SACMI Newest Innovations for the Powder Metal Industry: Helical Gear and Die Wall Lubrication ￼
Productivity, flexibility, reliability and customers’ satisfaction are the pillars of SACMI’s Powder Metal (PM) solutions: hydraulic and electrical presses, high temperature kilns and advanced automation solutions. The worldwide scenario is rapidly evolving with new needs. Being flexible and finding new ways to keep in line with the latest developments has become essential. As a matter of fact, SACMI/IT is keeping on studying effective solutions to assist its customers to get to a greener production in a fully digital integrated way.
Also the automotive industry, and consequently the PM field, have undergone significant turnarounds. Final products, as well as vehicles, have changed and, at the same time, PM producers have developed different needs than before. Right from the market need to produce more complicated and particular parts, SACMI has invested in the development of new solutions to improve the potentiality of Powder Metallurgy. Starting from the adoption of new concepts in its presses to make PM producers able to compact new complicated parts, not feasible so far, to the constant presence at the side of the customers to assist them in the research of new components to use in e-vehicles, that are now representing a big opportunity for the PM industry, SACMI has found a new approach to meet these innovations.
The results can be found in the Helical Gear (HG) System, that can be implemented to all well-known MPH hydraulic presses and that permits to press helical gears parts, and in the Die Wall Lubrication System, a device to install on the presses, that allows to use powders containing few lubricants and thus obtain products with very high green density. Going into details, the HG System allows to produce complicated parts with the utmost simplicity, thanks to the possibility of compacting components with angles up to 30° and more and a density up to 7,5 g/cm3. In fact, with its revolutionary design, through a single system, it is possible to produce all possible helical gears, without the need for tool-to-tool systems.
Programming a new helical part can be done easily from the control panel of the machine thanks to the software integrated in the press; moreover, the tool set-up of helical parts is as simple as for standard parts. In fact, it is limited to the replacement of active tool parts, in contrast to different systems which require time-consuming and complicated activities. This means also a money saving for the users, thanks to the fact that it will no more be necessary to have additional mechanical parts dedicated to each component to be pressed. The software behind the system has been fully developed inside SACMI and therefore, it is perfectly integrated in the API, that is the well appreciated programming software available on the whole MPH series. A strong point is the flexibility: in fact, the system allows for inner and outer helical profiles using a combination of rotating movements of upper axes, lower axes and die plate.
Also concerning the parts’ geometries, there is the possibility to keep all levels of the press, also with rotating axes, that brings to a machine that is slightly higher than the standard one. However, till 250 t, the presses equipped with HG system can be installed on the ground avoiding the pit. Compaction can occur both with cold and warm die, due to the possibility to heat it up or cool it down according to the final part to produce. MPH presses with HG System keep their very high production rate as well as the finest tolerances and extreme precision, without any reduction of maximum pressing force. HG tools have now a much longer life than the actual one, because of reduced friction generated with the new HG System, comparable to cylindrical tools, and this further increases the economic advantage of this revolutionary system compared to the existing ones. In order to facilitate the switch from cylindrical to helical components, the presses can be equipped with a semi-automatic system to exchange two adaptors in order to produce cylindrical and helical parts with a single machine. Developed on the MPH202, the system will be extended to the complete range of SACMI MPH presses, starting from the low tonnages to the higher ones. In this way, the customers will soon have a new solution that allows the production of new complicated parts creating new business opportunities.
As regards the Die Wall Lubrication System, on the other hand, the great advantage which SACMI saw in this investment is the ability to produce high-density components, which offers manufacturers a greater capability to meet today’s market needs. In fact, these have changed throughout the years due to factors such as the electrification of cars and the continuous demand for cost reduction.
For example, to produce high torque transmission gears, the traditional machining technology has been the preferred process so far, because of the high demands in terms of mechanical properties and dimensional stability. However, the possibility of using powder metallurgy to produce these components makes it possible for PM players to widen their product range.
In this perspective, SACMI successfully implemented a special and new concept called Die Wall Lubrication System on its presses. This technical improvement allows for the production of high-strength and high-density sintered components. Parts produced with this technology thus open for PM new applications thanks to several advantages. Before anything else, the same press equipped with the Die Wall Lubrication System to produce high/full density parts can also be used to produce standard PM parts. Besides, green density can get up to 7,70 g/cm3 and green resistance over 60 MPa, characteristic that grants also functional mechanical processing before sintering. In addition, the ejection force is reduced up to –50 % with lower wear of the tool, thanks to the lubricant sprayed directly on the mould. Also, the dimensional and geometrical stability of the parts during the sintering process is highly increased. And finally, mechanical properties of the final product, such as yield strength and tensile strength, are significantly higher.
SACMI is available to adapt the solution for customer’s case studies and needs. One MPH202 with die wall lubrication and one with helical gear system are installed in Imola and available for show and trials, so that interested customers can better understand the way of working and the potentialities of both systems. Both the new developments have in common the user-friendly API press software, that lets the operator program the cycle in a quick and reliable way without the possibility of making mistakes that could damage the press. More than the cycle programming, the operator has also the possibility to simulate the pressing cycle in advance, in order to view and examine the axes’ movement; the operator can fine tune the axes’ regulation according to the results obtained while pressing, and in this way any defects resulting on the pressed part can be promptly corrected. Finally, the API software provides the possibility to have an automatic regulation of the process parameters during the normal machine running and therefore grant that the parts’ parameters are kept within the target range. API Software, is provided to all the customers in “Software Press” and “Software Office” versions.