In recent years, offset printing machine manufacturing technology has developed by leaps and bounds. From the recent large-scale printing equipment and equipment exhibitions in the country and provinces, we have seen that sheet paper offset presses, which represent China ’s higher printing press manufacturing level, are 03 The 05 machine has almost disappeared at the exhibition, and the expandable unit or multi-color machine has become the mainstream product at all levels of various exhibitions. These machines are functional, quality, regardless of shape, man-machine function design or The visual appearance has already approached foreign brand machines, and some performance and indicators have been comparable to internationally renowned brands. However, the expectations of users of offset presses for the use of equipment are also getting higher and higher. The human-oriented design concept of humanity has become the common pursuit of the supply and demand sides, especially the protection of the environmental conditions of machine operators, reducing the skills of operators and reducing labor. Intensity has not been given due attention as a secondary contradiction in the past. Now these secondary contradictions have risen to primary contradictions and become the focus of common concern.

The operating speed of offset presses used to be around 10,000 printings per hour, and the impact of noise on people was often ignored. Taking the folio offset press in foreign countries as an example, most of the limit speed has reached l5000 to 16000 printing per hour. Many domestic machines are also sprinting towards this limit speed. The increase in printing speed greatly increases the difficulty of machine design and manufacture. The topics that need to be tackled are exposed. For example, the noise of the machine has increased significantly. Although the domestic offset presses also paid attention to the noise reduction problem in the past, most of the energy was focused on the rule system and the paper delivery mechanism, because these two parts have many reciprocating swing devices, and the cam mechanism moves by the gap. Composition, large inertia, is recognized as the core organization, and requires high precision. They are not only a source of high noise, but also have a crucial influence on the registration of printed products.

People think that the main contradiction is to grab the paper rule system, because they are the heart parts, the parts that people pay most attention to, analyze the speed, acceleration magnitude, stress status from the cam motion, select parts materials, heat treatment process requirements, etc. , Strict and serious efforts to tackle the problem, in fact, in recent years, with the efforts of various manufacturers, the paper feed system of the printing press has indeed been greatly improved, even in the high-speed printing state, the reference accuracy and machine noise are significantly improved and Improvements, such as Beiren ’s N300, Shanghai Guanghua ’s PZl020, Jiangsu Rugao ’s Changsheng series machines, etc., their regulations and paper delivery mechanism design and manufacture have reached a high level, but they are another major noise source for offset presses. The improvement of components is relatively slow.

The high-speed friction between the sleeve roller chain and the guide rail driven by the offset printing machine is one of the main noise sources of the machine. Reducing or eliminating the noise of this component was also a problem for domestic and foreign offset printing machine manufacturers. Reduce the noise generated by the friction between the chain guide rail and the roller chain of the take-up roller. The fully enclosed guide rail solution is adopted to improve the manufacturing accuracy of the roller chain guide rail by reducing the gap between the guide rail and the chain roller. When climbing or passing through a circular arc, the chain can only be close to the surface of the guide rail. The centrifugal inertial force of the chain is eliminated by the guide rail constraint, and the running noise is partially controlled. Of course, the guide rail cannot be made very precise, and the gap cannot be absolutely absent. This kind of noise reduction measures have higher requirements for design and manufacturing, and relatively higher requirements for the lubrication of the contact surfaces of the chain and the guide rail, because if the lubrication is insufficient, the chain will run poorly, the wear will increase, and even the card will become stuck. Resistance phenomenon. Some manufacturers have improved the design of the guide rail curve. Instead of using a simple arc at the point where the chain needs to climb, a function curve with a small acceleration value is used. The two-phase back arc at the inflection point of the curve of the guide rail turning Arrange a straight line between them, so as not to suddenly reverse the centripetal acceleration of the row of teeth, so as to reduce the impact vibration during the operation of the chain guide. In addition to the shape and accuracy of the improved design of the delivery chain guide, some manufacturers have made bold attempts in the selection of guide rail materials. For example, some manufacturers' products use engineering plastics for the chain guide, like reinforced nylon, but due to the nylon The promotion speed and range of the self-lubricity changes caused by the difference in material composition types and the thermal deformation in the use of drying and drying devices are affected to a certain extent.

Recently, some companies have tried to use new materials with special carbon fiber composite process technology to produce guide rails with satisfactory results. Jiangsu Rugao No. 2 Printing Machinery Factory cooperated with experts from Xi'an and Shanghai Institute of Materials to conduct bold practice tests by using different formulation processes. Finally, we successfully developed a self-lubricating, maintenance-free, oil-free, wear-resistant, shock-absorbing and noise-reducing effect. The paper conveyor chain guide has an ideal effect. Due to the self-lubricating mechanism of the guide material, the friction coefficient is small, the resistance is small, and the wear is low. To achieve maintenance-free function, especially when printing large amount of ink on coated paper with high printing speed, the ink is not easy to dry. In order to prevent smudging, often the toner needs to be sprayed off the paper receiving part of the printer, and the dust is evenly distributed When the surface is flying, the oil stains of the ordinary metal printing machine guide rails will be covered with dust at this time. The operator is strenuous when cleaning and maintaining the equipment, and the removal is not complete. The dust on the surface of the guide rails will accelerate the wear of the machine parts. The guide rail of the new material realizes free of oiling and maintenance, and the dust removal work is very easy. The new material guide rail has a self-lubricating function with a small friction coefficient, and there will be no movement or jamming. The power consumption of the whole machine is low, and the resistance The characteristics of high temperature are more suitable for equipped with multi-row take-up chain offset press with glaze drying function. The unique shock absorption function of the guide rail is very beneficial to reduce the noise of the high-speed running chain. The reduction of machine vibration and noise reduction can effectively improve the working environment, improve the stability of the machine, and even help improve the printing quality of the machine.

The use of special modified carbon fiber composite engineering guide rail materials on offset printing machines is a bold attempt to use new materials and is the result of innovative thinking. It is exciting to compare the effects through preliminary inspection and control. Many of its advantages are gradually recognized by people. The continuous improvement and adjustment of material technology can be believed that its performance will be more perfect.

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