scope:

This European Standard is applicable to the selection of bolting for equipment subject to the Pressure
Equipment Directive 97/23/EC.
It specifies standards and additional requirements for dimensions, materials and technical conditions of delivery for bolting.
The bolting of this standard is selected for the combined use with flanges according to the series EN 1092 (PN designated flanges) and the series EN 1759 (Class designated flanges).
The selection is based on commonly used materials, bolts and nuts. It covers temperature ranges, based on PN or Class, of the general service of standard flanges.
When selecting bolting according to this European Standard other parameters such as type of fluids, corrosion hazards and relaxation at elevated temperatures shall be taken into account.
The purpose of this standard is to provide a selection of most commonly used bolting types and bolting material combinations to offer a tool for easy selection of suitable bolting for pressure equipment.
It is not the intention to specify all possible applications but to give guidance on the most commonly
applications. According to this, e.g. material in the creep range are not covered in this standard but some bolting materials listed are suitable to be used in this temperature range.
NOTE 1 Special services and ambient conditions may require the application of coatings. It is at the discretion of the user to decide on this. Depending on the coating used, a verification of the temperature ranges given in Table 3 may be required.