Key Features:
Guide pins possess several key features that ensure precise alignment and durability in demanding applications such as press tools and injection molds:
High Precision and Tight Tolerances: The primary feature is extremely high dimensional accuracy. They often have diameter tolerances in the micrometer (µm) range or as tight as ±0.0001 inches, which ensures a precise fit (either slip or interference fit) with their mating bushings.
Durable Materials: Guide pins are typically made from high-strength and wear-resistant materials like bearing steel (SUJ2), alloy steel (e.g., 20 MnCr5, 4140), or various grades of stainless steel (300 or 400 series).
Hardened Surface: Many guide pins undergo heat treatment processes like case hardening or through-hardening to achieve high surface hardness (e.g., HRC58-62), while maintaining a tough, impact-resistant core.
Superior Surface Finish: The sliding surfaces are precision ground to a fine finish (e.g., 32 microinch Ra or less) to minimize friction and wear when moving within a guide bushing.
Variety of Tip/End Styles: They are available with different end configurations to facilitate assembly, including chamfered ends, radius ends, bullet-nose (rounded) tips, or cone shapes to compensate for initial misalignment.
Specialized Designs: Features can include oil grooves for lubrication retention, heads or shoulders to prevent over-insertion and handle thrust loads, or diamond-shaped tips to provide radial location in only one axis, preventing binding.