Vol. 8
July Issue
Year 2007


in Vol. 8 - July Issue - Year 2007
Special, But Not Only Suited For Edge Preparation Of Carbide And Powdered Metal Tools

Drag finishing machine for high precision and reproducible edge preparation

Studies at manufacturers and end-users work shops resulted in a tremendous improvement of uptimes of ground carbide and powdered metal tools.
The drag finishing technology is a special process for finishing of high-quality, delicate work pieces with many contours and complex geometries especially suitable for extremely hard, difficult to machine materials. An extremely compact and hence small type of this machine concept is the M-TMD 6/2. Equipped with 6 clamping stations, this mini drag finishing machine was designed for the edge preparation and surface improvement of carbide tools as end mills, drill bits, inserts, hobs or thread milling cutters. Geometrically precise edge radiusing combined with a surface improvement prior to hard coat, removal of droplets and top lets after coating result in optimum lifetime and uniform production quality of the tools.

The TROWAL drag finishing technology widens the field of precision surface treatment and edge radiusing in shortest cycle times and reproducible quality.
Pneumatically fixtured tools are „dragged“  through a stillstanding abrasive media mass with individually rotating satellites. Here, the relative movement between work pieces and abrasives results in an edge radiusing to a new defined, uniform radius of 5 up to 80 µm in shortest time cycles without chipping at the cutting edges. The delicate tools or other components cannot touch and damage each other during the finishing process. Speed control via frequency converters and PLC-controlled programs allow flexibility in machine setting for all processing needs. The processing parameters, such as rotational speed and immersion depth etc. can be adjusted and changed individually at the machine. Furthermore, all processing sequences will be controlled by PLC programs for exact repeatability.
The flexible system technology provides the suitability of the mini-drag finishing machine for many other fields of application. Examples: implants, turbine blades, sintered parts, precision elements for pumps and compressors etc. up to a maximum parts weight of 25 kgs.

Author: Rolf Jürgen Picard
For Information:
Walther Trowal GmbH & Co. KG
Rheinische Straße 35-37
42781 Haan, Germany
Tel. +49.21.29 571-0
Fax +49.21.29 571-225