What are duplex fasteners?
Austenitic-ferritic stainless steels are alloys that contain both austenite and ferrite in an almost equivalent proportion. Hence, they are known as duplex grades. Duplex Fasteners are preferred in highly demanding applications because they have higher mechanical strength along with excellent to good corrosion resistance properties.
What is a duplex bolt?
Bolts are threaded (shank) fasteners with a head (that may or may not be recessed). Generally, they tend to have higher corrosion resistance properties, due to the inclusion of nickel, chromium and molybdenum in their alloy.
What are the benefits of using duplex hex bolts?
They exhibit good mechanical properties at room temperature, even when the shank of the screws is thinner. Moreover, the minimum yield strength of DSS hex bolts is almost two times that of a conventional austenitic alloy. Fasteners made from duplex alloys have good resistance to stress corrosion cracking.
Various types of Duplex fasteners
Duplex Hex Bolts
DSS J-bolts
Duplex Alloy Countersunk Bolts
Duplex Stainless Steel U-bolts
Duplex Alloy Friction Grip Bolts
Duplex Stainless Steel Square Bolts
Duplex Eye Bolts
Duplex Steel Tie Bolts
DSS T Bolts
Duplex Spring Washer
Duplex Steel Star Washer
DSS Machined Washer
Duplex Stainless Steel Heavy Hex Head Bolt
Duplex Alloy Heavy Hex Bolt
Duplex Stainless Plain Washer
How do you calculate duplex heavy hex bolts torque?
The torque of bolts is calculated using the following formula –
T = KDP
Where T = Torque
K = torque coefficient (dimensionless)
D = nominal diameter in inches
P = bolt clamp load in pounds
Do duplex stainless steel fasteners rust?
Like most metals, if exposed to stronger reagents (acid or base), these fasteners may get corroded. However, compared to most austenitic or ferritic stainless steel grades, duplex stainless steel alloys have a considerably higher PREN (pitting resistance equivalent number) value. A higher PREN value indicates excellent resistance to pitting. Grade 2205 is a mid-range Duplex variety whose PREN value ranges between 28 – 38.
What is the application of Duplex Carriage Bolt?
Duplex Carriage Bolt are ideal in structural applications. They aid in stabilizing structures temporarily or permanently in materials like wood, concrete or metal. They have a good performance and resist corrosion in moderately high-temperature environments.
Duplex Eye bolts vs DSS U bolt
DSS U bolts are threaded fasteners that are used with nuts to fit objects together. Unlike Eye bolts that have a loop at one end, hence they could be used with one (where one end is already attached to a material) or 2 nuts in an assembly.
The following is a list of duplex fasteners grades
