Guide sleeve, straight sleeve

Both straight guide bushings and support guide bushings serve the same function; the only difference lies in their standards: support guide bushings conform to HASCO standards, while straight guide bushings adhere to DME U.S. standards and Hong Kong Longji standards. Depending on customer requirements, guide bushings are commonly used for drilling and boring. Those used for drilling are called drill bushings, whereas those for boring are referred to as tool‑holder guide bushings. Their purpose is to ensure that the drill bit or tool holder remains aligned during cutting, thereby enhancing both the dimensional accuracy and positional accuracy of the machined hole. They are widely employed in industrial enterprises.

The “guide bush” in a mold, also known as a “side pin,” serves to provide guidance. The guiding mechanism ensures that the upper and lower dies align correctly. The most common type is the straight guide bush–guide post assembly. Additionally, large molds may be equipped with guide plates, while miniature stamping dies may use guide tubes, which perform the same function as the guide post–guide bush assembly.

Driven by rapid economic growth and guided by sound national industrial policies—particularly through the preferential VAT policy of collection first, refund later enjoyed by key enterprises—the Chinese die‑casting mold industry has steadily advanced. The sector’s development is characterized by substantial progress in medium- and high‑end molds and standard components that are large, precision‑engineered, complex, and designed for long service life. The share of plastic molds and die‑casting molds has increased, the number of specialized mold manufacturers has grown, and their capabilities have improved markedly. Meanwhile, foreign‑invested, joint‑venture, and privately owned enterprises have expanded rapidly, gradually becoming the mainstay of the industry.