ISO 3506-1979 pdf free.Corrosion-resistant stainless steel fasteners — Specifications.
SCOPE AND FIELD OF APPLICATION:This International Standard gives specifications for bolts,screws,studs and nuts made from austenitic,ferritic andmartensitic grades of corrosion-resistant stainless steels.lt is applicable only to fastener components after com-pletion of manufacture,with nominal thread diameters from 1,6 up to andincluding 39 mm,of any triangular Iso metric threads according tolso 68 and with diameters and pitches according toISO 262,of any shape; and additionally for nuts of any shape provided that width across flats or outside diameters is not lessthan 1,45 times nominal diameter , and effective threadengagement is at least 0,6 timesnominal diameter.
This International Standard does not define corrosion oroxidation resistance in particular environments. it doesspecify grades for fasteners made from corrosion resistantstainless steets.Some have mechanical properties allowinguse at temperatures down to 200 °C in air. Some haveoxidation resistance allowing use at temperatures up to 800°C in air.
Acceptable corrosion and oxidation performances andmechanical property values allowing use at elevated or subzero temperatures must be the subject of agreement betweenuser and manufacturer wherever appropriate to the proposedservice environment.
All hexagon head screws and bolts and socket cap screwsof M5 thread diameter and greater shall be clearly markedin accordance with the designation system given in.Thismarking can be applied to other types of bolts and screwswhere it is technically possible to do so on the head portiononly.
The marking shall include the steel grade and property classand also the manufacturer’sidentification mark (seefigure 1).Additional marking can be applied at the option of the manufacturer or at the specific request of the pur-chaser.This additional marking should not be liable tocause confusion with any other standardized marking oridentification. Studs and other fasteners:Marking of studs and other fasteners shall be agreed betweenuser and manufacturer.
Nuts shall be marked with the steel grade and propertyclass,if necessary, and with the manufacturer’s identi-fication mark in the case of nuts of M5 nominal threaddiameter and greater (see figure 2), where this is technicallypossible for the manufacturer. Marking of one nut face isacceptable and shall be by indentation only when appliedto the bearing surface of the nuts.Alternatively , markingon the side of the nuts is permissible. Property classmarking and designation of nuts is necessary where the nutsdo not meet the minimum proof load stress of the highestproperty class for the steel grade.ISO 3506 pdf download.