Gia Binh Expansion & SOTEK MACH
Initiated construction of a 53,000 m² high-tech electrical equipment facility in Gia Binh Industrial Park. Established SOTEK MACH Mechanical JSC with a 4,800 m² specialized tank fabrication plant in Dai Dong.
Enterprise Profile
Engineering B2B Power Grid Reliability Since 2008
Established in 2008 under our predecessor Hanoi Transformer Manufacturing JSC (HBT Vietnam), SOTEK Group has grown over 15+ years into a premier B2B distribution transformer manufacturer in Southeast Asia. We specialize in high-efficiency oil-immersed distribution transformers, cast resin dry-type transformers, compartment padmount transformers, and compact kiosk substations.
Operating from our 18,500 m² manufacturing plant in Tien Son Industrial Park, Bac Ninh, Vietnam, SOTEK combines advanced automated layer winding machinery, high-precision laser CRGO silicon core slitting, and automated vacuum resin casting chambers to deliver grid equipment built for 30+ years of maintenance-free service.
"Through strict alignment with IEC 60076 and IEEE C57 standards, SOTEK has successfully delivered thousands of utility-grade transformers to major power grids worldwide, including EVN regional utilities in Vietnam and Aboitiz Power in the Philippines."
Corporate Journey
Key Milestones & Global Expansion
Over 15 years of continuous industrial scaling, international quality certification, and strategic utility grid partnerships across global markets.
Infrastructure Capital Investments
Formed SOTEK LAND Investment JSC and completed a 26,000 m² manufacturing plant in Thuan Thanh 2 Industrial Park, Bac Ninh, accelerating large-capacity transformer production lines.
Global Export & Corporate Rebrand
Established SOTEK Group Corporation and international trade divisions. Successfully launched the SOTEK TRAN export line, completing premier shipments to power utility partners in Australia.
Regional Grid Integrations
Approved as official grid vendor for EVN HCMC (Ho Chi Minh City Power Corp). Expanded international export supply contracts into cross-border utility infrastructure in Laos and Cambodia.
Philippines Grid Certification
Secured approved vendor status with EVN SPC (Southern Power Corp) and exported first major batch of IEC/IEEE compliant distribution transformers to utility buyers in the Philippines.
Foundation of Hanoi Transformer
Founded on March 27, 2008 as Hanoi Transformer Manufacturing JSC (HBT Vietnam), beginning a dedicated legacy of precision electrical core and coil engineering.
Operational Rigor & QA
8-Step Precision Manufacturing Process
Every SOTEK transformer undergoes a strictly controlled, ISO 9001 quality-managed workflow designed to ensure maximum short-circuit strength and zero partial discharge.
01
Laser CRGO Slitting
High-precision automated longitudinal slitting of premium cold-rolled grain-oriented steel laminations to eliminate edge burrs and minimize no-load losses.
02
Automatic Winding
Computerized tension-controlled layer winding for HV/LV copper coils, guaranteeing superior dielectric strength and high mechanical short-circuit resistance.
03
Corrugated Tank Welding
Automated corrugated fin folding, robotic seam welding, and pressure leak testing for total liquid containment and optimal heat dissipation.
04
Step-Lap Core Grafting
Precision 45-degree mitered step-lap stacking in a temperature and dust-controlled environment to minimize magnetizing current and operational noise.
05
Foil Winding Technology
High-purity copper foil winding for secondary coils to eliminate axial short-circuit forces and enhance cooling performance under heavy thermal loads.
06
High Vacuum Drying
Thermal vacuum extraction removes all microscopic moisture from solid paper insulation prior to degassed mineral oil or ester fluid impregnation.
07
Hermetic Final Assembly
Insertion of active core-coil assembly into sealed tanks, followed by hot oil vacuum filling, DETC/OLTC installation, and bushing terminal alignment.
08
FAT Routine Testing
100% routine battery testing (turns ratio, insulation resistance, winding resistance, dielectric loss, impulse withstand) in our VILAS 1183 certified lab.
Verified Compliance
Quality System Accreditations
SOTEK operations strictly conform to international quality, environmental, and safety management standards validated by independent auditing bodies.
ISO 9001:2015
Quality Management System (QMS)
Certified by TÜV NORD / QUACERT for end-to-end electrical design, material traceability, and assembly management.
ISO 14001:2015
Environmental Management System
Rigorous controls over waste management, oil filtration containment, and eco-friendly manufacturing protocols.
ISO 45001:2018
Occupational Health & Safety
Ensuring high-level plant safety standards across automatic winding halls, high-voltage test bays, and fabrication areas.
ISO/IEC 17025:2017
VILAS 1183 Accredited Testing Lab
In-house laboratory accredited for international routine and type testing validation prior to export delivery.
KEMA & ASTA Certified
Type-Tested Short Circuit Reports
Full type-test validation for short-circuit withstand performance, lightning impulse withstand, and temperature rise.
EVN Grid Approved
Certified National Utility Supplier
Qualified vendor for all five EVN regional utilities: EVNNPC, EVNCPC, EVNSPC, EVNHANOI, and EVNHCMC.
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