SOI Automotive Manufacturing sets the global standard for engineered excellence — from stamped steel to final assembly, every component reflects our uncompromising legacy.
38+
Years of Operation
2.4M
Units Produced
47
Global Markets
Who We Are
Engineering the Future of Mobility
Founded in 1987 in the heart of South Holland, SOI has grown from a precision machining workshop into one of Europe's most respected full-cycle automotive manufacturers. Our Haarlem facility spans over 140,000 m² of advanced production space.
From chassis architecture and powertrain integration to final quality validation, every stage of our process is executed with ISO-certified precision and a relentless commitment to innovation.
What We Offer
Core Capabilities
01
⚙️
Precision Machining
CNC-controlled multi-axis machining centers operating to tolerances of ±0.002mm across all structural and powertrain components.
02
🔩
Body & Frame Assembly
Robotic MIG/TIG welding lines capable of processing 240 body shells per shift with full structural integrity verification.
03
🏭
Stamping & Forming
High-tonnage stamping presses from 800T to 4,000T delivering complex panel geometries with consistent surface quality.
04
🎨
Surface Treatment
State-of-the-art electrophoretic coating and automated paint booths achieving Class-A surface finishes on all body panels.
05
🔋
EV Drivetrain Integration
Dedicated EV assembly cells for high-voltage battery modules, inverter stacks, and e-axle units for next-generation vehicles.
06
✅
Quality Assurance
Inline CMM measurement, vision systems, and end-of-line functional testing ensuring zero-defect delivery across all product lines.
Connect with our engineering and business development team to explore what precision manufacturing can do for your next project.
Home / About Us
Our Legacy
Our Mission
Drive Progress Through Craft
SOI exists to manufacture vehicles and components of extraordinary quality — combining Dutch engineering precision with global scale manufacturing, while upholding environmental responsibility and human-centered values in everything we build.
Our Vision
Lead the Electric Era
By 2030, SOI aims to be a carbon-neutral manufacturer with 60% of our production capacity dedicated to fully electric vehicle platforms. We believe the future of mobility is earned through innovation, not inherited through legacy alone.
Our History
Built Decade by Decade
1987
Foundation in Haarlem
SOI was established as a precision machining subcontractor serving Dutch automotive OEMs. A 3,000 m² workshop and a team of 24 engineers marked our humble beginning in South Holland.
1994
First Major OEM Contract
Secured a 5-year supply agreement with a major European vehicle manufacturer for stamped structural components — our first entry into high-volume production and the turning point in our growth trajectory.
2001
ISO 9001 Certification & Expansion
Achieved ISO 9001 certification and expanded the Haarlem facility to over 40,000 m². Launched our Body-in-White division and introduced fully automated robotic welding cells.
2008
Global Markets Penetration
Opened export partnerships across 18 countries. Established regional logistics hubs in Germany, France, and the UK to serve our growing European and international client base.
2016
EV Strategy Launch
Inaugurated our Electric Mobility Division — a dedicated production wing for high-voltage battery enclosures and e-axle assemblies, positioning SOI at the forefront of the industry's electrification wave.
2024
Industry 4.0 Transformation
Completed full digital integration across all production lines with AI-driven quality inspection, real-time telemetry, and a full MES rollout. SOI now operates as one of the Netherlands' most advanced smart factories.
What Drives Us
Our Core Values
🔧 Precision First
Every specification is a commitment. We hold ourselves to tolerances that others consider impossible — because our clients' performance depends on our exactness.
🌍 Sustainable by Design
From energy-efficient press operations to closed-loop water systems, sustainability is not a policy — it is embedded in our engineering choices at every level.
🤝 Partnership Over Transaction
We build long-term relationships with our OEM and Tier 1 partners. Our engineers are embedded in client programs from concept through production launch.
⚡ Innovation Always
R&D investment represents 6.2% of our annual revenue. We continuously challenge our own methods — if a better process exists, we find it and implement it.
The People Behind SOI
Leadership Team
Hendrik van Dijk
Chief Executive Officer
Inge Vermeer
Chief Operations Officer
Pieter Hartman
Chief Technology Officer
Maaike Bos
Chief Financial Officer
Home / Manufacturing
Our Process
How We Work
From Raw Material to Road-Ready
Our manufacturing process is a precisely choreographed sequence of stages — each validated, measured, and optimized to deliver components and assemblies that meet the most demanding automotive standards in the world.
01
Material Intake & QA
Incoming steel coils, aluminium billet, and polymer compounds are inspected with spectrometric analysis and certified to EN/ISO material standards before entering production.
02
Stamping & Forming
Transfer press lines and tandem press systems shape flat blanks into complex three-dimensional parts with sub-millimetre repeatability across millions of cycles.
03
Welding & Joining
Automated robotic MIG, TIG, and laser welding cells construct sub-assemblies and body structures, followed by full seam integrity verification via destructive and non-destructive testing.
04
Surface Finishing
Parts progress through alkaline cleaning, phosphating, cathodic E-coat immersion, primer application, and top-coat painting in our full-line paint shop.
05
Machining & Sub-Assembly
CNC machining centres produce precision-finished interfaces; sub-assembly lines integrate bearings, seals, fasteners, and wiring harnesses to build complete modules.
06
Final Assembly
Main assembly lines integrate all sub-systems using torque-controlled tooling and in-process verification — every fastener, every joint confirmed by our MES system.
07
End-of-Line Testing
Rolling road, wheel alignment, headlight aim, brake efficiency, water ingress, and full electrical functional tests validate every vehicle before it leaves the line.
08
Logistics & Dispatch
Just-in-sequence delivery to OEM plants and Tier 1 customers via our dedicated logistics network — on time, every time, with full traceability documentation.
Production Facilities
Inside Our Haarlem Plant
Robotic Welding
Final Assembly
CNC Machining
Quality Control
Technical Proficiency
Manufacturing Excellence Index
Dimensional Accuracy (CMM)98.7%
First-Time Quality (FTQ)99.2%
On-Time Delivery Rate99.6%
Overall Equipment Effectiveness (OEE)87%
Automation Coverage76%
Carbon Efficiency vs 2015 Baseline62% Reduction
Home / Products & Services
Products & Services
Structural
Floor Pan Assembly
Hot-stamped ultra-high-strength steel (UHSS) floor pan structures engineered for maximum crash energy absorption and torsional stiffness.
UHSS 1500 MPaHot StampedOEM-Grade
Powertrain
Engine Cradle
Precision-welded aluminium and steel engine cradles optimised for NVH isolation, structural integrity, and ease of powertrain installation.
Al / Steel HybridRobotic WeldedNVH Optimised
Body Panel
Door Skin & Inner
Outer skin and inner reinforcement panel sets stamped from BH180/BH220 steel, hemmed and clinched to Class-A surface standards.
BH220 SteelClass A SurfaceHemmed
Chassis Module
Corner Module Assembly
Fully assembled corner units integrating knuckle, hub bearing, caliper, ABS sensor, and spring-damper for sequenced delivery to assembly lines.
JIS-SequencedFull Functional
Body Module
Trimmed Door Module
Complete door assembly including glass, regulator, mirror, wiring harness, speaker, handles, and seals — installed as a single unit.
Complete SystemHarness Integrated
Interior Module
Cockpit Assembly
Instrument panel carrier, HVAC integration, wiring system, and display module assembled and pre-tested before delivery to the trim line.
Pre-TestedHVAC Ready
EV Platform
Battery Pack Housing
Structural aluminium battery enclosures with integrated cooling channels, IP67 sealed, and designed for high-voltage safety in side and bottom impact events.
IP67 SealedHV SafetyAl Extruded
Drivetrain
E-Axle Assembly
Electric drive axle integrating motor, inverter, and gearbox into a compact, lightweight unit for BEV and PHEV skateboard platforms.
BEV / PHEVIntegrated Inverter
EV Infrastructure
On-Board Charger (OBC)
High-efficiency 11kW and 22kW on-board chargers with CCS and CHAdeMO compatibility, fully integrated with vehicle BMS architecture.
11kW / 22kWCCS Ready
Engineering
Design for Manufacturing
Our DFM team works with clients during early concept phases to optimise designs for manufacturability, cost reduction, and quality targets.
CAD/CAMFEA Simulation
Tooling
Tool & Die Design
In-house design and manufacture of progressive dies, transfer tools, checking fixtures, and assembly jigs with full tryout and qualification.
In-HouseFull Qualification
Quality
PPAP & APQP Support
Full Production Part Approval Process and Advanced Product Quality Planning support, including DFMEA, PFMEA, control plans, and MSA studies.
IATF 16949Level 3 PPAP
Ready to Collaborate?
Request a Quote Today
Home / Contact Us
Get in Touch
SOI Headquarters
📍 Address
Building 1097, Keizersgracht
Apt 189
Haarlem, South Holland
4772 UZ, Netherlands
📞 Phone
+31-3-2212-5342
Mon–Fri, 08:00 – 18:00 CET
✉ Email
info@soi-automotive.nl
General enquiries & partnerships
