EN 1092-1 · Standard reference
EN 1092-1 flange tolerances (Table 22)
Clause 5.9 of EN 1092-1:2018 refers all flange and collar dimensional tolerances to Table 22, and sends any dimension without a stated tolerance to the general tolerances of EN 22768-1:1993. Table 22 runs across six pages (77 to 82) and is reproduced here in full.
The table is organised the way the dimensions are: neck and bore first, then wall thickness and weld bevel, outside diameter, hub length, neck diameters, collar and flange thickness, facing geometry, and finally eccentricity and parallelism. Many tolerances depend on the flange type group and on whether a surface is machined, so read the flange-type cell together with the size band before taking the tolerance.
Tolerances in Table 22 are given as an upper and lower limit, as plus-only limits for bores and holes, or as a percentage of the outside diameter or wall thickness. Dimensions for which Table 22 states no tolerance fall back to EN 22768-1:1993.
- Standard
- EN 1092-1:2018
- Source table
- Table 22 (pp. 77–82)
- Clause
- §5.9 (p. 18)
- Units
- mm, %, degrees
- General tolerances
- EN 22768-1:1993
Neck outside diameter, bore, wall thickness and bevel (p. 77)
Wall thickness S has two tolerance regimes: a neck machined on both faces, and a neck machined on one face only or left unmachined.
EN 1092-1 · EN 1092-1:2018
| Dimension | Flange types | Size | Tolerance mm | Neck one face machined, or un-machined mm |
|---|---|---|---|---|
| Outside diameter of neck A | 11, 21, 34 | ≤ DN 125 | +3,0 / 0 | — |
| Outside diameter of neck A | 11, 21, 34 | > DN 125 ≤ DN 1200 | +4,5 / 0 | — |
| Outside diameter of neck A | 11, 21, 34 | > DN 1200 | +6,0 / 0 | — |
| Outside diameter of neck A | 35, 36, 37 | ≤ DN 150 | ±0,75 % a, min. ±0,3 mm | — |
| Outside diameter of neck A | 35, 36, 37 | > DN 150 | ±1 % a, max. ±3,0 mm | — |
| Bore diameter B1, B2, B3 | 01, 02, 04, 12, 32 | ≤ DN 100 | +0,5 / 0 | — |
| Bore diameter B1, B2, B3 | 01, 02, 04, 12, 32 | > DN 100 ≤ DN 400 | +1,0 / 0 | — |
| Bore diameter B1, B2, B3 | 01, 02, 04, 12, 32 | > DN 400 ≤ DN 600 | +1,5 / 0 | — |
| Bore diameter B1, B2, B3 | 01, 02, 04, 12, 32 | > DN 600 | +3,0 / 0 | — |
| Wall thickness S c | 11, 34 b | ≤ DN 100 | +1,0 / 0 | +2,0 / 0 |
| Wall thickness S c | 11, 34 b | > DN 100 ≤ DN 400 | +1,5 / 0 | +2,5 / 0 |
| Wall thickness S c | 11, 34 b | > DN 400 | +2,0 / 0 | +3,5 / 0 |
| Wall thickness S c | 35 | S ≤ 8 | +15 % / −10 % | — |
| Wall thickness S c | 35 | S > 8 | +15 % / −5 % | — |
| Wall thickness S c | 36, 37 | ≤ DN 600 | −12,5 % a / +15 % | — |
| Wall thickness S c | 36, 37 | > DN 600 | −0,5 mm a / +15 % | — |
| Bevelled wall thickness Sp | 35, 36, 37 | S ≤ 6 | +1,0 / 0 | — |
| Bevelled wall thickness Sp | 35, 36, 37 | S > 6 | +2,0 / 0 | — |
- a Tolerance in % of the outside diameter or of the wall thickness, as applicable.
- b Bore tolerance not applicable.
- c Preparation of ends, see Annex A.
Tolerance is given as upper / lower limit in mm unless a percentage is shown. Dimension letters follow the standard's dimension symbols. Wall thickness S has two regimes: a neck machined on both faces, and a neck machined on one face only or unmachined; the second value is in the right-hand column.
Outside diameter D, hub length and neck diameter N1 (p. 78)
EN 1092-1 · EN 1092-1:2018
| Dimension | Flange types | Size | Tolerance mm |
|---|---|---|---|
| Outside diameter D | 21 | ≤ DN 250 | ±4,0 |
| Outside diameter D | 21 | > DN 250 ≤ DN 500 | ±5,0 |
| Outside diameter D | 21 | > DN 500 ≤ DN 800 | ±6,0 |
| Outside diameter D | 21 | > DN 800 ≤ DN 1200 | ±7,0 |
| Outside diameter D | 21 | > DN 1200 ≤ DN 1600 | ±8,0 |
| Outside diameter D | 21 | > DN 1600 ≤ DN 2000 | ±10,0 |
| Outside diameter D | All other types | ≤ DN 150 | ±2,0 |
| Outside diameter D | All other types | > DN 150 ≤ DN 500 | ±3,0 |
| Outside diameter D | All other types | > DN 500 ≤ DN 1200 | ±5,0 |
| Outside diameter D | All other types | > DN 1200 ≤ DN 1800 | ±7,0 |
| Outside diameter D | All other types | > DN 1800 | ±10,0 |
| Length through hub H1, H2, H3, H4, H5 | 11, 12, 13, 34, 35, 36, 37 | ≤ DN 80 | ±1,5 |
| Length through hub H1, H2, H3, H4, H5 | 11, 12, 13, 34, 35, 36, 37 | > DN 80 ≤ DN 250 | ±2,0 |
| Length through hub H1, H2, H3, H4, H5 | 11, 12, 13, 34, 35, 36, 37 | > DN 250 | ±3,0 |
| Neck diameter N1 | 11 (machined bearing surface) | N1 ≤ 120 | 0 / −1,0 |
| Neck diameter N1 | 11 (machined bearing surface) | N1 > 120 ≤ 400 | 0 / −1,2 |
| Neck diameter N1 | 11 (machined bearing surface) | N1 > 400 ≤ 1000 | +1,6 / 0 |
| Neck diameter N1 | 11 (machined bearing surface) | N1 > 1000 ≤ 2000 | +2,5 / 0 |
| Neck diameter N1 | 11 (machined bearing surface) | N1 > 2000 | +4,0 / 0 |
| Neck diameter N1 | 11 (un-machined bearing surface) | N1 ≤ 120 | 0 / −1,0 |
| Neck diameter N1 | 11 (un-machined bearing surface) | N1 > 120 ≤ 400 | 0 / −2,0 |
| Neck diameter N1 | 11 (un-machined bearing surface) | N1 > 400 ≤ 1000 | +4,0 / 0 |
| Neck diameter N1 | 11 (un-machined bearing surface) | N1 > 1000 ≤ 2000 | +6,0 / 0 |
| Neck diameter N1 | 11 (un-machined bearing surface) | N1 > 2000 | +8,0 / 0 |
Tolerance is given as upper / lower limit in mm. Neck diameter N1 is toleranced differently depending on whether the bolting bearing surface is machined.
Neck diameters N1, N2 and N3 (p. 79)
EN 1092-1 · EN 1092-1:2018
| Dimension | Flange types | Size | Tolerance mm |
|---|---|---|---|
| Neck diameter N1, N2, N3 | 21, 34 (un-machined bearing surface) | ≤ DN 50 | 0 / −2,0 |
| Neck diameter N1, N2, N3 | 21, 34 (un-machined bearing surface) | > DN 50 ≤ DN 150 | 0 / −4,0 |
| Neck diameter N1, N2, N3 | 21, 34 (un-machined bearing surface) | > DN 150 ≤ DN 300 | 0 / −6,0 |
| Neck diameter N1, N2, N3 | 21, 34 (un-machined bearing surface) | > DN 300 ≤ DN 600 | 0 / −8,0 |
| Neck diameter N1, N2, N3 | 21, 34 (un-machined bearing surface) | > DN 600 ≤ DN 4000 | 0 / −10,0 |
| Neck diameter N1, N2, N3 | 21, 34 (machined bearing surface) | ≤ DN 50 | +1,0 / 0 |
| Neck diameter N1, N2, N3 | 21, 34 (machined bearing surface) | > DN 50 ≤ DN 150 | +1,5 / 0 |
| Neck diameter N1, N2, N3 | 21, 34 (machined bearing surface) | > DN 150 ≤ DN 300 | +2,0 / 0 |
| Neck diameter N1, N2, N3 | 21, 34 (machined bearing surface) | > DN 300 ≤ DN 600 | +2,5 / 0 |
| Neck diameter N1, N2, N3 | 21, 34 (machined bearing surface) | > DN 600 ≤ DN 4000 | +3,0 / 0 |
| Neck diameter N2, N3 | 12, 13 | ≤ DN 50 | +1,0 / 0 |
| Neck diameter N2, N3 | 12, 13 | > DN 50 ≤ DN 150 | +2,0 / 0 |
| Neck diameter N2, N3 | 12, 13 | > DN 150 ≤ DN 300 | +4,0 / 0 |
| Neck diameter N2, N3 | 12, 13 | > DN 300 ≤ DN 600 | +8,0 / 0 |
| Neck diameter N2, N3 | 12, 13 | > DN 600 ≤ DN 1200 | +12,0 / 0 |
| Neck diameter N2, N3 | 12, 13 | > DN 1200 ≤ DN 1800 | +16,0 / 0 |
| Neck diameter N2, N3 | 12, 13 | > DN 1800 | +20,0 / 0 |
Tolerance is given as upper / lower limit in mm.
Collar thickness, flange thickness and facing diameter (p. 80)
EN 1092-1 · EN 1092-1:2018
| Dimension | Flange types | Size | Tolerance mm |
|---|---|---|---|
| Collar thickness F | 35 (machined on both facings) | ≤ 18 mm thickness | ±1,0 |
| Collar thickness F | 35 (machined on both facings) | > 18 mm ≤ 50 mm thickness | ±1,5 |
| Collar thickness F | 35 (machined on front face only, or un-machined) | ≤ 18 mm thickness | +2,0 / −1,3 |
| Collar thickness F | 35 (machined on front face only, or un-machined) | > 18 mm ≤ 50 mm thickness | +4,0 / −1,5 |
| Collar thickness F | 36 (machined on front face only, or un-machined) | ≤ 18 mm thickness | ±10 % |
| Collar thickness F | 37 (un-machined) | ≤ 5 mm thickness | ±0,20 |
| Collar thickness F | 37 (un-machined) | > 5 mm thickness | ±0,30 |
| Collar thickness F | 32, 34 (machined on both faces) | ≤ 18 mm thickness | +1,0 / −1,3 |
| Collar thickness F | 32, 34 (machined on both faces) | > 18 mm thickness | ±1,5 |
| Collar thickness F | 32, 34 (machined on front side only) | ≤ 18 mm thickness | +2,0 / −1,3 |
| Collar thickness F | 32, 34 (machined on front side only) | > 18 mm ≤ 30 mm thickness | +3,0 / −1,5 |
| Collar thickness F | 32, 34 (machined on front side only) | > 30 mm thickness | +4,0 / −1,5 |
| Flange thickness C1, C2, C3, C4 | All types (machined on both faces) | ≤ 18 mm thickness | +1,0 / −1,3 |
| Flange thickness C1, C2, C3, C4 | All types (machined on both faces) | > 18 mm ≤ 50 mm thickness | ±1,5 |
| Flange thickness C1, C2, C3, C4 | All types (machined on both faces) | > 50 mm thickness | ±2,0 |
| Flange thickness C1, C2, C3, C4 | All types (machined on front side only); Type 02 and 04 (un-machined) | ≤ 18 mm thickness | +2,0 / −1,3 |
| Flange thickness C1, C2, C3, C4 | All types (machined on front side only); Type 02 and 04 (un-machined) | > 18 mm ≤ 50 mm thickness | +4,0 / −1,5 |
| Flange thickness C1, C2, C3, C4 | All types (machined on front side only); Type 02 and 04 (un-machined) | > 50 mm thickness | +7,0 / −2,0 |
| Facing diameter d1 | All types | ≤ DN 250 | +2,0 / −1,0 |
| Facing diameter d1 | All types | > DN 250 | +3,0 / −1,0 |
Tolerance is given as upper / lower limit in mm unless a percentage is shown.
Facing heights, facing dimensions and bolting (p. 81)
EN 1092-1 · EN 1092-1:2018
| Dimension | Flange types | Size | Tolerance mm |
|---|---|---|---|
| Facing height f1 | All types (facing type B, D, F and G) | ≤ DN 32 (2 mm) | 0 / −1,0 |
| Facing height f1 | All types (facing type B, D, F and G) | > DN 32 to DN 250 (3 mm) | 0 / −2,0 |
| Facing height f1 | All types (facing type B, D, F and G) | > DN 250 to DN 500 (4 mm) | 0 / −3,0 |
| Facing height f1 | All types (facing type B, D, F and G) | > DN 500 (5 mm) | 0 / −4,0 |
| Facing height f2 | All types (facing type C, E and G) | All DN | +0,5 / 0 |
| Facing height f3 | All types (facing type D and F) | All DN | +0,5 / 0 |
| Facing height f3 | All types (facing type H) | All DN | +0,2 / 0 |
| Facing height f4 | All types (facing type H) | All DN | +0,5 / 0 |
| Facing dimension W | All types | All DN | +0,5 / 0 |
| Facing dimension X | All types | All DN | 0 / −0,5 |
| Facing dimension Y | All types | All DN | +0,5 / 0 |
| Facing dimension Z | All types | All DN | 0 / −0,5 |
| Diameter of bolt circle K | All types | Bolt size M10 to M24 | ±1,0 |
| Diameter of bolt circle K | All types | Bolt size M27 to M45 | ±1,5 |
| Diameter of bolt circle K | All types | Bolt size > M45 | ±2,0 |
| Diameter of bolt holes L | All types | Bolt size M10 to M24 | +1,0 / 0 |
| Diameter of bolt holes L | All types | Bolt size M27 to M45 | +2,5 / 0 |
| Diameter of bolt holes L | All types | Bolt size > M45 | +4,0 / 0 |
| Centre-to-centre of adjacent bolt holes | All types | Bolt size M10 to M24 | ±1,0 |
| Centre-to-centre of adjacent bolt holes | All types | Bolt size M27 to M45 | ±1,5 |
| Centre-to-centre of adjacent bolt holes | All types | Bolt size > M45 | ±2,0 |
Tolerance is given as upper / lower limit in mm. Facing heights f1 to f4 correspond to the facing dimensions in Figure 4; W, X, Y and Z are facing dimensions of the tongue, groove, spigot and recess types.
Eccentricity and parallelism (p. 82)
EN 1092-1 · EN 1092-1:2018
| Dimension | Flange types | Size | Tolerance mm |
|---|---|---|---|
| Eccentricity of machined facing diameters d | All types | ≤ DN 65 | 1,0 |
| Eccentricity of machined facing diameters d | All types | > DN 65 | 2,0 |
| Parallelism between bolting bearing surface and flange jointing faces | All types (machined bearing surface) | All DN | 1° |
| Parallelism between bolting bearing surface and flange jointing faces | All types (un-machined bearing surface) | All DN | 2° |
- d Between bolt circle and facing, and also between bore diameter and facing.
Eccentricity is a maximum in mm; parallelism is an angle. Footnote d applies to both dimensions.
Corner radii and hub radius after back facing (Table 23, p. 82)
EN 1092-1 · EN 1092-1:2018
| Flange size | R1 min. mm | R1 max. mm | R2 min. mm |
|---|---|---|---|
| Up to and including DN 50 | 3 | 5 | 1,6 |
| Over DN 50 and up to and including DN 350 | 3 | 6 | 2,4 |
| Over DN 350 | 5 | 8 | 3,2 |
R1 minimum and maximum apply to types 33 and 35 to 37; for types 11, 12, 13, 21 and 34 see the dimension tables (Tables 10 to 21).
EN 1092-1 tolerances — questions
What tolerance applies to an EN 1092-1 flange outside diameter?
It depends on the type. For type 21 the tolerance is ±4,0 mm up to DN 250, widening to ±10,0 mm above DN 1600 to DN 2000. For all other types it is ±2,0 mm up to DN 150, ±3,0 mm to DN 500, ±5,0 mm to DN 1200, ±7,0 mm to DN 1800 and ±10,0 mm above that.
What is the wall thickness tolerance for a type 11 flange?
With the neck machined on both faces the tolerance is +1,0 / 0 mm up to DN 100, +1,5 / 0 mm over DN 100 to DN 400 and +2,0 / 0 mm above DN 400. If only one face is machined or the neck is unmachined, the corresponding values are +2,0 / 0, +2,5 / 0 and +3,5 / 0 mm.
Is the bore diameter tolerance plus or minus?
It is plus-only: +0,5 / 0 mm up to DN 100, +1,0 / 0 mm over DN 100 to DN 400, +1,5 / 0 mm over DN 400 to DN 600 and +3,0 / 0 mm above DN 600, for types 01, 02, 04, 12 and 32.
What applies to dimensions not listed in Table 22?
Clause 5.9 sends dimensions without a specified tolerance to EN 22768-1:1993. Table 22 tolerances are mandatory only for the dimensions it covers.