graphite insert

例句：

1. 1. The graphite inserts in the machine are designed to improve its efficiency.
   机器中的石墨插入物旨在提高其效率。
2. 2. The graphite inserts are made from high-quality graphite material.
   这些石墨插入物由高质量的石墨材料制成。
3. 3. The graphite inserts are used to reduce friction and improve performance.
   石墨插入物用于减少摩擦并提高性能。