GOST 33259 Flange Dimension Finder, Types 01 and 11

How to read the table

Row 1 (ряд 1) is the preferred one (clause 6.1 of the standard). Row 2 corresponds to ISO 7005-1; its connection dimensions D1, n and d are those of EN 1092-1 flanges. PN in GOST 33259 is stated in kgf/cm² (numerically about bar). Rows 1 and 2 have separate columns in Tables 3 and 6: their values may coincide or differ, so the order states the row.

• Facing A (flat face) is for PN 1, PN 2.5 and PN 6 only. Facing B is the raised face; type 11 takes it up to PN 100, and above that facings E, F and the others of Table 2.
• Row 2 has no facings E and F at PN 2.5 and PN 6 (Table 2, note 2).
• A dash (—) means the value is not shown because it is not confirmed by two sources; we do not fill it in. —¹ means the standard gives no value (the cell is blank or carries a dash). * means the customer sets the dimension (footnote to Tables 3 and 6).
• D1, n, d and the sealing-face dimensions are the mandatory connection dimensions (clause 7.6). The others may be refined by a strength calculation; since Change No. 1, b may not be less than the table value.

Thickness b runs to the sealing face

GOST 33259 measures the flange thickness b from the back of the flange to the sealing face. For facings B and F it therefore includes the raised-face height h, and for facing E the spigot height h1; for facing A, h = 0 and the table thickness is the whole thickness (Figure 3, note 2). Figures 4 and 7 of the standard draw b this way, and so do our model and drawing. The overall height H of type 11 runs to the same face. Without its raised face the flange is b − h thick.

ASME B16.5 and B16.47 state it the other way: their tf and Y exclude the raised face.

Sources and method

We checked each value against the text of the standard cell by cell, not row by row, using three kinds of source: the official text of GOST 33259-2015 (Standartinform edition, Tables 2, 3 and 6 read from the page images), independent electronic transcriptions of that text, and manufacturers' published tables. Corrigenda IUS 11-2016 and IUS 8-2017 and Change No. 1 (IUS 5-2024, in force from 1 June 2024) are applied, as are corrigenda IUS 10-2024 and IUS 3-2025, which change no dimension. A value is shown only where at least two independent sources agree and one of them is the official text. For row 2, the EN 1092-1 tables may serve as the second source, but only where their value equals the official text.

Change No. 1 added PN 40 to type 01 (DN 10 to 50, row 2 only). For now only the amendment itself lists those rows, with no second source, so we do not show their values.

What this finder does not cover

• Blind flanges: they are made to GOST 34785-2021, not GOST 33259. A blind-flange finder is planned.
• Types 02, 03 and 04 (loose flanges) and 21 (valve body flanges), and cast-iron flanges.
• Facings C, D, J, K, L and M.

What to send with an RFQ for a GOST 33259 flange

Clause 7.18 of the standard lists what the buyer states in a request and an order:

• DN and PN.
• Flange type: 01, 11 or another.
• Row: 1 or 2.
• Facing.
• Steel grade.
• Control group, per Table 13.
• For type 01, the pipe bore dв.
• For control groups IV and V, the pipe outside diameter and wall thickness.

Add the quantity, the inspection certificate you need and the destination port. The standard's own example designation reads «Фланец 150-10-01-1-B-Ст 20-IV-dв 161 ГОСТ 33259-2015»: DN 150, PN 10, type 01, row 1, facing B, steel 20, control group IV, pipe bore 161 mm.

The tables show what the standard lists, not what we make: send us your line items and we confirm them.

See also our GOST flanges page and the guide to GOST vs ASME flanges.

Reference only. This page is a buying aid, not the standard, and not a quotation. Manufacture, tolerances and acceptance go by the edition of GOST 33259 your order calls for and your drawing. Data checked 2026-10-15 · types 01 and 11 · PN 1 to 250 · rows 1 and 2.