ER25 DIN 6499 (DIN ISO 15488) collets with coolant sealing are designed for tool clamping in CNC machining applications where coolant control, system stability, and process repeatability are critical. The ER25 range, with a clamping capacity from 3.5 to 16 mm, provides an excellent balance between clamping strength and precision, making it suitable for medium to large component machining.

The operating principle is based on the standard ER geometry, ensuring uniform elastic clamping along the entire tool shank and consistent force distribution, reducing transmission play between tool and spindle. Neoprene inserts integrated into the collet slots ensure effective coolant sealing: positioned within the 30° taper, they isolate and direct the coolant exclusively through tools with internal channels, preventing leakage and improving lubrication and cooling efficiency up to 25 bar.

From a metrological perspective, ER25 sealed collets ensure high concentricity and clamping stability, reducing form errors and geometric deviations. Increased rigidity minimizes vibrations, improving surface finish and extending tool life, particularly in high-speed and heavy machining operations.

These collets are suitable for milling, drilling, boring, and finishing operations on metallic materials where controlled internal coolant flow is essential for chip evacuation, thermal control, and process continuity. They are widely used in automotive, precision engineering, mold making, and CNC production environments requiring high accuracy and reliability.