2768-mk-e |top|: Iso

| Part | Title | Purpose | |------|-------|---------| | | General tolerances for linear and angular dimensions | Defines tolerance classes (f, m, c, v) for sizes, radii, chamfers, and angles | | ISO 2768-2 | General tolerances for geometrical features | Defines tolerance classes (H, K, L) for straightness, flatness, parallelism, perpendicularity, symmetry, runout |

GENERAL TOLERANCES: ISO 2768-MK-E Alternatively: iso 2768-mk-e

These values apply per 100 mm of length. For longer lengths, the tolerance is prorated but limited by the maximum deviation. | Part | Title | Purpose | |------|-------|---------|

| Nominal Range (mm) | Straightness / Flatness (± mm) | Perpendicularity (± mm) | |--------------------|--------------------------------|-------------------------| | ≤10 | 0.05 | 0.1 | | >10 to 30 | 0.1 | 0.2 | | >30 to 100 | 0.2 | 0.3 | | >100 to 300 | 0.3 | 0.4 | | >300 to 1000 | 0.4 | 0.5 | | >1000 to 3000 | 0.5 | 0.6 | Circular runout – 0

– Same values as perpendicularity. Circular runout – 0.2 mm (class K). Total runout – Not defined; must be specified individually. Example: A 200 mm long machined surface without a flatness callout → allowed flatness deviation = 0.3 mm. 3.3 "E" – External Radii & Chamfer Heights (ISO 2768-1 Annex A) The "E" instructs that tolerances for external radii and chamfer heights follow the same "M" class limits as linear dimensions, but applied to the radius or chamfer size.

| Tolerance Class | Straightness & Flatness (mm per 100 mm) | Perpendicularity & Symmetry (mm per 100 mm) | Runout (mm) | |----------------|------------------------------------------|----------------------------------------------|--------------| | | 0.2 | 0.5 | 0.2 |

| Feature Type | Rule | |--------------|------| | Length, width, height | ± mm from "M" linear table | | Hole diameter | Not covered (size tolerance must be given individually unless it's a general dimension) | | Hole position | Covered by "K" position tolerance (0.5 mm per 100 mm) | | Flatness of a surface | 0.2 mm per 100 mm (class K) | | Perpendicularity of a shoulder | 0.5 mm per 100 mm (class K) | | External fillet radius R5 | ±1.0 mm (since 5 mm is in >3–6 range, "E") | | Chamfer C2 | ±0.5 mm (from "E" table) |