Hilti FX 3-A Cordless Stud Fusion Unit for F-BT Studs

The Hilti FX 3-A is a battery-powered, fully automatic cordless stud fusion unit that supplies the welding energy for the Hilti Cordless Stud Fusion (CSF) system. Hilti describes it as a compact, portable base unit for fusion welding F-BT threaded studs to steel without a power cord, heavy gas cylinders or an angle grinder in the welding step. It is sold on the Hilti UAE site as item 2270477 with a sleeve, and the hand tool, studs, gas can and surface preparation tools are separate system items.

Threaded studs welded to steel for cable tray and pipe supports

The Hilti CSF Technical Manual classifies the process as drawn arc stud welding with shielding gas (process 783 under EN ISO 14555). Application groups listed include welded and modular support for cable trays, welded support for pipe trays, modular support for pipes, individual and multi-disciplinary supports, suspended ceilings, equipment fastening and shipbuilding fastening. The Hilti page names fastening to steel in polluted or corrosive environments up to C5, offshore wind, oil and gas installations, and shipbuilding. The manual lists type approvals from ABS, Bureau Veritas, DNV, ICC-ES and Lloyd's Register.

Technical specifications

How the welding code works

Per the manual, electrical and mechanical process parameters are pre-set from the H-code, and the required code is stamped on top of each stud. The operator selects the code on the one-touch control panel, the FX 3-HT hand tool lifts the stud automatically to the correct distance before the arc is struck, and the unit regulates welding current against voltage to control total energy. Hilti states that the same hand tool serves all studs, with the stud holder changed to match stud diameter. Surface preparation depends on the coating: the manual assigns the FX 3-ST d14 surface tool to mill scale and weldable primer up to 25 micrometres and the FX 3-ST d20 to non-weldable primer, HDG and multi-layer coatings up to 1000 micrometres.

Selection and ordering checks

Confirm the stud range (F-BT-MR M6 to M12 and the imperial sizes in the manual), the steel grade and thickness, the coating system, the design loads from the Hilti manual or PROFIS Modular Support Engineering software, and the welding procedure specification required by your project. Check the Hilti page for the matching hand tool, battery, gas can and surfacing tools, and for site conditions such as wind, which the manual addresses under welding protection. The photograph on this page is the Hilti product image and is labelled FX 3; the specifications above follow the FX 3-A page.

Documents and quotation

For a quotation on the FX 3-A, send Seven Star LLC the exact model, quantity and delivery point in Oman or elsewhere in the GCC. Seven Star LLC is an independent supplier based in Muscat and does not hold any manufacturer status for Hilti. The Hilti Cordless Stud Fusion (CSF) Technical Manual 07/2026 (English, 9.5 MB) is attached as a manufacturer PDF; it covers the whole CSF system, not the FX 3-A alone. Current item numbers, pack sizes and availability should be read from the Hilti product page. Related Hilti items sit in the Material Handling & Lifting Equipment category.