CEN - EN ISO 898-6
Mechanical Properties of Fasteners - Part 6: Nuts with Specified Proof Load Values - Fine Pitch Thread
|Publication Date:||1 November 1995|
|ICS Code (Nuts):||21.060.20|
This part of ISO 898 specifies the mechanical properties of nuts with specified proof load values when tested at an ambient temperature range of + 10 °C to + 35 °C. Mechanical and physical properties will vary with respect to temperature and property class.
Products conforming to the requirements of this part of ISO 898 are evaluated only at the ambient temperature range and may not retain the specified physical properties at higher and lower temperatures.
At temperatures higher or lower than the ambient temperature range, a significant change in properties may occur. When fasteners are to be used above or below the ambient temperature range, it is the responsibility of the user to ensure that the mechanical and physical properties are suitable for his particular service conditions.
This part of ISO 898 applies to nuts
- with nominal thread diameters, d, from 8 mm up to and including 39 mm (fine pitch thread);
- of triangular ISO thread and with diameters and pitches in accordance with ISO 68 and ISO 262 (fine pitch thread);
- with diameter/pitch combinations in accordance with ISO 261 (fine pitch thread);
- with thread tolerances 6H in accordance with ISO 965-1 and 965-2 (see note 2);
- with specific mechanical requirements;
- with widths across flats as specified in ISO 272;
- with nominal heights greater than or equal to 0,5d1);
- made of carbon steel or alloy steel (see note 1).
It does not apply to nuts requiring special properties such as
- prevailing torque performance (see ISO 2320);
- corrosion resistance (see ISO 3506);
- ability to withstand temperatures above + 300 °C or below - 50 °C. (However, see note 1.)
1 Nuts made from free-cutting steel should not be used above + 250 °C.
2 With thread tolerances other or larger than 6H. a decrease in the stripping strength should be considered (see table 1).
1) In ISO 898:1988, the symbol D was used