HEX NUT DIMENSIONS - METRIC FINE PITCH THREAD

Dimensions of metric hex nuts with fine pitch thread are shown in the following chart according to ISO 8673, ISO 8674 and ISO 4759-1 standards.

Some important notes from the ISO standards about hex nuts with metric fine thread:

- ISO 8673 specifies the characteristics of hex nuts, style 1, with metric fine pitch thread, with nominal thread diameters d from 8 mm up to and including 64 mm, with product grade A for threads d ≤ M16 and product grade B for threads d > M16.

- Mechanical properties of ISO 8673 hex nuts with fine pitch thread: (Steel - d ≤ M39 - Property class 6, 8 , d ≤ M16 - Property class 10) , ( Stainless steel - d ≤ M24: Property class A2-70, A4-70 , M24 < d ≤ M39 - Property class A2-50, A4-50 )

- ISO 8674 specifies the characteristics of hex nuts, style 2, with metric fine pitch thread, with nominal thread diameters d from 8 mm up to and including 36 mm, with product grade A for threads d ≤ M16 and product grade B for threads d > M16.

- Mechanical properties of ISO 8674 hex nuts with fine pitch thread: Steel - d ≤ M16 - Property class 8 and 12, d ≤ M36 - Property class 10

Calculator:

INPUT PARAMETERS
Nominal metric hex nut size

 


Dimensions of Metric Hex Nuts with Fine Pitch Thread
Metric Nut Dimensions 
Size Product
Grade
Standard Pitch c da dw e m mw s
max min max min min min max min min max min
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Note 1: Dimensions are in mm.
Note 2: Requirements for electroplating are covered in ISO 4042 for steel nuts
Note 3: Requirements for nonelectrolytically applied zinc flake coatings are covered in ISO 10683 for steel nuts.
Note 4: Non-preferred threads according to ISO standards: M10 x 1.25, M12 x 1.25, M14 x 1.5, M18 x 1.5, M20 x 2, M22 x 1.5, M27 x 2, M33 x 2, M39 x 3, M45 x 3, M52 x 4, M60 x 4.
Note 5: Thread tolerance of hex thin nuts is 6H.

Definitions:

Product Grade A, Grade B and Grade C: The product grades refer to the size of the tolerances where grade A is the most precise and grade C is the least precise as defined in the ISO 4759-1:2000 standard.


Supplements:



Link Usage
Metric Thread Size and Tolerance Calculator Calculates basic major, minor and pitch diameters of the metric external (bolt) thread and internal (nut) thread according to ISO 724:1993 standard. In addition to basic size calculations, tolerance calculations of different tolerance classes can be done according to ISO 965-1:1998 and ISO 965-2:1998 standards.
Hex Nut Dimensions - Metric Coarse Pitch Thread Shows dimensions of a selected metric hex nut with coarse pitch thread.
Nut Grades, Identification Markings and Strength (Metric) Shows proof strength and Vickers and Brinell hardness values of metric nuts made of carbon steel and alloy steel.

Reference:
  • ISO 8673:1999, Hexagon nuts, style 1, with metric fine pitch thread — Product grades A and B
  • ISO 8674:1999, Hexagon nuts, style 2, with metric fine pitch thread — Product grades A and B
  • ISO 4759-1:2000, Hexagon nuts — Bolts, screws, studs and nuts — Product grades A, B and C