S-BT Threaded Fastener Specification

Table Of Contents
page 32 Specifications
Corrosion information:
TheS-BTstainlesssteelfastenersaremadefromtheduplexstainlesssteeltype
1.4462,whichisequivalenttoAISI316and318LNsteelgrade.Thisgradeof
stainlesssteelisclassiedinthecorrosionresistanceclassIVaccordingtoDIN
EN1993-1-4:2015,whichmakesthematerialsuitableforaggressiveenvironments
likeincoastalandoffshoreapplications.Themicrostructuresofduplexstainless
steelsconsistofamixtureofausteniteandferritephases.Comparedtothe
austeniticstainlesssteelgrades,duplexstainlesssteelsaremagnetic.Thesurface
oftheS-BTstainlesssteelfastenersiszinc-coated(anti-frictioncoating)inorder
toreducethethreadformingtorquewhenthestudisscrewedinintothebase
material.
The coating of the carbon steel S-BT fasteners consists of an electroplated
Zn-alloyforcathodicprotectionandatopcoatforchemicalresistance(Duplex-
coating).Thethicknessofthecoatingis35μm.Thisproductisdesignedforuse
incorrosivecategoriesC1,C2andC3accordingthestandardENISO9223.For
highercorrosioncategoriesstainlesssteelfastenersshouldbeused.
Note:
ETA-20 / 0530allowstheuseofcarbonsteelthreadedstudswithduplexcoating
onlyindryindoorenvironment(C1acc.toENISO9223) .
Incaseofadrillthroughholeorapilotholeinthinbasematerial,reworkofthe
coatingonthebacksideoftheplate/prolemaybeneeded.
S-BT-_________AN 6 S-BT-_________SN 6
CorrosivitycategoryC C3
mediumcorrosive
C5
veryhighcorrosive
Drill hole type and
basematerialthicknesst
II
1)
Topside
protection
Backside
protection
Topside
protection
Backside
protection
Drillthroughhole
3mm[0.12"]≤t
ll
<6mm[0.24"]
✘
2)
✘
2)
Pilothole
6mm[0.24"]≤t
ll
<7mm[0.28"]
3)
Pilothole
t
ll
≥7mm[0.28"]
1)
Realbasematerialthickness,notnominalmaterialthicknessormaterialthicknesswithcoating.
2)
Damageofthecoatingonthebacksideoftheplate/prolerequireareworkofthecoating.
3)
Damageofthecoatingonthebacksideoftheplate/prolerequireareworkofthecoating,ifthedril-
lingtoolsSFBT22-AorSFBT18-Awereusedfordrillingtheborehole.IfthetoolSBT4-A22wasused
fordrillingtheborehole,nodamageofthecoatingonthebacksideoftheplate/prolewilloccur.
3.2.9 Thickness of fastened material t
l
S-BT-______/7______ 1.6mm[0.063"]≤t
I
≤7.0mm[0.28"]
S-BT-______/15_____ 1.6mm[0.063"]≤t
I
≤15.0mm[0.59"]
t
I
L
g
t
NUT