What does ISO 2768-2 cover?

ISO 2768-2 specifies general tolerances for form and position (geometrical tolerances) that apply when no individual tolerance is indicated on a drawing. It covers straightness, flatness, perpendicularity, symmetry, and circular runout.

What are the tolerance classes in ISO 2768-2?

ISO 2768-2 defines three tolerance classes: H (most precise), K (medium), and L (coarsest). The class is indicated on the drawing title block, e.g. ISO 2768-mK means ISO 2768 part 1 class m, part 2 class K.

How is ISO 2768-2 indicated on a drawing?

The standard is referenced in the drawing title block as 'ISO 2768-mK' where the lowercase letter is the ISO 2768-1 (dimensional) class and the uppercase letter is the ISO 2768-2 (geometrical) class.

Does ISO 2768-2 apply to all features?

ISO 2768-2 applies only to features that do not have individual geometrical tolerances specified. Features with explicit GD&T symbols on the drawing are controlled by those specific tolerances instead.

What is the difference between ISO 2768-1 and ISO 2768-2?

ISO 2768-1 covers general dimensional (linear and angular) tolerances, while ISO 2768-2 covers general geometrical (form and position) tolerances. They are complementary and usually referenced together.

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一般公差 ISO 2768-2 計算器

查詢 ISO 2768-2 的幾何（形狀與位置）公差。選擇公差等級、特徵類型與公稱範圍。

ISO 2768-2 H / K / L 等級形狀與位置

結果

一般公差

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公差等級

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特徵類型

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公稱範圍

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注意

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直線度 / 平面度公差

適用於直線特性與平面。公稱範圍指表面之較長邊或特性之長度。

範圍 (mm)	H	K	L
≤ 10	0.02	0.05	0.1
10 – 30	0.05	0.1	0.2
30 – 100	0.1	0.2	0.4
100 – 300	0.2	0.4	0.8
300 – 1000	0.3	0.6	1.2
1000 – 3000	0.4	0.8	1.6

垂直度公差

適用於公稱上垂直於基準面的特徵。公稱範圍指角度的較短邊。

範圍 (mm)	H	K	L
≤ 100	0.2	0.4	0.6
100 – 300	0.3	0.6	1.0
300 – 1000	0.4	0.8	1.5
1000 – 3000	0.5	1.0	2.0

對稱度公差

範圍 (mm)	H	K	L
≤ 100	0.5	0.6	0.6
100 – 300	0.5	0.6	1.0
300 – 1000	0.5	0.8	1.5
1000 – 3000	0.5	1.0	2.0

圓跳動公差

級別	公差 (mm)
H	0.1
K	0.2
L	0.5

⚠️ 注意： ISO 2768-2 一般公差僅在圖面上未標註特定幾何公差時適用。具有明確 GD&T 標註的特徵將優先於這些數值。