The latest trend of the hottest web offset printin

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The latest trend of web offset printing wheel

after decades of development, web offset printing wheel has made great progress in technology, but this progress has not stopped, and its performance is still being improved. Shaftless transmission and jointless technology can be said to be the most important technological progress. These two technologies make the rubber tyred machine realize high-speed, wide width and large-scale, and the production efficiency is further improved

these two technologies were first developed by hellis, a web offset printing wheel manufacturer in the United States. In the 1990s, as the company that mastered the key technology of the new generation of high-speed rubber tyred machine at that time, hellis developed these two technologies and manufactured sundayprrss rubber tyred machine. After that, Heidelberg company, which acquired hellis, further improved stiimay PM and took it as the target of high-speed commercial turbine; Heidelberg company extended this achievement to the newspaper rubber tire machine and developed mainstream. Due to the continuous excessive development investment, things backfired, and the surrounding business fell into a recession. Therefore, the rubber wheel Department sold the American Gauss company

1 shaftless drive - the standard configuration in the future

the main drive of the traditional printing machine is transmitted from the main motor to each machine through the drive shaft, gear and belt. The musk damage of the mechanical parts of these parts leads to the frequent occurrence of printing faults. The torsion and vibration of the transmission shaft during acceleration and deceleration are the reasons for the double printing. Each printing machine is equipped with independent drive motors (especially on the cooling device and folding machine) to realize the synchronous operation of these motors by electronic control, which is called shaftless drive. Due to the progress of digital control technology, the synchronous operation accuracy can be much higher than that through the connection of mechanical parts between machines. In particular, the advantages of reducing lubricating parts, being conducive to maintenance, and the unused unit can be simply stopped, increase the flexibility of the machine

with the cost reduction brought about by the mass production of special motors and electronic control devices, the shaftless drive, which is good at maintaining the stability of printing crystal quality under high-speed operation conditions, seems to become the standard configuration of rubber tyred machines in the future. The further development of shaftless drive is gearless drive. The printing plate cylinder and rubber cylinder are equipped with independent special motors, and gears will no longer be used in the printing unit

2 non-stop conversion of plate cylinder

the system developed by applying shaftless drive technology, of which the eye-catching is the non-stop conversion of plate cylinder. For occasions such as printing the name of the branch or the postal catalogue of some goods on the advertising leaflet of the chain store and replacing it with English or German, it is only necessary to convert the black board printed by the printing machine into the corresponding black board. This kind of printing of changing store name or text is realized through instantaneous drum conversion under the condition of maintaining the normal speed of the printing machine

drupa 04 demonstrated the technology of flying platechange on Roland. The third to sixth machine saws of the demonstration equipment are used for four-color printing, and the first to second machines are used for black printing of different texts. The first unit prints English. After printing the specified number of copies, the second unit with German printing plate enters the pressure on state, and the first unit is off pressure at the same time. Under the condition of maintaining the maximum printing speed of 70000 sheets/hour, the black version conversion is completed instantly, during which only a dozen sheets of paper are lost. This technology is realized because of the shaftless drive. When the black version does not need to be converted, the machine can also be used as a general six color machine (printing spot color, fluorescent color, etc.). Although the equipment investment is large, the utilization rate is high

kba also performed the black version conversion technology of its five printing units on drupa. This method, which can complete the black conversion of pictures and texts in an instant, shows that the same effect can be achieved with an investment of less than 6 color decks

in 2004, it acquired American Gauss company of Heidelberg rubber tire department and announced its full-color printing non-stop conversion technology on print 05. Gauss calls it "automatic transfer", which is realized on an eight color machine equipped with two yellow edition units, two magenta edition units, two green edition units and two Black Edition units

when the odd number unit is in the printing process, the even number unit will replace the printing plate. When the odd number unit printing is completed, the drum is off press, and the even number machine silk drum is pressed at the same time for non-stop conversion printing. This is only when equipped with seamless rollers (when stopping operation, the rubber blanket rollers can be very separated from each other: the technology that can only be realized by Sunday prt-l is that the rubber rollers of general rubber tyred machines cannot be very separated from each other.

3 variable size rubber tyred on the stage

the work of commercial rubber tyred machines can be roughly divided into two categories, namely, b-specification paper prints based on advertising leaflets and a-specification paper prints based on mailing lists. However, in fact, I often appear {there are many specifications for printing, but there is no specification a printing (mail order catalogue) The rubber tyred machine that can print and cause A-size paper has nothing to do. Can one equipment be used to complete the production of two specifications of products? 7 many printing houses have expressed this expectation

this expected variable size rubber tyred machine has been released by Mitsubishi child labor. This rubber tyred machine, called diamond i6max-v, puts a light roller on the shaft and realizes the size conversion by changing the diameter of the roller. Its circumferential dimension varies from 546mm to 625mm, just from half cut B to full cut a. The photoelectric encoder will have pulse signal output

the realization of variable size printing on the rubber wheel is largely due to the shaftless drive technology. The upper and lower plate cylinder and rubber can effectively avoid oil leakage and seepage; There are 4 rollers in total. Both are driven by independent motors. The upper and lower ink roller systems are also driven by independent motors. One unit is equipped with 6 servo electric sheds

corresponding to different sizes of rollers, the position of the ink roller also needs to be adjusted by the phase Gallery, which can be automatically adjusted by the eccentric mechanism. The printing plate is tightly wrapped on the printing plate cylinder sleeve and fixed with adhesive. The aluminum based printing plate can be recycled (through the developed on-board printing plate regeneration system RPS)

the RPS system is a device that sprays photosensitive resin polymer on the drum, scans the image through laser exposure and performs automatic development. After printing, the unused images are cleaned, stripped, coated with polymer, scanned and developed, and can be reused for 20 times. This machine can be called "quasi DL printing machine". The machine was exhibited on drupa 04, and it was made into a 4-color machine in August, 2005. Mitsubishi Heavy Industries held a customer and media reception and conducted a public demonstration of size change. The videotape of the live demonstration was introduced to audiences from all over the world on print 05

4 progress in high speed, width and automation

the high-speed progress of rubber tyred machine is eye popping. Now, the rubber tyred machine (15m/s) with the same speed as the gravure wheel machine has come out. Cold graphic company of the United States, which has the first number of rubber tyred machines installed in the world, has been committed to the wide range of rubber tyred machines for a long time and has achieved many results. The usual rubber wheel printing format is 2x4 (2 pages around the drum × Axial 4 pages), each turn will get a positive and negative I6 page product, which is the so-called 2x4 rubber wheel. Coht graphic has developed a 2x6 glue machine with 1.5 times the width since 1994. In particular, recently, some enterprises have introduced 2x8 rubber tires with a width of 2 times. The manufacturers are Manroland and Gauss. The width is 72 inches (1824mm), which is twice the width of ordinary rubber tires. The production efficiency is also 2 times, and the printing cost is greatly reduced

At a technical seminar, Mr. mark pop of cold graphic company explained the following matters that must be considered in the introduction of such a wide rubber tyred machine:

in order to ensure that the produced Folding stickers can be transported quickly, enough space should be ensured:

to ensure the stability of color: to ensure the registration accuracy within the whole paper width:

according to the page structure different from the previous, Determine the corresponding printing production system

when the employer provides paper, it is necessary to ask him to prepare paper of different widths. Mr. mark pop pointed out that due to the above problems, it was reported that at the beginning of the introduction of 2~8 width rubber turbine, only 65% of the equipment could be used at full capacity. In order to make the introduction of wide rubber tyred machine successful, many obstacles and difficulties must be overcome, but once successful, it will be another Xintiandi

in addition to widening, the purpose of improving efficiency can also be achieved through large-diameter rollers. By increasing the drum diameter of ejj version by 1 times, higher speed can be achieved, and the number of page numbers is twice that of the original, so as to improve the efficiency of the binding process. Gauss exhibited the rubber tyred machine sun-d with three times the width and double the diameter of the drum on print 05. The main performance is that during the loading process, a lot of viewers were surprised by its huge appearance

in Europe and the United States, it is generally to combine two rubber tires, stack them in a double-layer way and operate at the same time, forming a double paper path rubber tire machine with two paper rolls stacked and posted by a folding machine. Compared with a single machine, the production efficiency is inherently higher. In addition, the wide width and large-diameter rollers further increase the difference in efficiency

on the one hand, the increasingly complete automation technology pursues high-speed, wide-ranging mass production technology, and on the other hand, under the trend of small batch printing in recent years, shortening the auxiliary time, including the change time, has become the biggest topic. In order to shorten the auxiliary time, printing machine manufacturers provide users with automatic systems such as automatic version changing devices and ink presetting devices

in the automation system, the recently introduced attention is the closed-loop color control system. The function of the system is to detect the color signal bar on the printed matter through the sensor, and calculate and mark; The difference of the output density value feeds back the correction signal to the ink key, so that the hue value is automatically maintained within the standard value range. Typical products are GMI's color quick and Quad Tech's CCS system. This kind of system can not only shorten the color matching time in the preparation process, but also keep the color tone unchanged in the printing process. Almost all the high-speed rubber tyred machines recently purchased in the United States are equipped with this system

the advantages of closed-loop color control system are:

data can be used for color management to eliminate human factors of operators. Inexperienced operators can also use it to make good use of the equipment:

it can liberate the operator from color management during the operation of the machine and concentrate on the operation and adjustment of folding machine, so as to improve the production efficiency

the system can prevent the use of excessive ink, thereby reducing the amount of ink: it can obtain the statistical proof data of color control provided to customers

store the difference data between the preset ink density and the adjusted final density. The preset data can be fed back and corrected or fed back to the prepress process according to the result

according to the measured data, we can grasp the status of ink keys or fountain devices, which is conducive to the maintenance of printing machines

5 the noticeable low-temperature drying system, as the key link to control quality and cost, is becoming the focus of attention with the improvement of the performance of the printing host. In order to prevent the quality problems caused by high-speed drying and improve the quality of printed matter, it is necessary to reduce the drying temperature

recently published a system that uses

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