Scania Argentina Acquires New Equipments For Performing Double Shot Peening In Truck’s Gear Boxes

     

Soldini, Argentina –  (July 2007) – Scania the world wide leader in the manufacture of heavy vehicles, has recently installed in its plant in the province of Tucuman, Argentina, two new equipments of Shot Peening of last generation, totally designed and produced by Cym Materiales SA.

Since the year 1987 the company Scania Argentina has been performing a shot peening process to all its gear boxes. This Shotblasting process generates compression tensions on the surface of the root of the gear’s teeth and pinions with the object of increasing in 20% the fatigue breaking resistance.

In the last few years, and with the new demands for quality, Scania has had the need of improving the shot peening process that it had been performing, to cover the new requirements that its gear boxes have to comply with.

Thus they decided to update their equipment changing to a new double shot peening process that combines the effects of the conventional shot peening with a second shot peening performed with less intensity. With this new process Scania has achieved to increase 30% the fatigue breaking resistance of their parts.

The equipments developed by Cym Materiales SA totally comply with the strict quality standards required by Scania. The outstanding issues are the following:

·  The equipment uses only one shot size for both types of intensity.

·  By means of an easy programming, the equipment allows to perform simple and double Shot Peening in the same operation cycle.

·  Electronic control of turbine rotation.

o  Perfect adjustment of the shotblasting intensity according to the type of part that it is necessary to process.

o  In case of double shot peening, the equipment adjusts automatically during the operation cycle, for both selected impact speeds.

·  Automatic adjustment of the box control for the different intensities required in the process, in such a way that the highest concentration of shot is always centred (hot spot) on the gears.

·  Carrier device for parts that has control of the gear rotation speed, a parts fastener system and spinning sensors.

·  Flow control of abrasive magnetic valve, Magna Valve, that allows to perform the following:

o  An exact measuring and control of the shot flow that enters the turbine to assure repeatability and homogeneity of the process.

o  An automatic adjustment of the shot flow that enters the turbine according to the impact speed selected.

To control the functioning of the new equipments provided by Cym Materiales, Scania Argentina, received the visit of Engineers Mats Bramberg, Mikael Parssinen and Frank Tomas, from the head office in Sweden, who helped to define the new working parameters.  After three days of adjustments and trials, samples were sent to the Fatigue Laboratory of Sodertalje, Sweden, where the samples were all approved.

Mr. Daniel Carrizo, head of the Thermic Treatment Area of Scania Argentina told us “Due to the increase in the power of the engines that are being used for our trucks, we have had the need of also increasing the quality of our transmission boxes, improving the fatigue breaking resistance of gear-teeth. The purchase of the equipments of shot peening from Cym Materiales, is part of a necessary renovation to adapt to this new requirements of the market.”

“For us the implementation of the new process of double shot peening, was a huge challenge and a great achievement, because we did not count, in all the companies of the group, with any experience at all. So we are very thankful to all the Engineers of Cym Materiales that have participated in the development of these equipments, because of all their help and high professionalism, and to the fact that they could understand our requirements, offering us a product according to our needs.”