Xrun Epoxy Supports Successful Commissioning of China’s First Complete‑Domestic‑Set 110 kV Dry‑Type Transformer

In November 2025, China’s first fully‑domestically‑produced 110 kV, 50 MVA large‑capacity dry‑type transformer was successfully put into service at Yuejin Road Substation in Dongli District, Tianjin. It set a new record for the State Grid system for the highest‑voltage and largest‑capacity dry‑type transformer, and marks a historic leap for China’s high‑end electrical insulation materials sector from “following others” to “independent controllability”.

For a long time, core technologies for high‑end electrical epoxy insulation materials were controlled by overseas companies, with products largely relying on imports. “Adopting imported solutions means essentially conducting experiments for others.” This frustration voiced by the project team epitomized the “bottleneck” challenge confronting China’s power‑equipment manufacturing industry. Back in 2022, the State Grid Tianjin Electric Power Company led a nearly‑100‑member project team. Starting with epoxy insulation materials, the team resolved to tackle this tough technical challenge.

As the core insulation‑material supplier for the project, Shanghai Xrun Epoxy worked closely with the project team, participating fully in technical breakthroughs covering formula R&D and casting‑process optimization. It overcame technical hurdles such as lightning impulse resistance and partial discharge control, achieving performance metrics on par with international advanced standards and realizing replacement with “domestic core components”.

On May 8, 2026, People’s Daily ran an in‑depth report on the project, detailing the full process from material research‑and‑development and process testing to standard formulation. The report fully acknowledged the landmark significance of domestic insulation materials in breaking monopolies and achieving independent controllability.