History of Brush Seal Development

In the mid-1980s, the United Kingdom, the United States, Germany, and the former Soviet Union all invested substantial human and financial resources into the development of sealing technologies. Notably, the United States designated the research and development of brush seals as one of its "Key Defense Technologies for the Year 2000," while simultaneously classifying it as a high-tech technology prohibited from export to China.

Conventional, standard-model brush seals suffer from issues such as bristle stiffening and hysteresis effects, which exacerbate wear on both the bristles and the mating surface (runner) and lead to increased seal leakage rates. Subsequently, a "low-hysteresis" brush ring design featuring a grooved backing plate emerged; this innovation effectively reduced contact pressure at the bristle-to-runner interface, mitigated the effects of bristle stiffening and hysteresis, and enhanced both sealing performance and durability. Furthermore, advanced high-performance brush seals-incorporating low-hysteresis designs, significantly increased bristle diameters, and flow-shielding plates-can achieve a single-stage operating pressure differential of up to 0.7 MPa, thereby surpassing standard dual-stage configurations in terms of sealing effectiveness, cost-efficiency, and overall quality.