240mm Extension Sleeve MK4 to MK3 Hardened Ground, DIN 2187 - TECWERK

Benefit from the combination of DIN 2187 compliance, a fully hardened and ground finish, and a long 240 mm overall length for stable tool extension and consistent concentricity; order the extension sleeve directly via Metav Werkzeuge or ask our consultants if needed.

Extension sleeve DIN 2187 MK4×MK3, hardened and ground — TECWERK

A Extension sleeve DIN 2187 MK4×MK3 designed to extend Morse taper tooling with high precision and a hardened, finely ground bearing surface for machining applications

• DIN 2187 standardised accuracy version
• Fully hardened and ground inside and out
• Adapts MK4 to MK3 Morse tapers
• 240 mm overall length, D 36 mm

Reliable alignment and reduced runout for consistent machining

The extension sleeve follows DIN 2187, supplying a standardised interface that maintains tool alignment across repeated insertions. Its fully hardened body and surfaces ground inside and out reduce taper wear and help preserve concentricity during extended runs. For workshops that prioritise repeatable results, the accuracy execution minimises radial runout and contributes to consistent hole quality and surface finish. The adapter construction also reduces the risk of fretting between mating tapers, prolonging the service life of both tool and holder.

Greater reach while retaining secure taper connection

With an overall length of 240 mm (L2) and a working length L1 of 122.5 mm, this extension is suited to operations requiring extra reach without compromising stability. The combination of an external MK4 taper and internal MK3 taper lets the component be used as a reliable link between different Morse taper sizes, enabling deeper access in bores or extended tooling setups. The stated diameter D 36 mm gives a robust cross-section that resists bending under typical machining loads, so the tooling stack remains rigid and predictable.

Workshop-grade durability and low maintenance

Manufactured in an accuracy grade and treated to be entirely hardened, the sleeve is supplied ready for service with minimal preparation. The ground internal and external surfaces ensure trouble-free seating with Morse taper tooling and lower the need for frequent rework or adjustment. Where replacement intervals impact uptime, the hardened and ground finish helps retain dimensional integrity, reducing the frequency of swaps and supporting steadier production cycles in small and large workshops alike.

Broad compatibility across Morse taper tooling

Intended for use with tools and holders featuring Morse tapers, the component integrates seamlessly into conventional drilling and tooling systems that adhere to DIN standards. The adapter’s geometry and finish make it appropriate for retrofit tasks and mixed-equipment environments, offering a straightforward technical solution when a change of taper size is required. The standardised design also simplifies inventory management: one precision sleeve covers a defined adaptation need while matching existing tool protocols.

For procurement of the TECWERK extension sleeve with DIN 2187 accuracy and a 240 mm overall length, contact Metav Werkzeuge for tailored supply and technical advice.

Technical data

• Article number: 2000832365NW
• Standard: DIN 2187
• Product: Extension sleeve
• Manufacturer: TECWERK

Facts

• Overall length L2: 240 mm
• Working length L1: 122.5 mm
• Diameter D: 36 mm
• Packaging unit: 1

Special features

• Accuracy execution according to DIN 2187
• Fully hardened construction
• Ground inside and out
• Inner taper: MK3
• Outer taper: MK4
• For tools with Morse taper

FAQ

What standard does the adapter comply with?
The adapter is manufactured to DIN 2187, ensuring standardised dimensions and fit for Morse taper tool compatibility.

Which taper sizes are connected by this sleeve?
This sleeve adapts an external MK4 taper to an internal MK3, enabling secure mating between those Morse taper sizes.

How long is the extension and what is the effective working length?
The extension has an overall length of 240 mm with a working length (L1) of 122.5 mm for extended reach in tooling assemblies.

Is the component heat-treated or ground for accuracy?
Yes, the sleeve is completely hardened and ground both internally and externally to provide an accuracy execution suitable for precision tooling.

Which diametral size does the sleeve have?
The sleeve features a diameter of 36 mm (D), offering a solid cross-section for stable performance.

Manufacturer / Responsible: NORDWEST Handel AG, Robert-Schuman-Straße 17, 44263 Dortmund