The main drawback with wiper inserts is the higher cutting pressure. The wiper radius is acting as a large nose radius, and the radial cutting force component is significantly much higher than with a standard insert, and this increases the risk for vibrations. In stable setups, this is not a problem, but it can be a problem in many operations:
- when machining “smaller” inner diameters on gears
- when machining long and slender parts like shafts
- when machining components clamped in only one end
A solution for these difficult operations was developed by Seco, called the HelixTM wiper, where the insert chamfer angle varies around the insert nose radius. This significantly decreases the radial cutting force component (as shown in the figure below with up to a 30% decrease), allowing the wiper technology to be used, with all the productivity and component quality benefits for the customer.
The Helix wiper has been very successful, allowing customers to take advantage of the wiper technology. Standard inserts are today available in the following geometries:
Below are two examples of gear machining with Positive HelixTM wiper inserts. Left is an example of a small ID turning operation, the diameter is 32 -0.012/-0.028 mm and the surface roughness requirement is Ra=0.5 mm. Right is an OD turning operation, where tool wear caused vibrations after only 38 minutes TIC. The Helix wiper allowed for almost double tool life.
For more information, please contact your local Seco representative, or our Advanced material (PCBN/PCD/CERAMIC) team.
Author: Henrik Sandqvist Product Specialist SECOMAX PCBN/PCD/CERAMIC SECO TOOLS Shanghai CO., Ltd. Level 2, Building 8, 456 HongCao Rd., Shanghai 200233, China Office: +86 21 5426 5849 Mobile: +86 185 1520 6942 e-mail: henrik.sandqvist@secotools.com |