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| bauma presents latest developments in engine technology  The exhaust levels of the EU and the EPA, the reductions of which have been set at specific deadlines, have triggered a lot of innovation in injection technology, exhaust gas recirculation and particle filtering. The visitors to the 28th bauma, which will take place in Munich from April 23 to 29, can expect a complete range of reworked and newly developed engine units. Parallel to that, there will also be many innovations in gear components and in the hydraulics sector.Since the last bauma in 2004, there is another significant construction machine manufacturer, which is equipping its products with its own engines. This is a special status, which many other companies cannot afford or even do not want. They prefer to take advantage of the know-how of the few large system suppliers and assume that they are reacting to legal regulations sufficiently in advance of their taking effect. This is a task, which could only be solved with brilliance and – in many cases – with internal engines measures in the past. This is an important aspect for first users, because there is little space for additional units and other components even in large construction machines. The same or only slightly changed assembly dimensions for engines and a certain continuity for the coming years simply the work of engineers in addition. Where all other possibilities have been exhausted, system suppliers are ready to ensure low particle values with modern exhaust filters, for example. This is often done using a combination of a particle filter, integrated catalytic converter and automatic dosing system. But sintered metal filters are also used, which have a substantially higher storage volume and easy adaptation to different site spaces. However, engine manufacturers have additional problems; for example, if the NOx percentage (nitrogen oxide) is reduced to the required levels via exhaust gas recirculation, the share of the soot particles increases. In addition, the exhaust gas recirculation has a negative effective on engine performance. On the other hand, if engines are designed for the least possible fuel consumption to benefit consumers, the exhaust gas values are too high. This is a vicious circle, which can only be broken with maximum efforts. Construction machines make noise. In addition to the actual application, components such as the drive motor, gears, axles and hydraulic pumps are responsible for it. Change-over control for storage provides a new possibility. It reduces the volume flow and pressure pulsations of the hydraulic regulating pumps in an open cycle for the complete operating range up to 70 percent. They do this independent of pressure, speed and temperature. Tests in actual practice prove that the noise level decreases considerably both for the operator in the cabin as well as in the surrounding area. This makes it possible to avoid expensive measures for noise insulation. Noise emission is not the only important topic for manufacturers and users. The further refining of the load-sensing systems, which enable adapting pressure and volume flow to the respectively current needs of users, remains on the to-do list. Optimized solutions can also be expected in the area of electric capacity adjustment at the 28th bauma in Munich. It enables easier control of machine functions. The design of the control level and joystick in construction machines, which are subject to substantial use, is still a subject that is being worked on. Precise control of components such as the jib and the bucket require solutions, which guarantee unobstructed hydraulic flow with the least possible pressure drop. As a result, less engine performance and less fuel are required in the end. Gears and axles are responsible for converting the power produced in engines into the required movements without much loss and with the least possible noise emission. The manufacturers of these components pay above all attention to modular types of construction for the greatest possible number of different applications to keep costs under control. Despite the conformity, users expect variable equipment models customized to their needs, a long operating life and the least maintenance possible. Especially in construction machines, which always must operate reliably and fast on very different surfaces, a lot depends on precise control of the gears. In connection with electro-hydraulic components, the electronics ensure the suitable gear is used while the driver can concentrate on the actual work. Another step involves acceleration-independent drive programs, which detect the respective state of charge and improve drive performance noticeably thanks to skipping individual gear levels or adapted switching points, for example. write your comments about the article :: © 2007 Construction News :: home page |