Heavy Fabrication, CNC Machining & Assembly Services
First In Service delivers three manufacturing disciplines under one contract from a single 18,000 m² site in Tallinn: heavy fabrication and welding to EN 1090-2 and EN ISO 3834-2, precision CNC machining to ±0.02 mm, and mechanical assembly with FAT testing. Products run up to 35×7×7 m and 160 tonnes, with full material traceability from mill certificate to delivery note.
Sheet metal, heavy fabrication & welding
Eliminate structural weak points with certified precision. Operating across an 18,000 m² workshop area in Tallinn, First In Service delivers heavy fabricated products up to 35×7×7 meters (L×W×H) and 160 tonnes. Quality is rigorously verified through full material traceability and NDT (VT, PT, MT, UT) performed by certified partners. Backed by EN ISO 3834-2 and EN 1090-2 certifications, our highly qualified welders utilise advanced processes including 135/136, TIG, and SAW (up to 100 mm). We specialise in complex materials such as stainless steel, duplex, super duplex, titanium, Inconel, and Hastelloy. Complete surface treatment, from automated shot-blasting to industrial coating systems compliant with extreme anti-corrosion standards (C5-M, NORSOK M-501), ensuring your structures survive the harshest subsea and offshore environments.

Precision CNC machining & turning
Tolerances down to ±0.02 mm, built to perform flawlessly under extreme stress. Our extensive machine park is built for heavy components, long shafts, and complex geometries. We handle turning and milling of parts up to Ø 2,700 mm, 13,000 mm in length, and 4,500 mm in height. Our capabilities are powered by advanced horizontal and vertical CNC lathes, boring mills, and milling centres — including heavy-duty FERMAT boring mills with X-axis travel up to 13,500 mm and Y-axis up to 4,000 mm, vertical turning lathes accommodating up to Ø 2,700 mm, and horizontal lathes supporting workpieces up to 3,250 mm in length.

Complex assemblies & mechanical integration
Plug-and-play delivery. We hand over working systems, not just a box of parts. First In Service delivers complex assemblies and fully FAT-tested modules for demanding industrial applications. From precision bearing installations to fully commissioned units, we assemble, verify, and deliver with full documentation. Our assembly team plans sequences, tooling requirements, and quality checkpoints for efficient, error-free builds. Comprehensive quality documents: we deliver fully transparent, digitised Manufacturing Data Records (MDR), including material certificates (3.1/3.2), NDT reports, dimensional inspection logs, and FAT protocols, ensuring immediate regulatory compliance.

Dedicated capability pages
Heavy Fabrication & Welding
Up to 35×7×7 m and 160 tonnes. EN ISO 3834-2, EN 1090-2, NORSOK M-501 surface treatment.
Full spec →CNC Machining
Ø 2,700 mm, length 13,000 mm, tolerances ±0.02 mm. FERMAT boring mills, VTL, turning centres.
Full spec →Mechanical Assembly & FAT
Mechanical, electrical, and hydraulic assembly with FAT testing and full MDR documentation.
Full spec →Bring us your toughest tolerances.
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