Duplex & Super Duplex Steel 12 Point Screws

An engineered stainless steel known for its high yield strength & decent corrosion resistance

12 Point

Duplex 2205 and Super Duplex 2507 stainless steel 12 point screws are characterized by their high yield strength, which is twice that of the annealed yield strength of typical austenitic stainless steels, like 304 and 316 stainless steel screws. Because of this, Duplex 2205 and Super Duplex 2507 steel are some of the most common grades of duplex used for screws with Super Duplex 2507 screws being the more corrosion resistant grade of the two.

Super Duplex 2507 12 point screws improved corrosion resistance lends itself well too applications prone to stress-corrosion cracking, crevice corrosion, pitting, erosion and general corrosion. Because of the properties of Duplex and Super Duplex stainless steel screws are often used in chemical processing, petrochemicals, power industry and seawater equipment.

Usage of both Duplex and Super Duplex stainless steel should be limited to temperatures below 570° F as extended elevated temperature exposure can embrittle this material.

The most common grades of Duplex screws are Duplex 2205 and Super Duplex 2507. Gain more insight on these two grades by accessing our Duplex 2205 and Super Duplex 2507 overviews or by contacting our engineering experts.

ResourcesDuplex & Super Duplex Torque Specs

Duplex Screw Types: 12 Point ScrewsButton Head Cap ScrewsFlat Head ScrewsHex Cap ScrewsPan Head ScrewsSet ScrewsSocket Head Cap ScrewsTamper Resistant Security Screws, Torx Screws


Duplex 12-Point Screw Features & Benefits

The driver of a duplex and super duplex 12-point screw uses two overlapped hexagon shapes, creating 12-points and a flanged underside. These are also referred to as ferry cap screws or 12 point flange screws. The advantages of this head style include:

  • Higher torque capability compared to a socket head cap screw
  • Lack of recess to trap fluid or debris.
  • As the heads are generally smaller than a hex, duplex 12-point screws are often used situations where installation space is tight and saving weight is critical.

The overall disadvantage is the extra cost involved in forming the heads.

The Controversy of 6 vs. 12 point Bolts

There is much debate over which bolt is better. Some say that the more points a nut or bolt has – such as a 12-point bolt - the less chance you have to round it off. And that the additional contact points of a 12 point screw give you more surface to apply load. While the jury is out as to the accuracy of this, it’s the application that should dictate whether the benefits of a 12 point screw out weight the additional costs of making them. 

 


Duplex Screw Grades, Chemistry & Specifications

Duplex Alloy 2205 

Duplex 2205, UNS S32205, is a stainless steel material, whose “Duplex” name is derived from the mixed microstructure which contains roughly equal portions of ferrite and austenite. This grade is the most popular variety and this two-phase material is a significant upgrade from 316 stainless steel in terms of both yield strength and corrosion resistance. 

Duplex Alloy 2205  Specifications: ASME SA 182, ASME SA 240, ASME SA 479, ASME SA 789, ASME SA 789 Section IV Code Case 2603, ASTM A 240, ASTM A 276 Condition A, ASTM A 276 Condition S, ASTM A 479, ASTM A 790, NACE MR0175/ISO 15156, NORSOK MDS D45 Grade F51, UNS S31803, UNS S32205, W. NR./EN 1.4462, Werkstoff 1.4462 Duplex

Duplex 2205 Chemistry

Super Duplex Alloy 2507 

Super Duplex 2507, UNS S32750, is a two-phase stainless steel and is particularly well suited for use in environments such as warm chlorinated seawater and acidic, chloride containing media. It has similiar properties to Duplex 2205 but is more corrosion resistant and performs well in moderately corrosive environments. 

Super Duplex Specifications:  EN 10216-5, ASTM A789; A790, ASTM A182 ASTM A182, ASTM A815, ASTM A240, EN 10088-2, ASTM A479, EN 10088-3 EN 10088, ISO 15156-3, NACE MR0175, Werkstoff 1.4410 S.Duplex

Super Duplex 2507

Zeron 100 / F55:

Zeron 100, UNS 32760, is commonly know as F55, which is a slight varient of Super Duplex 2507. This alloy is well suited or seawater applications.

Zeron 100/F55 Specifications: ASTM A 182, ASTM A 182 (Grade F55), ASTM A 240, ASTM A 276, ASTM A 473, ASTM A 479, ASTM A 790, ASTM A 815, ASTM A314, NORSOK MDS 055, UNS S32760, W. Nr./EN 1.4501, Werkstoff 1.4501

Zeron 100 Chemistry

  


Mechanical Data

Duplex Stainless Tensile Data

 

Duplex & Super Duplex Steel Pan Head Screws

An engineered stainless steel known for its high yield strength & decent corrosion resistance

pan head screw s

Duplex 2205 and Super Duplex 2507 pan head screws are characterized by their high yield strength, which is twice that of the annealed yield strength of typical austenitic stainless steels, like 304 and 316 stainless steel screws. Because of this, Duplex 2205 and Super Duplex 2507 steel are some of the most common grades of duplex used for screws with Super Duplex 2507 screws being the more corrosion resistant grade of the two.

Super Duplex 2507 pan head screws improved corrosion resistance lends itself well too applications prone to stress-corrosion cracking, crevice corrosion, pitting, erosion and general corrosion. Because of the properties of Duplex and Super Duplex pan head screws are often used in chemical processing, petrochemicals, power industry and seawater equipment.

Usage of both Duplex and Super Duplex stainless steel should be limited to temperatures below 570° F as extended elevated temperature exposure can embrittle this material.

The most common grades of Duplex screws are Duplex 2205 and Super Duplex 2507. Gain more insight on these two grades by accessing our Duplex 2205 and Super Duplex 2507 overviews or by contacting our engineering experts.

ResourcesDuplex & Super Duplex Torque Specs

Duplex Screw Types: 12 Point ScrewsButton Head Cap ScrewsFlat Head ScrewsHex Cap ScrewsPan Head ScrewsSet ScrewsSocket Head Cap ScrewsTorx Screws


Duplex Pan Head Screw Features and Benefits

Pan head screws are flat on top and rounded on the sides. Duplex pan head screws are ideal for:

  • Small diameter fasteners – especially when the fastener size needed is too small for a wrench.
  • When phillips or slotted drivers are desired. For many high strength specialty alloys, only slotted drives are available.
  • Low torque applications because the drivers don’t offer as much force as a wrench.
  • Large diameter head provides more clamping area.

How Are They Different from Button Head Screws?
Duplex pan head and button head screws have very similar profiles however, button head screws allow for a hex socket driver whereas pan head screws do not.

 


Duplex Screw Grades, Chemistry & Specifications

Duplex Alloy 2205 

Duplex 2205, UNS S32205, is a stainless steel material, whose “Duplex” name is derived from the mixed microstructure which contains roughly equal portions of ferrite and austenite. This grade is the most popular variety and this two-phase material is a significant upgrade from 316 stainless steel in terms of both yield strength and corrosion resistance. 

Duplex 2205 Specifications: ASME SA 182, ASME SA 240, ASME SA 479, ASME SA 789, ASME SA 789 Section IV Code Case 2603, ASTM A 240, ASTM A 276 Condition A, ASTM A 276 Condition S, ASTM A 479, ASTM A 790, NACE MR0175/ISO 15156, NORSOK MDS D45 Grade F51, UNS S31803, UNS S32205, W. NR./EN 1.4462, Werkstoff 1.4462 Duplex

Duplex 2205 Chemistry

Super Duplex Alloy 2507 

Super Duplex 2507, UNS S32750, is a two-phase stainless steel and is particularly well suited for use in environments such as warm chlorinated seawater and acidic, chloride containing media. It has similiar properties to Duplex 2205 but is more corrosion resistant and performs well in moderately corrosive environments. 

Super Duplex 2507 Specifications:  EN 10216-5, ASTM A789; A790, ASTM A182 ASTM A182, ASTM A815, ASTM A240, EN 10088-2, ASTM A479, EN 10088-3 EN 10088, ISO 15156-3, NACE MR0175, Werkstoff 1.4410 S.Duplex

Super Duplex 2507

Zeron 100 / F55:

Zeron 100, UNS 32760, is commonly know as F55, which is a slight varient of Super Duplex 2507. This alloy is well suited or seawater applications.

Zeron 100/F55 Specifications: ASTM A 182, ASTM A 182 (Grade F55), ASTM A 240, ASTM A 276, ASTM A 473, ASTM A 479, ASTM A 790, ASTM A 815, ASTM A314, NORSOK MDS 055, UNS S32760, W. Nr./EN 1.4501, Werkstoff 1.4501

Zeron 100 Chemistry

  


Mechanical Data

Duplex Stainless Tensile Data

 

Duplex & Super Duplex Steel Weld Studs

arc and capacitor no textAn engineered stainless steel known for its high yield strength & decent corrosion resistance

Duplex steel weld studs are available in a variety of fastener styles for manual (MIG, TIG) arc and capacitor discharge welding methods. Characterized by their high yield strength, which is twice that of the annealed yield strength of typical austenitic stainless steels, Duplex weld studs provide a secure, cross-sectional weld in single-sided access situations for a wide variety of extreme environments. Because of this, Duplex 2205 and Super Duplex 2507 steel are some of the most common grades of duplex used for weld studs with Super Duplex 2507 being the more corrosion resistant grade of the two.

Super Duplex 2507 weld studs' improved corrosion resistance lends itself well to applications prone to stress-corrosion cracking, crevice corrosion, pitting, erosion and general corrosion. Because of the properties of Duplex and Super Duplex stainless steel weld studs are often used in chemical processing, petrochemicals, power industry and seawater equipment.

Usage of both Duplex and Super Duplex steel should be limited to temperatures below 570° F as extended elevated temperature exposure can embrittle this material.

The most common grades of Duplex weld studs are Duplex 2205 and Super Duplex 2507. Gain more insight on these two grades by accessing our Duplex 2205 and Super Duplex 2507 overviews or by contacting our engineering experts.

ResourcesDuplex & Super Duplex Torque Specs

Duplex Screw Types: 12 Point ScrewsButton Head Cap ScrewsFlat Head ScrewsHex Cap ScrewsPan Head ScrewsSet ScrewsSocket Head Cap ScrewsTorx Screws


Duplex Steel Weld Stud Features & Benefits

Duplex weld studs available in alloy 2205 and 2507 are an ideal way to securely attached fasteners in extreme applications where reaching both sides of a structure is impossible or undesired. These weld studs can be attached by a variety of welding techniques, such as MIG or TIG welding or they can be attached by automated welding guns using Arc or Capacitor Discharge (CD) technologies.

Weld studs arc and capacitor textArc and Capacitive Discharge (CD) Weld Stud Benefits

  • Security: Unlike the peripheral weld used on a common bolt, the weld used to secure a weld stud fastener is a full cross sectional weld, so the full face of the fastener is welded in place for a strong, secure hold. And since there are no drilled holes – which weakens the structural integrity of the application – the attachment is even stronger.
  • Speed: Installing a duplex steel weld stud is a fast and simple process with a most fasteners taking less than 1 second to weld in place. Plus there is no secondary work such as drilling, polishing or grinding.
  • Simplicity: Weld studs require almost no special skills and minimal training and equipment is needed for installation. In addition, the equipment is also portable.
  • Variety: Duplex and super duplex weld studs are available in a wide variety of fastener styles including (but not limited to) fully threaded, partially threaded, full base, reduced base, long, tapped base, and shoulder thread to name a few.

 Weld Stud Methods

how weld stud works


Duplex Weld Stud Grades, Chemistry & Specifications

Duplex Alloy 2205 

Duplex 2205, UNS S32205, is a stainless steel material, whose “Duplex” name is derived from the mixed microstructure which contains roughly equal portions of ferrite and austenite. This grade is the most popular variety and this two-phase material is a significant upgrade from 316 stainless steel in terms of both yield strength and corrosion resistance. 

Duplex 2205 Specifications: ASME SA 182, ASME SA 240, ASME SA 479, ASME SA 789, ASME SA 789 Section IV Code Case 2603, ASTM A 240, ASTM A 276 Condition A, ASTM A 276 Condition S, ASTM A 479, ASTM A 790, NACE MR0175/ISO 15156, NORSOK MDS D45 Grade F51, UNS S31803, UNS S32205, W. NR./EN 1.4462, Werkstoff 1.4462 Duplex

Duplex 2205 Chemistry

Super Duplex Alloy 2507 

Super Duplex 2507, UNS S32750, is a two-phase stainless steel and is particularly well suited for use in environments such as warm chlorinated seawater and acidic, chloride containing media. It has similiar properties to Duplex 2205 but is more corrosion resistant and performs well in moderately corrosive environments. 

Super Duplex 2507 Specifications:  EN 10216-5, ASTM A789; A790, ASTM A182 ASTM A182, ASTM A815, ASTM A240, EN 10088-2, ASTM A479, EN 10088-3 EN 10088, ISO 15156-3, NACE MR0175, Werkstoff 1.4410 S.Duplex

Super Duplex 2507

Zeron 100 / F55:

Zeron 100, UNS 32760, is commonly know as F55, which is a slight varient of Super Duplex 2507. This alloy is well suited or seawater applications.

Zeron 100/F55 Specifications: ASTM A 182, ASTM A 182 (Grade F55), ASTM A 240, ASTM A 276, ASTM A 473, ASTM A 479, ASTM A 790, ASTM A 815, ASTM A314, NORSOK MDS 055, UNS S32760, W. Nr./EN 1.4501, Werkstoff 1.4501

Zeron 100 Chemistry

  


Mechanical Data

Duplex Stainless Tensile Data

 

Duplex & Super Duplex Steel Torx Screws

An engineered stainless steel known for its high yield strength & decent corrosion resistance

torx s

Duplex 2205 and Super Duplex 2507 stainless steel Torx screws are characterized by their high yield strength, which is twice that of the annealed yield strength of typical austenitic stainless steels, like 304 and 316 stainless steel screws. Because of this, Duplex 2205 and Super Duplex 2507 steel are some of the most common grades of duplex used for screws with Super Duplex 2507 Torx screws being the more corrosion resistant grade of the two.

Super Duplex 2507 Torx screws improved corrosion resistance lends itself well too applications prone to stress-corrosion cracking, crevice corrosion, pitting, erosion and general corrosion. Because of the properties of Duplex and Super Duplex stainless steel screws are often used in chemical processing, petrochemicals, power industry and seawater equipment.

Usage of both Duplex and Super Duplex stainless steel should be limited to temperatures below 570° F as extended elevated temperature exposure can embrittle this material.

The most common grades of Duplex screws are Duplex 2205 and Super Duplex 2507. Gain more insight on these two grades by accessing our Duplex 2205 and Super Duplex 2507 overviews or by contacting our engineering experts.

ResourcesDuplex & Super Duplex Torque Specs

Duplex Screw Types: 12 Point ScrewsButton Head Cap ScrewsFlat Head ScrewsHex Cap ScrewsPan Head ScrewsSet ScrewsSocket Head Cap ScrewsTamper Resistant Security Screws, Torx Screws


Duplex Torx Screw Features and Benefits

Duplex Torx screws are characterized by a 6-point star-shaped pattern, also called a star drive, spined socket or hexalobular (ISO 10664). Where Phillips heads were designed to cause the driver to cam-out (prevent overtightening), Torx screws were designed resist cam-out. This feature allows Duplex Torx screws to provide increased torque as well as better torque transfer between driver and fasteners. This feature also helps to reduce wear on driver bits.

Duplex Torx Screw Advantages

  • Resistant to cam out (process by which a screwdriver slips out of the head)
  • Duplex Torx screws are more difficult to strip
  • Increased tamper resistance as a star driver isn’t as common
  • Driver insert is less susceptible to damage when over torqued than Allen head

 


Duplex Screw Grades, Chemistry & Specifications

Duplex Alloy 2205 

Duplex 2205, UNS S32205, is a stainless steel material, whose “Duplex” name is derived from the mixed microstructure which contains roughly equal portions of ferrite and austenite. This grade is the most popular variety and this two-phase material is a significant upgrade from 316 stainless steel in terms of both yield strength and corrosion resistance. 

Duplex 2205 Specifications: ASME SA 182, ASME SA 240, ASME SA 479, ASME SA 789, ASME SA 789 Section IV Code Case 2603, ASTM A 240, ASTM A 276 Condition A, ASTM A 276 Condition S, ASTM A 479, ASTM A 790, NACE MR0175/ISO 15156, NORSOK MDS D45 Grade F51, UNS S31803, UNS S32205, W. NR./EN 1.4462, Werkstoff 1.4462 Duplex

Duplex 2205 Chemistry

Super Duplex Alloy 2507 

Super Duplex 2507, UNS S32750, is a two-phase stainless steel and is particularly well suited for use in environments such as warm chlorinated seawater and acidic, chloride containing media. It has similiar properties to Duplex 2205 but is more corrosion resistant and performs well in moderately corrosive environments. 

Super Duplex 2507 Specifications:  EN 10216-5, ASTM A789; A790, ASTM A182 ASTM A182, ASTM A815, ASTM A240, EN 10088-2, ASTM A479, EN 10088-3 EN 10088, ISO 15156-3, NACE MR0175, Werkstoff 1.4410 S.Duplex

Super Duplex 2507

Zeron 100 / F55:

Zeron 100, UNS 32760, is commonly know as F55, which is a slight varient of Super Duplex 2507. This alloy is well suited or seawater applications.

Zeron 100/F55 Specifications: ASTM A 182, ASTM A 182 (Grade F55), ASTM A 240, ASTM A 276, ASTM A 473, ASTM A 479, ASTM A 790, ASTM A 815, ASTM A314, NORSOK MDS 055, UNS S32760, W. Nr./EN 1.4501, Werkstoff 1.4501

Zeron 100 Chemistry

  


Mechanical Data

Duplex Stainless Tensile Data

 

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