The mechanical workshop - the former of Gang Thep Engineering Factory - is an auxiliary unit in Thai Nguyen Iron and Steel Company’s production line of iron and steel. The workshop is responsible for producing spare parts in metallurgical production’s consumable equipment installation.

The factory started production after having completed workshop construction, equipment installation, mobilized staff and workers with total over 400 people.

The factory contributed to the emulation movement of 52 technical innovations, 11 emulation soldiers, and two registration teams to strive for the socialist labor group as the result of striving to follow the call of President Ho Chi Minh "Each person works equal two to repay the gratitude of the South relatives".

President Ho Chi Minh visited Gang Thep for the 3rd time, he visited the mechanical workshop and gave the precious advise to Gang Thep workers that: "In order to make good iron and steel products, the leaders and workers must forge the revolutionary spirit, class standpoint and sense of mastery as tough as iron and steel, especially Party cadres and union members”.

In the early years of a fledgling factory, employees responded to patriotic emulation movements with the determination of "Mastering science and technology to improve Gang Thep factory and establish a career". In 1965, the factory was awarded the Labor Medal of class III by the Government, marking a mature period in the tradition of Iron and Steel Mechanical workers.

During the resistance war against the US, the factory responded to "production and fighting together to protect the production " and contributed to the Communist Party and State's process of resistance against America to save the country. In 1967, the workshop was honored to receive the National Front for the Liberation of South Vietnam flag for the second time.

This was the period of production recovery and condition preparation for production development. On January 28, 1973, the Mechanical Workshop received an order to quickly resume production. In 1975, the workshop focused on manufacturing equipment for Gia Sang Steel Rolling Factory. In 1978, the factory successfully manufactured 840 steel rollers. It was the first unit to successfully manufacture steel rollers for imported products replacement. The factory was honored to be awarded the Labor Medal class II by the State.

In 1983 - 1984 the company was recognized as a unit of decisive victory.

In the period of production and business in the market mechanism, 1988 was a year of great change for the workshop's production and business, which directly affected the development of the company later. In 1989, the mechanical workshop was officially renamed "Gang Thep Mechanical Factory". After getting organizational restructuring, the Company’ development was more and more favorable with the conformity of the business mechanism and policy.
In 1996, the Company was honored to be awarded the First-Class Labor Medal by the government.
In 2000, the Company applied the product quality management system according to international standards ISO: 9001 - 2000.
From January 1st, 2007: The Company changed its name to Gang Thep Engineering Joint Stock Company.

The company has invested in many new equipments, including 2-line R5,25M continuous casting line and LF 20T refining furnace.

The company has invested in a new "high-quality batch detail casting line", a line for casting high-quality billet products for steel rolling mills.

New investment in 04 pairs of medium frequency furnaces of 20 tons/batch in order to improve production output. In 2020, steel billet output has been reached over 120,000 tons/year.
New investment in CNC lathe system, CNC mill machine and CNC boring machine.
New investment in a production line of 100,000 tons of rolled steel per year and a system of sample processing equipment and quality testing of rolled steel according to ISO/IEC 17025:2017.