BT tool holder

shrink fitfor machiningfor precision engineering

Product Overview

• High dynamic balance: balanced to G2.5 at 25,000 rpm; balanced to G1.0 at 60,000 rpm
• High precision: extra-long design; tool holder runout ≤0.001 mm; runout accuracy within 0.003 mm at 4×D
• High clamping force: approximately 2× DIN standard
• Corrosion-, wear- and rust-resistant: special surface treatment
• Dimensional accuracy with minimized heat-treatment distortion: fine milling of key groove after heat treatment
• Durability: up to 3,000 clamp cycles when used with Conprofe Shrink-Fit Machine

Working Principle
Clamping is achieved using thermal expansion and contraction. The tool holder is heated with the Shrink-Fit Unit, the cutting tool is inserted while the bore is expanded, and the holder contracts on cooling to clamp the tool directly. No mechanical connecting components (collets, nuts) are required, making the system suitable for high-speed machining demanding dynamic balance, runout accuracy and clamping rigidity.

Application Cases
Suitable for clamping various cutting tools in aerospace, semiconductor, medical and other industrial machining applications.

Technical Parameters
Item (Unit: mm) | Standard Type | Slim Type
Clamping Diameter d | 4-20 | 4-20
D | 15-33 | 10-27
D1 | 20-51 | 14-33
L | 80-160 | 90
Min. Inserting Length E | 15-42 | 15-47
Max. Inserting Length H | 60-210 | 65-110

Features / Technical Specifications

• Dynamic balance: G2.5 at 25,000 rpm; G1.0 at 60,000 rpm
• Runout: ≤0.001 mm (tool holder); runout accuracy within 0.003 mm at 4×D
• Clamping force: approximately 2× DIN standard
• Material / Finish: alloy steel with special surface treatment for corrosion/wear/rust resistance
• Design: extra-long design to support high precision
• Heat treatment & machining: fine milling of key groove after heat treatment to avoid distortion
• Durability: up to 3,000 clamp cycles when used with Conprofe Shrink-Fit Machine
• Typical sizes (Standard Type): clamping diameter 4–20 mm; D 15–33 mm; D1 20–51 mm; L 80–160 mm; min inserting length E 15–42 mm; max inserting length H 60–210 mm
• Typical sizes (Slim Type): clamping diameter 4–20 mm; D 10–27 mm; D1 14–33 mm; L 90 mm; min inserting length E 15–47 mm; max inserting length H 65–110 mm