Kemmler ER Collet Chucks DIN 6499 with SK Taper

Available Sizes and Part Numbers

Purpose and Application

Kemmler ER system collet chucks (DIN 6499 and ISO 15488 standards) are designed for installation on CNC milling machines and machining centers with SK spindles according to ISO 7388-1 (formerly DIN 69871). They serve for reliable clamping of end mills, drills, boring heads, and other cutting tools with cylindrical shanks using interchangeable ER collets. The tooling is a universal standard for finishing, semi-finishing, and high-speed metalworking operations.

Design and Features

Tool clamping is carried out by tightening the clamping nut, which compresses the taper collet inside the chuck. All chucks in the series are supplied complete with a balanced clamping nut, minimizing vibration loads at high RPMs. Radial runout of the inner collet taper does not exceed ≤ 3 µm. Factory dynamic balancing is performed to class G 2.5 at 25,000 rpm. The design includes a special bore for an RFID chip used in automated tool management systems.

Compatibility

Chucks are intended for machine spindles with SK 30, SK 40, and SK 50 tapers (ISO 7388-1 / DIN 69871). Compatible with ER system collets according to ISO 15488 B (DIN 6499 B) standards in sizes ER 16, ER 20, ER 25, ER 32, and ER 40. For mounting in the spindle, pull studs according to ISO 7388-3 (formerly DIN 69872) with appropriate THID thread (M10, M12, M16) are used.

Selection Parameters

Chuck selection is made based on the spindle taper size (SK 30, SK 40, SK 50) and ER collet size:

• ER 16 (426E): shank clamping diameter 1–10 mm;
• ER 20 (428E): shank clamping diameter 2–13 mm;
• ER 25 (430E): shank clamping diameter 2–16 mm;
• ER 32 (470E): shank clamping diameter 2–20 mm;
• ER 40 (472E): shank clamping diameter 3–26 mm.

By coolant supply type, chucks are available in Form AD (central coolant supply) and Form AD/B (universal execution with optional coolant supply through the flange). Extended modifications with LPR projection up to 200 mm are also manufactured for deep cavity machining.

Key Advantages

• High Machining Accuracy: radial runout ≤ 3 µm guarantees minimal dimensional deviation and extends cutting edge service life.
• High-Speed Balancing: class G 2.5 at 25,000 rpm reduces vibrations and protects spindle bearings from wear.
• Universal Clamping Range: support for collets from ER 16 to ER 40 allows covering shank diameters from 1 to 26 mm.
• Complete with Balanced Nut: the chuck is delivered ready for use with a precision nut included.
• Execution Variabity: availability of Form AD and Form AD/B versions, as well as extended modifications (LPR 50–200 mm) for any production tasks.