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  • Company Name : Youngjin Precision Industrial Co., Ltd.
  • CEO : Choi, Soonmuk
  • Type of business : Manufacturing new automotive power transfer unit
  • Business contents : Manufacturing, researching & developing of automotive parts(Synchronizer ring, double cone, piston bush)
  • Form of company : Middle small sized company
  • Established dated : 1998. May. 8th
  • Number of Employee : 82 (2018)
  • Sales turnover : KRW 61,575,100,000 (2018)
  • Capital : KRW 900,000,000 (2018)
  • Business Profit : KRW 2,319,430,000 (2018)
  • Representative Tel. +82-31-434-3980
  • Web site :
  • Address : #321, 91, Mayu-ro 132beon-gil, Siheung-si, Gyeonggi-do, Republic of Korea

Information from :

Youngjin Precision Logo

Company History
According to the website :
(Copy + Paste)
and some missing information translated from

1998.05 Youngjin Precision Industrial Co.,LTD Established (Gajadong, Incheon)
2001.03 R&D Center Established in Head Office
2002.07 Designated as Tier 1 of Hyundai-Kia and GM-Deawoo Motors
2003.01 Certitied QS9000 & ISO 9002 by K. F. Q
2003.05 Relocated Head Quarter (Sihwa industrial zone)
2004.04 Certified as a material specialist company by Industry and Energy Dept of Gov of South Korea
2004.06 Qingdao Plant established in China(Cheungdo Youngjin Corp)
2004.08 Certified as a high potential export company by Small Business Administration of South Korea
2004.12 New R&D Center established in Songdo Technology Park, Inchoen, Korea
2005.07 Certified “INNO-BIZ” & “Superior Technology Company”
2005.08 Certified TS-16949
2005.11 Certified ISO14001
2006.03 Awarded “Best Corporate Tax” Corporate Recognition(National Tax Service)
2006.12 Young Jin Precision Industry Co,. Qingdao, China acquired Taeksan Award (Pingdu 7th)
2007.11 Awarded “US$ 20,000,000 for Export Award” by Ministry of Commerce
2011.04 Certified “Venture Business Company”
2011.11 Awarded “US$ 30,000,000 for Export Award” by Ministry of Commerce
2013. 11. 30 OHSAS 18001 Safety & Health Management System Certification
2016. 04. 30 Construction of new head office and second research center in Songdo International City
2017. 09. 12 Approved to use the head office and the 2nd institute in Songdo International City

Youngjin Precision Products:

High Strengh Bras Material


(1) Features
In order to improve the base material (brass)’s general properties, such as the strength, toughness, abrasion resistance and friction coefficient, trace amounts of alloying elements were added and attributed a dramatic enhancements on above properties. For the alloy design and manufacturing purposes, various fine strengthening compounds were uniformly distributed in the matrix.

(2) Strength
Change of alloy design and manufacturing allowed improvements in various mechanical properties and lowered costs. It forms a robustness and stable matrix that has excellent abrasion resistance and hardness.

(3) Applied ITEM


(1) Features
Similar to KMS-2E, it also has the base material as brass. With addition of certain alloying elements and through proprietary manufacturing process, heterogeneous structure is formed with uniform distribution of alloying elements in both α and β matrix.

(2) Strength

It has excellent processability and thermal conductivity.

(3) Applied ITEM



(1) Feature
KMF is based on general brass material with a small amount of alloying element, which allows α particle to precipitate in β-phase matrix’s grain boundary. It makes this material very suitable for making structural parts that receives heavy loads or severe temperature changes (-200℃~200℃).

(2) Strength
KMS-2E of above material has excellent abrasion resistance in moist environment but low in dry environment. In contrast, KMF material has the most excellent abrasion resistance in dry environment.

(3) Motivation
Current automobile industry is in the trend of designing higher RPM engines with smaller powertrain. Yet, with current Steel Shift Fork, it is difficult to control the torque changes, vibration and noise. Thus, we developed this new material, KMF, which significantly improve on the controls.

(4) Applied ITEM
Shift Fork

Synchronizer Ring

Manual Transmission Synchronizer Ring

What is Synchronizer Ring?

Synchronizer ring is mounted in the car’s manual transmission. In order to distribute appropriate power according to vehicle speed, each gear stage has different gear ratio composed of different gears. The gears of each stage have different sizes with a different number of teeth, which allow the gears at each stage to rotate at different speed even driving the vehicle at a constant speed. To create the optimal driving condition, two different gears with different gear ratios have to connect to each other, and this is defined as gearshift. If there is a manual transmission without synchronizer ring, gearshift can only be performed at a certain speed ratio (speed) that makes two different gears to combine. (eg. gearshift to 2nd gear at 20km, 3rd gear at 40km and so). In order to remove this discomfort, synchronizer ring is developed and it brings two different gears with different RPM to have the same RPM when the gear is being shifted. With this help of synchronizer ring, automobiles nowadays can easily perform a gearshift at any given speed ratio.


Outline of Piston Bush

Functionality of Piston Bush

Currently, the demand for parts with good durability beyond traditional materials has been a big issue for world’s leading automotive companies including Hyundai and Kia Motors. The importance of the durability of a piston, the most essential part of the engine, has been highlighted in today’s emerging technology. Many of the automobile companies have invested in the development of aluminum alloy that may overcome the stress and heat that generated by the friction of piston and piston pin, but most of them failed to meet the requirements. In response to this problem, piston bush is substituted as an alternative to support the piston pin and at the same time, satisfying its suspension and contraction requirements. Piston bush’s material, KM401, is a strengthened material using high-strength brass that can buffer the extreme temperature as well as the vibration and there enhance the smooth operation of piston and piston pin.


Main Role of SHIFT FORK

SHIFT FORK Main Role of SHIFT FORK During gear shift (1st ~ 5th gear and R gear) in the manual transmission, a shift fork, a part that is fixed at the shift rail, goes into synchronizer sleeve, activates the sleeve and moves the synchronizer ring.

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