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【SEM 60th Anniversary Series】An International Business Starts with 100 Yuan Drawings
Release time:2018-06-04

Research and Development History of SEM

In 1958, SEM entrepreneurs set up 8 cottages and 5 sheds in a wilderness area. In 1976, business leaders started focusing on wheel loaders. And in 2013, the product line was expanded to wheel loaders, soil compactors, motor graders and track-type tractors. Along the way, SEM came to understood that R & D was the core of enterprise development and would guide the company through challenges to introduce new products and earn more business.

Taking Aim at Market Vacancies

The founders of SEM started the business as a small agricultural tools manufacturing and repair factory. After a period of development, factory director Mr. Wang Guocai noticed a market need for machines. After much market research and customer visits, he decided to develop the highly-demanded wheel loader. Current SEM Chief Engineer Guo Jinhai says, at that time, there was no professional R&D staff at the factory. In 1976, during the planned economy period, only a few enterprises were authorized to produce construction machinery equipment. SEM was not on that list. After a long search in several cities, former director Mr. Wang Guocai eventually purchased wheel loader drawings for 100 Yuan.

With those drawings, a passionate but non-professional team needed only 8 months to begin trial-producing the first JZ425 wheel loaders in May 1977. SEM then embarked on a loader-based technology research and development road. In 1978, the National Ministry of Metallurgy selected the fledgling JZ425. The first batch of 9 wheel loaders was sent to support key national metallurgical departments. In 1983, the ZL25, an upgraded version of the JZ425, participated in the national 500-hour reliability contest in Liuzhou, Guangxi Province for 4 months. The result: SEM ranked No. 1 in attendance, reliability, noise and sealing.


Trial production of the first JZ425 wheel loaders in 1977


JZ425 in work


ZL25 participates in the 500-hour reliability contest in Liuzhou, Guangxi

Professional R&D personnel were scarce in the 70s and 80s. However, the addition of the wheel loader drawings required a need for professional engineers to interpret the drawings and set up a manufacturing base. The founders of SEM again demonstrated their vision by creating a path for talent cultivation. They selected 90 high school graduates and invited famous professors from top scientific research institutes to create SEM’s homegrown scientific and technological personnel, also known as the famous “1984 TV University Students” of SEM. This is the beginning of the relationship between SEM and the Tianjin Engineering Machinery Institute. For the next 20 years, SEM achieved enormous progress in scientific research ability and strength. More and more young people with engineering machinery dreams joined SEM and helped to develop the company’s reputation for durable, quality products. Mr. Wang Shouhang, the national wheel loader technical expert from Tianjin Engineering Machinery Academe, has made great contributions to SEM wheel loader development and research and laid a solid foundation for future product development.


ZL50D developed in 1988

Mr. Guo Jinhai has always been grateful that he was Mr. Wang’s last apprentice. Mr. Wang’s profound knowledge and academic rigor influenced a generation of SEM designers, helping SEM set up its own wheel loader research and development system.

In 1980, SEM and the Tianjin Engineering Machinery Academe jointly developed the first scrap loader grasper. In 1984, they jointly developed the first ZL25A wheel loader, with a single plate lift arm, single rocker arm, horizontal lifting cylinder and automatic leveling bucket design invented domestically.

Mr. Guo Jinhai is also honoring the tradition of cultivating young staff, with many of them already assuming important jobs. Seeing the growth of SEM, Mr. Guo Jinhai firmly believes that “to develop products with an open mind and create a market with innovative ideas is a magic weapon for SEM.”


SEM Forms Product Series

SEM reinvested 120 million Yuan from 1995 to 2000 to implement 5 national-level technology renovation and innovation projects.  It was a slow step into the fast lane for the company. From 1993 to 1999, the entire industry had faced the reality of few product series and technical problems. Cases of rework and repair were occurring daily because of quality issues. Mr. Guo Jinhai, then a technician in the quality inspection department, began disassembling and reassembling almost every hydraulic part to test and compare with the brochures. He also helped prepare the inspection cards for all the wheel loader parts. The process was long and hard, but proved invaluable for later research and development.

In 1998, SEM independently developed the F series models. The external look of the ZL50F adopted the streamlined design, large arc glass and the all-sealed structure. It was the first product upgrading at SEM and F series products such as ZL30F, ZL40F, ZL50F AND ZL60F followed. “In 1998, the F series was featured at the Construction Machinery Exhibition in Beijing,” remembered Mr. Guo Jinhai. “The streamlined appearance design, wide field cab, advanced hydraulic system and excellent performance drew the great attention of the industry, changing what was the ‘thick, heavy, linear’ image of China’s construction industry and becoming the trend in the industry.”

In 1999, Mr. Guo Jinhai entered the SEM Research and Development Institute and quickly advanced to become the core R&D member of SEM. Under his guidance, SEM has completed the continuous improvement of F series, E series, G series wheel loaders, etc.

SEM introduced the soil compactor as a promising new profit growth point in September 2002.  One month later, the company purchased 4 sets of assembly units of German soil compactors for on-site assembly and research, laying a foundation for future soil compactor production.

The customer is everything. SEM has always focused on service, winning a good reputation among users. “A differentiation strategy, including product and service differentiation, is the most important competitive strategy for SEM,” said Mr. Guo Jinhai. “SEM is one of the first to introduce differentiated products to the market. In addition, SEM’s product is very sturdy and durable. And many customers say, in harsh conditions, only SEM products last.”

The advances in R&D enabled SEM to be designated by the former State Economic and Trade Commission to manufacture wheel loaders. The main product series covers wheel loaders and other personalized products to meet various needs. The G and H series SEM wheel loaders, with green design and safety features, have reached a world-class level with advanced electromechanical and hydraulic integration technology.


JZ 425 loader holds logs

In-Depth Integration

In March 2003, SEM began its association with the global industry leader, Caterpillar. SEM became a wholly-owned subsidiary of Caterpillar in 2008. Caterpillar had already established a technology research and development center in Qingdao and had recruited R&D talent from top national engineering universities, injecting new vitality into SEM. Those young talents from the Caterpillar Research and Development Center have become the research and development backbone of Caterpillar and even the entire industry.


Work photo of SEM chief engineer Mr. Guo Jinhai

Mr. Guo Jinhai said SEM benefited from the technology integration with Caterpillar. “As a Caterpillar brand, SEM deeply feels the century-old Caterpillar greatness. The well-developed knowledge, personnel, development process and validation system guarantee the performance, reliability and quality of the products. In the process of technology integration, of course, there was also conflict between rigorous Caterpillar and flexible SEM. But after joining Caterpillar, SEM’s product quality, product series expansion and overall products are obviously improved.”


A series of differentiated products


The SEM product line has grown from the original single wheel loader to soil compactor, motor grader and Track-type tractor four categories. In 2010, the SEM soil compactor enters the market. The machine adopts Cat’s patented pod-type vibration system, improving the life of vibration bearings, extending maintenance intervals and effectively reducing maintenance costs. The SEM motor grader was introduced in 2011. It has the core technology of the Cat motor grader, especially on hydraulic systems and key structural components. In the cab, it maintains the small clearance lever of Cat’s design concept, with proper distance between the human body and the operating device. Even in challenging conditions, the driver will not be too busy in the cab.  

114 years ago, in Stockton, California, Benjamin Holt made history by testing a steam-powered track-type tractor prototype for the first time. In 2012, the SEM Track-type tractor came into the market with the leading hydrostatic technology. For operational ease, the hydrostatic steering does not need to be braked before shifting and can quickly turnaround with load, saving power and fuel and improving work performance.

At the Beijing Construction Machinery Exhibition 2017, SEM introduced the SEM 512 soil compactor and SEM 816 forest Track-type tractor, customized for the needs of overseas work environments. Over the past decade, with Caterpillar’s sustained commitment and R&D vision, SEM’s R&D has taken root in China while also serving the global market. As a strategic utility brand of Caterpillar, SEM will continue to grow. This is the company’s goal and Mr. Guo Jinhai’s expectation.

SEM soil compactor and motor grader on African Ghana site



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