How to use a single-roller mechanical tool correctly

Single-roller mechanical tools are real all-rounders for roller burnishing. They can be used in a variety of ways and basically always deliver a perfect surface result. In this article, we want to introduce this large group of tools and show you how to use them correctly.

Tools for roller burnishing and deep rolling are available in a wide variety of designs. The design and mode of operation depend on various factors, such as the component geometry, the required rolling force or the component’s hardness. In general, two groups of tools can be distinguished: Mechanical and hydrostatic tools. 

With mechanical tools, the roller is pressed onto the surface by a mechanical force. The roller is mounted or supported in some form and is driven by rotation of the workpiece. There are single-roller and multi-roller tools. In the case of multi-roller tools, several rollers are distributed around the circumference and are supported on a support cone. The rolling force is defined via an oversize of the tool by setting the rollers to a fixed diameter. 

With single-roller tools, only one roller is used, which is usually subjected to the rolling force via a spring system and a bearing and is then pressed onto the surface.

ECOROLL’s single-roller mechanical tools all have the same schematic design. They consist of a clamping device with which the tool is clamped in the machine tool. Clamping can of course be designed however necessary. Whether capto, VDI or cylindrical shank, it can be flexibly designed and exchanged. 

The basic tool body is the significant part. It consists of a fixed and a variable element. Both are connected via leaf spring assemblies. The rolling force is applied in a defined manner by deflecting the leaf springs. With a classic EG tool (for roller burnishing), a general spring characteristic is sufficient. If tools are used for deep rolling, spring characteristics are measured individually for each tool and supplied with a spring characteristic curve. 

Deflection of the spring can be read off the dial gauge. This is available in analog form or as a digital ECOsense version. The spring characteristic curve is then stored directly and the rolling force can be read directly from the dial gauge. Of course, process forces can then be documented and monitored for each process.

The roller head is designed so that the roller can be picked up and positioned in the correct shape on the surface.

This can be seen, for example, in the EG5-32AI tool type. This variant of an EG5 tool uses the basic body of this tool type. However, the roller head is designed in such a way that the tool can also be used to machine bores with a diameter of d = 32 mm or more. This roller head is therefore very long and cantilevered. 

Other variants of this tool series include the EG45-40M and the EG3T. The EG45-40M is a tool for contour machining. The self-supported 40M roller allows concave and convex radii to be machined, as well as cylindrical or flat surfaces. The maximum rolling force is here rather high. For example, the base body is capable of applying a force of 8 kN via the springs (in this case, the roller limits the maximum rolling force to 4 kN). 

The EG3T is the smallest single-roller tool available. Its roller has a diameter of just 3 mm and can smooth smallest cylindrical components with a maximum force of 1,000 N. The tool has been specially developed for use in sliding headstock automatic lathes and is therefore extremely space-saving.

EG tools are very easy to use. No additional form of energy is required for use in the machine tool, they can be programmed in the same way as a cutting tool. Radius correction should be used and infeed be programmed analogous to the cutting depth. 

To change rollers, simply loosen the cage using the front screw. Support roller, cage and rollers can then be replaced. If all three available rollers are worn, they must be replaced. The video shows exactly how this works.