The manufacturing or overhauling of aero structure and airplane engine parts does in many cases involve the peening process. Peening is generally applied to increase resistance to fatigue and stress corrosion failure. Depending on the particular case, shot peening can multiply the service life of a part.

For aviation companies involved in peening it is often not cost effective to have its own equipment, since the machinery including infrastructure is very expensive. However, if they consider an outsourcing, they must be sure that the "turn around time" is very short. This is especially true for engine repair shops, since the whole engine, worth several million dollars, may be waiting for this particular part. Furthermore, since there is no non destructive test method to confirm the effect of peening, a transparent quality control and documentation is vital. This to make the customer feel comfortable with the process.

When GT-Baiker Metal Finishing PTE LTD decided to open a peening job shop it took all this into consideration. It invested in a state of the art CNC peening machine. There is hardly any part, this CNC peening machine can not handle. Be it  engine discs, hubs, blades, airfoils, landing gears, aero structure parts, gear boxes, or other parts, that have to be treated, this application is flexible enough to cope with it. Looking at all the high end options integrated at the installation, it is likely to be the most sophisticated peening machine in the Asia Pacific region. The decision to open this job shop in Singapore is partly based on the exceptional large number of aviation companies in the near vicinity. But in addition, by choosing Singapore, being a regional hub for South East Asia, it will be easy to provide a good service also to customers outside of Singapore.

CNC Multi-Purpose Peening Machine at GT-Baiker Metal Finishing PTE LTD:
The machine is equipped with a gantry robot which includes 4 CNC axis for the movement of the peening nozzles. The axis can interpolate between each other to cope with complicated shapes of work pieces. The programming can be done with a "teach-in" remote control unit, which can be taken into the cabin. This to simplify the programming. Up to 100 programs can be stored in the CNC. The work pieces are to be placed on an indexing turn-table via an electrical crane which is built onto the machine. The nozzle and work piece fixtures predetermine the position of the parts to allow a program to start immediately. A choice of 3 shot sizes is available within the system. For further shot sizes, one of the 3 storage silos must be discharged. The peening media is continuously processed in terms of size and shape in order to fulfil the strict specifications of the aviation industry. The flow rate of the peening media as well as the peening pressure are controlled within tight tolerances. In case one of the important process parameters is not within given tolerances, the machine will shut down and a protocol would be printed out automatically to document the malfunction. If everything works fine the peening parameters are recorded automatically on the hard disk of the computer, but can also be printed out on request. The same computer system also visualises the process. Two off-line programs have access to an extensive data base in order to enable the operator to choose the most efficient peening parameters. Data such as peening pressure, flow rate, revolution of laces, etc. is provided to reduce the testing period for determining the parameters. Furthermore, the programs also provide a tool to generate and interpret the so called ALMEN Saturation Curve, which is a standard test procedure in the peening process.
The machine consists of 2 standard dosing units for up to 10 kg/min. and one high precision dosing unit for very small flow rates between 20-600 g/min.. Having access to over 100 standard internal peening or special application nozzles the machine is equipped to handle the changing requirements of a job shop. Even holes as small as ?2.5mm can still be treated.

The peening machine has been delivered by the Swiss manufacturer BAIKER AG in Zurich and is built according to the European regulation in terms of environment and operator safety. Furthermore, it has a noise emission of less than 73 dB(A). In order to make sure that machine has as little down time as possible, the manufacturer recommended to equip the machine with a modem to allow remote support from Switzerland. Doing so, a quick access to all PLC & CNC programs, as well as process parameters, is possible.
Having this sophisticated equipment in conjunction with the expertise of the shot peening process, this new job shop in Singapore will be able to satisfy the high demands of the aviation industry.

For Information:
GT-Baiker Metal Finishing PTE LTD
10 Loyang Street, Singapore 508844
Tel.: +65 6542 8993
Fax: +65 65429896
e-mail: gtind@cyberway.com.sg