Seohan Group

Great Challenge & Innovation!

R&D

SEOHAN
Great Challenge & Innovation
The Seohan Engineering Research Institute is continuously researching and developing chassis parts,
the most essential component for moving cars, and drive modularizations and
eco-friendly products that will lead the future automotive industry.

Performance and History

2025
  • Selected for the World Class+ Project support program　　　　　　　　　　　　　　Development of a four‑wheel independent‑drive electrification module for future mobility (Ministry of Trade, Industry and Energy)
2024
  • Winner of the IR52 Jang Young‑Sil Award (High‑strength constant-velocity joint for electric vehicles with carbon‑reduction technology)
  • Prime Minister’s Commendation for Industrial Technology Promotion　　　　 (New Technology Commercialization category)
2023
  • Received NET (New Excellent Technology) certification (Cast Iron H/Disc)
  • Certified as a Specialized Company in Materials, Parts, and Equipment
2022
  • Received the Technology 5-Star 5★ rating (HMC)
  • Received the certification as a company specializing in materials & components
2021
  • Received the Technology 5-Star 5★ rating (HMC)
  • Received the certification as a company with Excellent job invention compensation
  • Developed Damper Fork
2020
  • Received the Technology 5-Star 5★ rating (HMC)
2017
  • Received the Technology 5-Star 5★ rating (HMC)
  • Excellent Product Development Partner Award (HMC)
  • IR52 Jang Youngsil Award (Hybrid Disc)
2016
  • Developed Aluminum Knuckle & Carrier
2013
  • Lightweight Hybrid Disc New Technology Certification (NET)
2012
  • Research institute moved (Dongtan)
  • Korea’s first LSJ that minimizes lateral vibration developed
2007
  • CJ with excellent rotational balance developed domestically
2001
  • Established Seohan Engineering Research Institute (Jincheon)

Corporate Organization

  • Research Facilities
    Office Building 3,147㎡ / Testing Center 3,150㎡ / Amenities 3,123㎡
  • Researchers
  • Research Equipment

Research & Development Areas

Driveline & Chassis
Joints for Halfshaft
Shafts for Halfshaft
Joints for Propeller shaft
New Joints for Halfshaft
Axle Ass’y
Brake Disc
Driveline & Chassis
Joints for Halfshaft
  • Fixed Joint

    • BJ

      A standard wheel-side joint engineered for superior stability and durability by applying angular contact between the balls and the inner/outer track.

    • EUJ

      A compact, 8-ball specification of the UBJ that enhances efficiency by reducing heat generation and minimizing torque loss.

    • BJc

      Engineered to be more compact and lightweight than the BJ specification, while securing identical strength and durability performance.

    • HBJ

      This joint features a counter track to achieve a 52° maximum articulation angle, enhancing efficiency by lowering heat generation and minimizing torque loss.

    • UBJ

      This joint incorporates an undercut track to realize a maximum articulation angle of 50° and superior strength at high angles.

    • SJ

      A dedicated rear-wheel joint incorporating a counter track, which boosts efficiency by reducing heat generation and minimizing torque loss.

    • SUJ

      Features a symmetrical undercut track to deliver a maximum articulation angle of 50° along with superior strength and durability at high angles.

    • FCJ

      A dedicated rear-wheel joint featuring a cross-groove track that reduces heat generation, torque loss, and backlash.

    • EBJ

      A compact, 8-ball specification of the BJ that enhances efficiency by reducing heat generation and minimizing torque loss.

  • Plunging Joint

    • TJ

      A standard roller-type joint providing exceptional stability and durability.

    • TJC

      Engineered to be more compact and lightweight than the TJ specification, while securing identical strength and durability performance.

    • LSJ

      A roller kit type joint delivering superior low-vibration and NVH (GAF and PR) performance.

    • HLSJ

      Features an improved articulation angle and sealing performance over the LSJ model.

    • DOJ

      A ball-type joint equipped with a double offset straight track and a longer stroke than the TJ.

    • EDOJ

      A compact, 8-ball specification of the DOJ that enhances efficiency by reducing heat generation and minimizing torque loss.

    • CJ

      A joint incorporating a cross-groove track for superior NVH performance and minimized backlash.

    • ECJ

      A compact, 8-ball specification of the CJ that enhances efficiency by reducing heat generation and minimizing torque loss.

Shafts for Halfshaft
  • Hollow Shaft

    • WTS (Friction Welding Tubular Shaft)

      30% weight reduction compared to solid shaft, Improvement of NVH performance, High torsional stiffness

    • MTS (Monoblock Tubular Shaft)

      40% weight reduction compared to solid shaft, Improvement of NVH performance, High torsional stiffness

Joints for Propeller shaft
  • Joints for Propeller shaft

    • Disc CJ (Cross groove Joint)

      • Maximum articulation angle: 4°
      • Superior NVH performance
      • Lightweight & compact design

    • Disc BJ (Birfield Joint)

      • Maximum articulation angle: 7°
      • Suitable for high-speed rotation and high-angle vehicle models
      • Compact design applying a J-shaped boot

    • Monoblock CJ (Cross groove Joint)

      • Maximum articulation angle: 4°
      • Superior NVH performance
      • Cost-effective and weight-reduced specification

    • Flange BJ (Birfield Joint)

      • 4-hole flange specification
      • Suitable for high-speed rotation and high-angle vehicle models
      • Compact design applying a J-shaped boot

    • Flange CJ (Cross groove Joint)

      • 3-hole flange specification
      • Optimized for vehicle assembly process
      • Lightweight design compared to the disc specification

    • Disc HBJ (High efficiency Birfield Joint)

      • 8-ball compact design
      • High-torque and high-efficiency specification
      • Superior durability from low heat generation

    • DCJ (Direct Connecting Joint)

      • 8-ball monoblock design
      • Excellent backlash performance
      • Spline structure for direct assembly to the vehicle

    • Disc PSJ (P/Shaft Symmetric offset Joint)

      • 8-ball compact design
      • Features a symmetrical track structure
      • Superior durability from low heat generation
New Joints for Halfshaft
  • New Joints for Halfshaft

    • IDA (Integrated Drive)

      A next-generation hub bearing that integrates the Hub and Halfshaft. Lightweight with high lateral rigidity. IDA Composition: Can be assembled by combining IDA with various joints like ECJ, FCJ, and EDOJ.

    • BSJ (Ball Spline Joint)

      Integrates a ball spline design into the inner race of the lightweight, 8-ball SJ / FCJ joint. Maximum articulation angle of 32° and a plunging length of 62mm.

Axle Ass’y
  • Aluminum Knuckle & Carrier

    Casting methods (high pressure, counter pressure, low pressure)

    Securing product competitiveness through diversification of manufacturing processes

  • Disc Machining & Surface Treatment

    New machining process for braking surfaces

    New surface treatment process

  • Modularization

    Axle & Halfshaft, Axle & Brake Complete, Integrated Axle

    Improved system performance

    New system structure

Brake Disc
  • All-Aluminum Disc Development

    Achieves 50% weight reduction through all-aluminum construction, adapting to the future vehicle environment.

  • Aluminum Hybrid Disc Development

    Realizes improved fuel efficiency and ride comfort by applying aluminum to the mounting area for weight reduction.

  • Cast Iron Hybrid Disc Development

    Responds to the demands of EV platforms by improving strength and reducing weight through material changes.

  • Nitrided Disc Development for Rust Prevention

    Achieves improved disc lifespan and functional enhancements through the development of a surface-nitrided disc.

Achievements of Research

Industrial Property Rights
  • 94
    Patents registered in Korea
  • 10
    Patents registered internationally
  • 37
    Domestic and international applications
  • 4
    Designs