Architectural industrial bellows expansion pipe

SJM’s leading technology is not miraculously created overnight, but rather developed through a commitment to challenges and new technology development.

Leading the global bellows market with the most expertise in Korea and the best technology in the world––a No. 1 company worthy of its title!

Sungjin Machinery was established in 1975, changed its name to SJM in 1996, and was listed on KOSPI in 1997.

In the 1990s, SJM established local subsidiaries in Malaysia, the Republic of South Africa, and Germany, and in the 2000s, it established local subsidiaries in the R&D center in Ansan City as well as in the United States, China, Mexico, Japan and Morocco.

SJM is leading in the expansion joint market as it actively continues to expand globally.

Currently, SJM’s technology can be seen in Nuri, the space rocket in space, as well as in large vessels traveling across the Pacific Ocean.
SJM’s technology is also widely used in people's everyday lives and in high-tech cities.


SJM. A name everybody knows in the expansion joint industry.
A name that contains the blood, sweat, and tears of 50 years of history

With Korea’s first bellows localization technology as its basis, SJM manufactures expansion joints with its own technology to provide vehicles, architecture, plants, shipbuilding and marine engineering, defense technology, and new mobility to the world

SJM’s industrial bellows technology applies to the fields of vehicles, marine shipbuilding, power plants, petrochemicals, HVAC, steel, water and sewerage, and the defense industry, and the joint substation is not only used in Korea but also exported to global companies such as Fuji, Hitachi and Mitsubishi.

Cryogenic bellows in the shipbuilding and marine engineering field has type authentication for major global companies and it currently occupies about 80% of the global market, which makes it trusted as the No.1 global product.
Construction bellows technology applies to the fields of pumps, air conditioning, sanitation, earthquake resistance, and fire extinguishing. Bellows, slip joints, multi-joints and injection joints are especially used in high-rise apartments, public buildings, and in the high-tech field of semiconductor factories that use a lot of district heating.

In addition, SJM continues to challenge itself in the fields of electric vehicles, hydrogen vehicles, space aviation, high-speed transportation systems, and nuclear fusion power generation with its new mobility and high-tech bellows technology.

The key to maintaining the best quality that surpasses the global market lies in thorough testing.
SJM’s research activities are developing proprietary technologies that continually surprise the global market.

Unrivaled experience and skills proven by 50 years of history!

No.1 quality and reliability recognized by the global bellows market!
As a company with 50 years of experience and goals to reach 100 years, SJM wants to share its technologies with you