SDC Clean-Bolt Series

No lubricant grease or oil, Ag (silver) plating nor dry film lubricant are required to prevent galling.
Stainless steel fasteners are particularly susceptible to thread galling.
During the tightening of the fastener, pressure builds between the contacting and sliding thread surfaces and breaks down the protective oxide coatings. With the absence of the protective oxide, interface metal high points shear or lock together. In the extreme, galling leads to seizing and welding.
SDC Clean bolt is the most effective fastener to withstand wear and galling, while meeting corrosion resistance, when there is need for cleanness as in semiconductor devices or sanitation as in food or pharmaceutical processing, which precludes the use of lubricants.
Hex Socket Cap Screw
Hex Bolt, Hex Nut
(1)
Semiconductor, FPD and Solar Panel
(2)
Pharmaceutical and Cosmetic Chemicals
(3)
Food and Beverage etc...
(4)
Hard disk drive
(1)
No risk of contamination generated by lubricant, coating and plating
(2)
Extends life of frequently screwed fastener and reduces damage on equipments fastened
(3)
Eliminates idle time of maintenance and assembling process by "galling" fastener after heating and cryogenic process cycles (recommended to use under 300 ºC or 572 ºF)
(4)
Maintains good corrosion resistant and nonmagnetic properties
(5)
Available in a wide range of fastener type and size
(6)
Other materials are available upon request
Tensile strength
  
Fatigue strength

Material: S31603(316L)
There is no crack nor peeled in case
hardened layer despite the base mate -
rial was plastically deformed with high
load impact. The case hardened layer
followed the base material deformation.
Untreated bolt
SDC Clean Bolt

Untreated bolt galled and broke after
6 cycles of thread tightening

SDC clean Bolt has no problems after
100 cycles of thread tightening
Comparison table
  Silver plated bolt SDC Clean Bolt
Preventing galling 〇 / Good ◎ / Excellent
Oxidation resistance × / Poor 〇 / Good
Storage in ambient air × / Poor ◎ / Excellent
Repeated use 〇 / Good ◎ / Excellent
Resistance to
surface peeling		 × / Poor ◎ / Excellent
Free of silver contamination × / Poor ◎ / Excellent
Conductivity ◎ / Excellent 〇 / Good
  Silver plated bolts have problems
with the plated film peeling and
with atmospheric oxidation
(discoloration)		 The SDC Clean Bolt can be used
repeatedly without peeling and
does not oxidize
Condition of the threaded area after ten cycles of tightening and loosening
Silver plated bolt
  
SDC Clean Bolt

Peeling of the silver-plated surface was observed
(You can see how the plating has come off)

There is no risk of contamination by peeled plated surface thanks to the diffusion-based surface hardening technology
(There are no visual damages)
Condition after storage in the ambient air (90 days indoors)
Silver plated bolt
  
SDC Clean Bolt

Oxidation occurs in the silver-plated area
(You can see that it turned brown)

No specific storage method is required
(There are no visual changes)
Material:
SS316 (S31600) or SS316L (S31603)
(Other materials are available upon request)
Surface Treatment:
SDC plasma surface-hardening process
Options (available upon request):
Vent hole for vacuum chamber
Extra precision cleaning and packaging for clean room
ANSI, DIN and other standards
Non standard customer designed parts according to engineering drawing
Item Description in Metric:
Hex Bolt, Hex Nut
Hex Socket Cap Screw
Hex Socket Set Screw