In 1973, a contract was signed for construction machinery for the development of the Dzungaria / Beijiang oil fields (including the Karamay Oil Field and other oil fields scattered across the Dzungar / Junggar Basin in northwestern Xinjiang Province). This included machinery such as wheel loaders (for road construction to transport materials to the oil field) and Komatsu pipe layers (for laying pipelines from the oil field to the oil storage facility).

In the 1970s and 80s, many of China's oil fields—including the Liaohe Oil Field, the Dagang Oil Field, and the Shengli Oil Field—were developed. West Japan Trading continued to receive contracts for construction machinery for oil field construction and seamless pipes for oil well drilling.