BCT: Automatic machining of individual parts
During tool and mold construction, as well as during the manufacture and repair of aero-engine components, the real machining strategy differs from the previously planned approach. Parts are not clamped in the foreseen position and with the foreseen orientation – or they display individual differences in shape caused, for example, by production-related fluctuations or wear during operational use. Taking account of these deviations usually requires complicated manual machining. This does not have to be the case!
BCT solutions capture the position and shape of each individual workpiece prior to machining and transfer a predefined strategy to these parts. They do this separately for each part but nevertheless in an automated manner! We call this approach Adaptive Machining. Learn more about AM developments, applications and solutions. Ask us how we can solve your problems!
+ consider individual part shapes, automatically
+ avoid a long and complicated manual setting-up process.
+ reduce the requirements for the fixture, which in turn lowers costs.
+ lower the number of rejects.
+ miminise manual rework.
BCT’s system OpenARMS (Open Adaptive Repair and Manufacturing Software) is employed in situations where the individual shape of parts – as well as varying clamping positions – have to be taken into account. The integration of different CAD and NC formats permits smooth cooperation with customer-specific systems. OpenARMS can be connected to various NC controls and the integrated measurement module supports both tactile and optical sensors. Based on information on the current part, geometric adaptation of the manufacturing program is undertaken. During this process, the specifications are automatically transferred to every single individually-shaped part. The close connection to NC machines makes it possible to carry out automatic processing – similar to series manufacturing – despite differences between the individual parts.
OpenARMS is the link between the CAD/CAM description of the part and the real individual parts. This adaptation is not limited to special manufacturing methods. When turbine blades are milled or ground, for example, the adaptation of the machining paths makes the laser powder fusion welding process more precise. During the processing of carbon-fiber composite parts, OpenARMS permits targeted material removal on each single, individually shaped part as a preliminary step prior to repair.
Learn more about developments, applications and solutions in our brochure – or test us!
+ Taking account of the individual shape and position of the parts
+ Integrated capture of part shape and position via either optical or tactile sensors
+ Automated machining via direct connection to the machine centers
+ Adherence to tight tolerances even for individual shapes
During the manufacturing of parts, the exact alignment often presents some challenges. These problems may be caused by production-related part deviations, simple fixtures or differences in their handling:
– Nevertheless, machining of the part must take place in the planned position.
– Nevertheless allowance has to be considered when processing casted or printed blank parts to “fit” the final geometry into the blank part.
Additionally the solution should:
– not require using the CAD/CAM systems, again
– adopt the previously defined and tested NC programs
– take characteristics of machine and fixture into account
OpenFIT will solve such or similar processing tasks.
In a first step CAD model of part and fixture as well as the manufacturing program will be imported.
Definition and execution of the measurements to capture the position of the parts inside the machine are realised using the integrated measuring module (tactile probing). Direct communication with the NC controller enables the automatic transfer of measuring programs and results.
Based on this, OpenFIT adapts the position/orientation of a planned machining sequence in minimising the deviations. There is a choice to adapt the NC program, directly or – more elegant – just to transfer the description of the new working coordinate system to the controller. In this case the NC program remains unchanged! The adjustment will only change the orientation in which it is carried out.
Using the functionality of option BestFIT position and orientation of the process are adjusted.
With the extended function of option VolumeFIT, allowances are taken into account as well. This guarantees, that appropriate allowances are available to realise reliable processing of the parts.
+ A complicated manual alignment process is no longer necessary.
+ The requirements for the fixture are reduced, thereby lowering costs.
+ You have control over the machining overmeasure (VolumeFit).
+ The program can be easily integrated into the present process workflow.
To be able to take account of individually shaped parts or special clamping situations within the scope of adaptive machining, we first have to determine the differences between the actual situation and the nominal situation (CAD). All adaptive systems either come with integrated measurement devices – or are connected to such devices – for this purpose.
In the simplest case, the differences can be determined with touch trigger probes. In most cases, these have already been incorporated in the NC machines by the machinery manufacturer and permit reliable measurement of individual points. The BCT solutions for adaptive machining include integrated measurement modules with which measurement sequences can be defined and results displayed.
However, if the machining task requires a large number of measurement points, laser line scanning is more suitable. With this method the distances between the sensor and a strip projected onto the part are evaluated point by point. This method is very fast and simultaneously delivers a large number of measurements points. These measurement procedures can be defined with OpenSCAN. The precision of the measurements is increased by special compensations – in particular, when these are undertaken from different directions (OpenSCAN is available for the Sinumerik 840D).
+ Measurement of the part in the machine
+ Short measurement times together with a high resolution
+ Capturing part states for various purposes
Adaptive systems always consist of a combination of measurement technology and NC machines. Automated machining requires the exchange of information and data between individual components. To achieve this, OpenARMS is usually connected directly to the machine center. With this configuration it is possible to transmit measurement programs, receive measurement results, and transmit and run the adapted NC programs. We support the most commonly used control types. Please don’t hesitate to ask us.
In addition to software, BCT supplies the matching sensor technology for capturing the actual geometry, the clamping elements and other elements up to and including the complete systems including the NC machines of your choice.
An application-oriented briefing on the systems ensures their quick and economic use and is thus a matter of course. Users are put in a position to set up their own projects and define their own processes.
+ Delivery of the complete system from one source
+ Smooth integration of different components
+ Realisation of complex process workflows
We can only improve a process if you have enough information on it. If we look at a milling process, for example, we see that vibrations, milling forces, rpms and feed can be measured. In the area of laser powder fusion welding, we see that a large number of parameters – ranging from the laser output to the temperature of the melting bath – can be recorded.
With OpenDATA, moreover, we can now answer the question of which values are to be measured – and at which locations – on the part! This local resolution permits a fast and practice-oriented insight into the particular process and thus delivers reliable information for optimization or monitoring.
OpenDATA combines positional information from the machine with measurement values supplied by external sensors.
We will find a solution to your problem as well!
+ Precise assignment of measurement values to the part itself
+ Support of a wide range of sensors (National Instruments interface)
+ Easily understandable visualization of measurement values