Stud bolt is basically a threaded rod. Double end stud bolt has threads on both the ends it can fasten two flanges more effectively. They are mostly used while attaching flanges or pipes together. Length of thread varies according to requirement.

There are vairous types of Bolts viz :

Full Threaded StudDouble Threaded StudTap Stud


  • Cold Forged Fasteners, Hot Forged Fastener, C-Machined Stud Bolts, CNC Machined Stud Bolts, Custom Machined Stud Bolts, Threaded Stud Bolts, Non-Threaded Stud Bolts, Bar Stock Machined Stud Bolts.

Size Range

  • 5/16″ – 6″ according to ANSI / ASME
  • M8 – M150 according to ISO / DIN
  • Max Length 6000mm


  • Coarse, Fine, UNC, UNF, UN, BSW, Acme Threads with Half Thread, Full Thread & Double End Thread Configuration.


Electro Zinc PlatingHot Dip GalvanizingPtfe Fluorocarbon Coating
AluminizingCeramic Filled Fluorocarbon CoatingNickel Plating
Mechanical Zinc CoatingElectro Zinc Colbalt PlatingElectro Zinc Nickel Plating
Phosphate CoatingElectro Less Nickel PlatingElectro Cadmium Plating
Dacromet 320 500 CoatingPickled Passivated FastenersSilver Plating
Zinc PlatingMechanical GalvanizationZN Phosphating
MN PhosphatingCadium PlatingZinco-Nickel Plating
Nickel Electroless PlatingBurnishingGeomet
Customised CoatingCeramic Filled Fluorocarbon Coating 

Dimensional Standards

  • Materials – ASTM / ASME / BSI / ISO / Nace / AFNOR / DIN / AISI
  • Hexagonal Bolts – ANSI B18.2.1, ANSI B18.2.3.1M, DIN 931, DIN 933, BS 1768, UNI 5731, UNI 5737, UNI 5739, ISO 4014, ISO 4017, BS 1769, BS 3692
  • Socket/Slotted Set Screws – DIN 913, DIN 914, DIN 915, DIN 916, DIN 551, DIN 553, DIN 438, BS 4168
  • Socket/Slotted Countersunk Screws – DIN 963, DIN 7991, BS 4168, BS 1981, BS 483, BS 2470
  • Socket Cap Screws – ANSI B18.3, B18.3.1M, DIN 912, DIN 6912, DIN 7984, ANSI B18.3, ISO 4762, UNI 5931, BS 2470, BS 4168
  • Stud Bolts – ASME B18.2.1, DIN 976, DIN 938, DIN 939, DIN 2510, BS 4439, BS 2693, BS4882
  • Nuts – ANSI B18.2.2, ANSI B18.2.4.6M, DIN 934, DIN 936, BS 1768, BS 1769, BS 1083, BS 3692, ISO 4032, ISO 4033, ISO 4035, UNI 5587, UNI 5588, UNI 5589
  • Washers – ASME B18.22.1, ASTM F436, ISO 7089, DIN 125, DIN 9021, BS 4320, BS 3410, DIN 127, BS 4464, BS 1802, UNI 6952
  • Common Grades – SAE J429 Gr 5, SAE J429 Gr 8, ASTM A307 Gr A, ASTM A307 Gr B, ASTM A325 Type 1, ASTM A490 Type 1, ASTM A193 Gr B7, ASTM A193 Gr B7M, ASTM A193 Gr B16, ASTM A193 G B8, ASTM A320 Gr L7, ASTM A193 G B8M, BS 3692 Gr 4.8, BS 3692 8.8, BS 3692 Gr 10.9, BS 3692 12.9, JIS B1188 Class F8T, JIS B1185 Class F10T, SS304, SS316, SS316L, BS EN ISO 3506 A2-50, BS EN ISO 3506 A2-70, BS EN ISO 3506 A2-80, BS EN ISO 3506 A4-50, BS EN ISO 3506 A4-70, BS EN ISO 3506 A4-80

Types of Studs

Continuous Thread Studs

Type 1
Type 2
Type 1 Continuous Stud
Type 2 Continuous Stud
Continuous-thread studs are threaded from end to end and are often used for flange bolting with two nuts applied.
Type 1 – General purpose. The length of this type is measured from end to end. Threads are UNRC-2A.Type 2 – Studs for temperature-pressure piping. These studs are made to the dimensional standard requirements of ANS B16.5 and have a length measurement requirement different from all other studs, i.e., the length is measured from first thread to first thread, exclusive points. Points are flat and chamfered. Threads are UNRC-2A for all sizes 1 in. and under and 8UNR-2A for all sizes over 1 in.

Tap End Studs

Tap End Studs

Tap-end studs have a short thread on one end, called the tap end which is threaded to a Class NC5 or Class UNRC-3A fit. This end is for screwing into a tapped hole. The other or nut end is threaded with a Class UNRC-2A fit. Length of the stud is measured overall. The tap end has a chamfered point, but the nut end may have either a chamfered or round point, at the manufacturer’s option. Tap-end studs are available in four types, as follows:
Type 1 – Unfinished, have a full diameter but no standard body tolerances.
Type 2 – Finished, having either an undersize body with rolled threads or a full-size body with cut threads, at the manufacturer’s option. The body portion will be finished to a maximum Class 2A pitch diameter or maximum basic major diameter of the nut-end thread.
Type 3 – Finished, full-body, having tolerances equal to that on major diameter of Class 2A threads.

Type 4 – Finished close-body, milled or ground to tolerances specified by the user.

Double End Studs

Tap End Studs

Double-end studs have equal-length threads on each end to accommodate a nut and are threaded to a Class 2A fit. Length of stud is measured overall. Both ends have chamfered points, but round points may be furnished on either or both ends at the manufacturer’s option, This style is furnished in the same four types listed for tap-end studs. Double-end studs are used for flange bolting or other applications where torching from both ends is necessary or desirable. Most steel grades not heat treated or quenched and tempered can be furnished on special order for production quantities. Only the Type 2 continuous thread studs made to specification ASTM A193 grade B7 are stocked in a full range of sizes.