Weld Stud Ferrule Sizing Chart

Ceramic ferrules are required for every drawn arc weld stud installation. The ferrule surrounds the base of the stud during welding, contains the molten metal and arc flash, and shapes the fillet weld collar. Matching the right ferrule to your stud diameter and application is critical -- an incorrect ferrule causes incomplete fusion, flash scatter, or loss of the weld collar.

Use this chart to match common ferrule part numbers to your stud welding application. If you’re not sure which ferrule you need, send your stud diameter and application (direct plate, thru-deck, angle weld) and we’ll confirm the correct ferrule and quote price and lead time.

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How to Choose the Right Ferrule

• Full Diameter (F) ferrules are used when the weld base is a nominal diameter (common for headed concrete anchor studs and shear connectors in direct plate applications).
• Pitch Diameter (P) ferrules are used when the weld base equals the pitch diameter of the fastener (typically for pitch-diameter style threaded weld studs).
• Thru Deck (TD) ferrules are used for welding shear connectors through metal deck in composite construction. The longer base profile seats on the beam flange through the deck opening.
• Inside Angle (I) ferrules are used when the stud must be welded in an inside corner where standard ferrule geometry cannot seat properly.
• Outside Angle (O) ferrules are used for welding to curved or outside-corner surfaces.
• Heavy Duty (H) ferrules provide a heavier ceramic profile for higher-energy drawn arc applications requiring more fillet weld containment.

Note: Ferrules are disposable, mass-manufactured ceramic components. Tolerances can be greater than machined parts, so it’s not recommended to fixture off a ferrule when exact stud location is required.

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Full Diameter Ferrules (F)

Standard ferrule for headed concrete anchor and shear connector studs in direct plate applications. Match the ferrule P/N prefix number to the stud shank nominal diameter (in hundredths of an inch): 25 = 1/4", 31 = 5/16", 37 = 3/8", 43 = 7/16", 50 = 1/2", 62 = 5/8", 75 = 3/4", 87 = 7/8", 1 = 1".

Pitch Diameter Ferrules (P)

Used with pitch diameter (TP) threaded weld studs where the weld base is the pitch diameter, not the full nominal diameter. See the Threaded Weld Studs Selection Guide for guidance on TP vs. TF vs. CS threaded stud types.

Heavy Duty Ferrules (H)

Thru Deck Ferrules (TD)

Required for welding shear connectors through metal deck in composite construction. The extended base profile allows the ferrule to contact the beam flange through the deck opening. Do not substitute standard (F) ferrules for thru-deck applications -- the ferrule will not seat correctly and the weld collar will not form properly.

Note: “Zip Ferrules” are collated sleeve packages (e.g., 75TDZ is a sleeve package of 75TD ferrules). Zip packaging improves handling speed for high-volume thru-deck welding.

Inside Angle Ferrules (I)

For welding studs in inside corners or fillets where a standard round ferrule base cannot seat flat. The inside angle ferrule has a radiused base profile that matches the inside corner geometry.

Outside Angle Ferrules (O)

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Related Weld Stud Resources

• Weld Stud Selection Guide -- all stud types, drawn arc vs. CD process, materials
• Headed Concrete Anchors and Shear Connectors Selection Guide -- diameter, after-weld length, composite deck
• Threaded Weld Studs Selection Guide -- which ferrule type matches TP, TF, and CS threaded studs
• Deformed Bar Anchors Selection Guide
• Nelson Weld Stud Cross-Reference -- Cox and Bluearc equivalents for Nelson H4L studs

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Need Help Matching Ferrules to Your Studs?

Send your stud diameter and weld process (Drawn Arc or CD). If you have a BOM/takeoff, attach it and we’ll respond with correct ferrule, pricing, and lead time.

Source: Vendor ferrule specifications sheet (licensed for use and adaptation by Eugene Fastener).