-CN.АБ53.В.04310/22 (PDF)
| Scope and rating | |
|---|---|
| GOST scope | GOST RFQs are reviewed by DN, PN, flange execution/type, sealing face, material and document language. |
| Standards and materials | |
| Standards / drawings |
|
| Material grades |
|
| Geometry, tolerance and inspection | |
| Size and rating review | Typical project review covers DN 15 to 1500, PN 10 to PN 160, with PN 250 or special values confirmed from the exact table/drawing. |
| Inspection depth | MTC 3.1, marking, dimensional report, packing list language, PMI/NDT and third-party inspection if required. |
| Reviewed before quotation |
|
| Buying logic | |
| Best-fit RFQ | Best for Russia, CIS and Central Asia projects using GOST 33259, 12820, 12821 or project drawings. |
| Buyer application | Oil, gas, chemical, power and industrial pipeline projects in GOST-based procurement systems. |
Your standard, drawing revision and project specification govern.
Also known as
We confirm each step against your drawing or standard before we quote.
Material grade, heat number, certificate basis and substitution limits are checked against the GOST Flanges drawing or standard before procurement is released.
The forging route is selected around flange type, section thickness, bore allowance, hub or neck geometry and pressure-service requirements.
Heat treatment is planned with the required record package, mechanical testing basis and impact-test condition where low-temperature or alloy service applies.
Rough machining opens reference faces, bore, hub, neck or sealing-face stock needed to control allowance before final flange machining.
Final machining controls facing, bore, bolt pattern, groove, sealing surface and flange-table or drawing tolerances before dimensional inspection is issued.
Inspection covers dimensional report, MTC 3.1, PMI and required UT, MT or PT records before the release documents are matched to the purchase order.
Marking, packing and export documents are prepared by PO line item so the GOST Flanges shipment can clear customs and be identified at site receiving.
List document requirements in the first RFQ; they affect price and schedule.
Yes. We work to GOST 33259, 12820, 12821 and 12815; GOST 33259 replaced the older references, which still appear on legacy drawings, so we check which one your project revision actually binds instead of treating the wordings as interchangeable.
By an execution number rather than an ASME facing code, with size given as DN and rating as PN. State the execution together with DN, PN, flange type, material and document language.
Only after review, never as an automatic substitution. Chemistry, impact energy and certificate wording all have to be checked, and the decision is made per project and per impact-test temperature before either grade is offered.
No. It confirms conformity with TR CU 032/2013 for placing forged flanges on the EAEU market; dimensions, facing and grade still come from GOST 33259 or the project drawing. We are the manufacturer named on it, and the applicant is YURAL GROUP LLC, Moscow.
DN 15 to 1500 and PN 10 to PN 160, with PN 250 and other special values confirmed against the exact table or drawing before quotation. Threaded high-pressure flanges for lens-ring joints to GOST 9399-81 are a separate case: we supply those across the standard's full range, up to 100 MPa.
Email quote@bldforgedirect.com with standard, drawing, material, quantity and inspection requirements.