The nomenclature specifies the tool's exact structural dimensions and insert compatibility:
C25: Indicates a 25 mm straight shank diameter for mounting into side-lock holders or collet chucks.
3D: Represents the drilling depth-to-diameter ratio, meaning the tool can drill up to 3 times its diameter deep (3 × 17.5 mm = 52.5 mm usable depth).
17.5: The exact cutting or hole diameter of 17.5 mm.
56: The maximum effective flute/drilling length of 56 mm.
SP06: Dictates that the drill uses SPGT060204 (or SPMG060204) square carbide inserts.
Technical Design & Features
Insert Configuration: Uses 2 indexable inserts per tool—one central insert to cut the core and one peripheral insert to clean the outer diameter.
Internal Cooling: Features dual thru-coolant holes running through the body to deliver high-pressure fluid directly to the cutting edges for chip evacuation and heat reduction.
Asymmetrical Geometry: Designed with offset cutting edges to balance radial forces, eliminate drift, and achieve high-precision tolerances.
Material Construction: Made of high-grade alloy steel (typically 42CrMo) hardened to HRC50-53 for anti-vibration and structural rigidity.