Part marking – highly efficient techniques and methods
The special feature of the marking tools developed by us is the non-cutting marking process. As with engraving, the marking contour is always traced by the machine axes. The feed speeds (when approaching the marking position as well as when traversing the marking contour), however, are massively higher than during engraving. The same applies to the service life of the marking needle.
As standard, all tool versions are equipped with a cylindrical Weldon shank of 20 mm.
In principle, however, all tools can also be supplied with integrated tool holders such as HSK etc., some of which are even available from stock.
The desired marking is effected by the movement of the axis control of the processing machine.
The process is essentially the same as engraving with an engraving cutter. Exception: As a rule, work is carried out with the machine spindle in a stationary position. If the machine spindle cannot be brought to a standstill, the lowest possible speed should be set.
When using the scratching and roller embossing tools, the operator merely requires the movement of the machine axes for running along the marking contour.
The use of the micro-percussion tools requires additional compressed air or coolant, which can be activated through the machine spindle during the processing cycle.
The majority of control system manufacturers now offer corresponding marking programs for alphanumeric text markings.
For special marking tasks by means of serial numbering, transfer of real-time data etc. – as well as for the marking of Data Matrix Codes or QR Codes – we work together with corresponding partner companies.
Please get in touch with us if you require technical support!
The minimum required coolant pressure is approx. 2 bar.
It is important to note that for applications below 5 bar, the WS type has to be chosen.
Air pressure within a range of 3 – 8 bar is required for tools in the standard version.
The reinforced PP versions (for deeper markings) require a minimum pressure of 2 bar.
Micro-percussion tools:
The depth of the marking is dependent on the available coolant pressure or air pressure, and is max. approx. 0.2 mm with the standard tools. With the tool versions WSP-20 or H-20 PP it is possible to achieve marking depths up to approx. 0.4 mm.
With the tool types WSRX-20 or HRY-20 and HRY-20 PP it is possible to reduce the marking depth precisely to the required dimension
Scratch marking tools:
Using the R-20 it is possible to achieve marking depths up to approx. 0.3 mm
With the RM-20 or RM-12L the maximum attainable depth is 0.1 – 0.2 mm
Roller embossing tools:
With these types of tools the marking depth is usually less than 0.1 mm. Due to the change in the surface structure the markings are still good visible (as scratches on surfaces).
The marking depth is always dependent on the available coolant pressure or air pressure.
With the adjustable tool types WSRX-20 or HRY-20 and HRY-20 PP it is possible to reduce the marking depth precisely to the required dimension.
All of our marking tools are equipped with an automatic distance compensation function. This means that the marking depth is always the same, even when marking on uneven surfaces.
Micro-percussion tools:
Due to the pressure pulse control, the marking needle is no longer pressurised upon contact with the marking surface. Hence, the machine spindle is only subjected to a minimal axial pressure of a few N.
Scratching or roller embossing tools:
The strain depends on the available pre-tensioning pressure of the tools. In lateral direction this is a few N, in axial direction a maximum of 240 N.
Scratch marking and micropercussion tools:
Due to the extreme hardness of the marking needle (92 HRC), it works virtually wear-free. Experience has shown that no wear can be detected even after several weeks with shift operation. In addition, the marking needle can be quickly and easily replaced in all tool types.
Roller embossing tools:
Due to the pivoting small carbide ball (diameter 1 mm), wear on the marking needle is significantly higher with these tools. We therefore recommend only using the roller embossing tools for applications where very high visual demands are placed on the marking.
This depends on various criteria, such as the hardness of the workpiece, the quality of the workpiece surface, the desired result of the marking (visual quality, marking depth), as well as the available machine equipment on which the tool should be used.
Please get in touch with us if you require technical support!
Yes, as there is no need for a rotating machine spindle for non-cutting part marking, this is possible without any problems. Gravostar offers various tool versions with which part marking can be carried out at right angles or also at an angle to the axis of the machine spindle.
Please get in touch with us if you require technical support!
No material is removed during micro-percussion unlike engraving or laser marking. This means no damage to the material fibres and, as a result, there is virtually no reduction in the stability.
Because with micro-percussion only one fine dot is placed after the other, also very thin workpieces can be marked without any deformations.
Shorter marking time
In contrast o engraving, gravostar operates at very high feed rates of more than 5‘000 rpm. (material-dependent). The infeed or piercing speed can also be as fast as desired with the tools.
Insignificant tool wear
There is no risk of tool breakage due to wear or a too high feed rate. Furthermore, the marking remains practically unchanged even if the needle is slightly worn (no burr formation). The advance and plunge speed can also be set as quickly as required with the tools.
Maximum process reliability
In comparison to engraving, quality and process reliability when marking with gravostar are considerably higher.
Automatic distance adjustment function
Due to the automatic distance compensation (between the workpiece and the needle) workpieces with an uneven surface or larger dimensional tolerances (e.g. raw cast parts or round shapes) can also be marked without any problems.
It is correct that the processing time of the “expensive” production machine is extended by several seconds. It is therefore impossible to provide a general response to this question and it must be individually assessed with every task.
An alternative is post-marking, which however requires an additional working sequence. In doing so however, it is necessary to consider the following points:
As an overall result, this means that: despite minimum extension of machine processing time, the marking integrated in the metal cutting process is often the most economic and above all most reliable option.
No, the operation of all marking tools manufactured by us is completely maintenance-free.
It is necessary to note in general: in contrast to engraving, with gravostar tools the marking depth is not set through the tool distance!
It is necessary to note in general: in contrast to engraving, with gravostar tools the marking depth is not set through the tool distance!
QR codes and Data Matrix codes are no problem with gravostar’s needle embossing tools (smallest DMC size: approx. 8 x 8 mm). The marking depth and width, the radius and the angle can be adapted to meet the required specifications. gravostar tools can automatically compensate for dimensional variations or unevenness in the marking surface of up to 3 mm. This ensures a uniform marking depth even on irregular marking surfaces (e.g. on rough castings, etc.).
Depending on the specifications of the CNC machine tool, we can offer various models of tools powered by compressed air or coolant.
Good to know!
What makes the gravostar marking tools we have developed so special is the non-cutting process. Needle marking is one of the few approved marking processes permitted in the aviation industry, as no material is removed; instead, material is simply displaced and compacted.
This is fundamentally straightforward using the gravostar marking tools, and a number of customers have already realised this process.
The greatest challenge here lies in the software for generating the DMC, in order that the individual dots can be approached by the CNC machine.
However, appropriate solutions are now available from individual control system manufacturers.
The respective data is generally automatically read out from the machine control system or the network.
The FAQs of the gravostar marking tools conveniently in a PDF for downloading
Mit Gravostar Kontakt aufnehmen