A Brief Analysis of Vibration on the Printing Area in Ordinary Offset Press

2012 ◽  
Vol 591-593 ◽  
pp. 2091-2094
Author(s):  
Ming Yang ◽  
Jin Yao Li ◽  
Jia Cong Chen ◽  
Shi Jia Kong
Keyword(s):  
Product Development ◽  
Noise Reduction ◽  
Mechanical Vibration ◽  
Practical Experience ◽  
Printing Press ◽  
Print Quality ◽  
Offset Printing ◽  
The Press ◽  
Vibration Performance ◽  
Printing Presses

At the development of modern printing, vibration may course some products quality problems when increases the speed. Practical experience shows that the mechanical vibration of the offset press is an important reason to affect the print quality. Therefore, improving the vibration performance of the printing press and designing the structure of anti-vibration and noise reduction to improve the quality and speed of printing presses is an important issue in the press product development. This paper proposes some reasons and solution ideas of vibration on printing parts in ordinary offset printing machines.

Development of Modularized Inline Coating System of Multi-Color Offset Printing Press

2013 ◽  
Vol 312 ◽  
pp. 525-528
Author(s):  
Ji Bin Zhao ◽  
Cheng Nan Tong ◽  
Zhao Hua Wang ◽  
Fan Wu
Keyword(s):  
Printing Press ◽  
Coating System ◽  
Offset Printing ◽  
The Press ◽  
New Type ◽  
Printing Machine

A new type of inline coating system is designed and developed. The coating system can be mounted into printing press instead of blanket cleaner. An anilox roller and a sealed duct on the glazing oil transferring part for supplying and transferring the coating oil are introduced. A set of pressure adjusting mechanism is designed for changing the pressure between anilox roller and blanket cylinder, while a set of on-off impression mechanism is arranged to change the position of anilox roller and the on-off impression state. The press can print as normal when the coating system is dismounted. With this coating system, the press can coat prints with glazing oil. This system can be mounted in various type of printing machine. One new type of glazing technology named reverse coating can be achieved when it is mounted in multicolor press.

Statistical Consideration of Uncertainties in Bolted Joints of the Drive Train of Sheet-Fed Offset Printing Presses

2015 ◽  
Vol 807 ◽  
pp. 3-12 ◽  
Author(s):  
Nicklas Norrick
Keyword(s):  
Mechanical Model ◽  
Drive Train ◽  
Bolted Joints ◽  
System Response ◽  
Offset Printing ◽  
Worst Case ◽  
Nonlinear Mechanical ◽  
The Press ◽  
Printing Presses

This paper outlines a design process for the bolted joints of the drive train of sheet-fed offset printing presses incorporating statistical data and methods. Sheet-fed offset printing presses are driven by a continuous geared drive train along the length of the press. The bolted joints of the drive train connecting the gears to the cylinders of the press are subjected to high loads, especially during emergency stops. A nonlinear mechanical model of a printing press implemented in Matlab/Simulink is presented which is used to calculate the occurring loads. Measurements of linear and nonlinear system response are presented to support the quality of the mechanical model. The bolted joints between the main drive train gears and cylinders are designed according to current standards. Statistical information based on experimental data is considered during the application of the standardized method. Using the Monte Carlo technique, a more exact description of the joint’s strength is made possible. In this way, the maximum tolerable load for the screw connection is 16% higher than the same result from a standard worst-case calculation.

Use of confocal laser scanning microscopy and a computer model to understand ink cavitation and filamentation

TAPPI Journal ◽  
2010 ◽  
Vol 9 (10) ◽  
pp. 7-15
Author(s):  
HANNA KOIVULA ◽  
DOUGLAS BOUSFIELD ◽  
MARTTI TOIVAKKA
Keyword(s):  
Laser Scanning ◽  
Confocal Laser Scanning Microscope ◽  
Laser Scanning Microscopy ◽  
Confocal Laser Scanning ◽  
Confocal Laser ◽  
Print Quality ◽  
Length Scale ◽  
Offset Printing ◽  
Significant Difference ◽  
Printing Speed

In the offset printing process, ink film splitting has an important impact on formation of ink filaments. The filament size and its distribution influence the leveling of ink and hence affect ink setting and the print quality. However, ink filaments are difficult to image due to their short lifetime and fine length scale. Due to this difficulty, limited work has been reported on the parameters that influence filament size and methods to characterize it. We imaged ink filament remains and quantified some of their characteristics by changing printing speed, ink amount, and fountain solution type. Printed samples were prepared using a laboratory printability tester with varying ink levels and operating settings. Rhodamine B dye was incorporated into fountain solutions to aid in the detection of the filaments. The prints were then imaged with a confocal laser scanning microscope (CLSM) and images were further analyzed for their surface topography. Modeling of the pressure pulses in the printing nip was included to better understand the mechanism of filament formation and the origin of filament length scale. Printing speed and ink amount changed the size distribution of the observed filament remains. There was no significant difference between fountain solutions with or without isopropyl alcohol on the observed patterns of the filament remains.

Aeroelastic instability of paper sheet in an offset printing press

2021 ◽  
Author(s):  
Petr Šidlof ◽  
Jan Kolář ◽  
Pavel Peukert ◽  
Martin Pustka ◽  
Pavel Šidlof
Keyword(s):  
Printing Press ◽  
Paper Sheet ◽  
Offset Printing ◽  
Aeroelastic Instability

Impact of non-uniform water absorption on water-interference print mottle in offset printing

2018 ◽  
Vol 33 (1) ◽  
pp. 150-163 ◽  
Author(s):  
Sofia Thorman ◽  
Göran Ström ◽  
Patrick A. C. Gane
Keyword(s):  
Moisture Absorption ◽  
Staining Technique ◽  
Relevant Information ◽  
Print Quality ◽  
Surface Adhesion ◽  
Offset Printing ◽  
Surface Moisture ◽  
Coated Papers ◽  
Burn Out ◽  
Lift Off

Abstract Print mottle is a serious and yet common print defect in offset printing. An imbalance between the feed of fountain solution and the ability of the paper substrate to absorb and transport this water away from the surface can cause moisture/water interference problems. In the study presented here, we have investigated the uniformity of aqueous absorption and coating structure of pilot-coated papers with different types and dosages of dispersants and linked this to print mottle and uncovered areas (UCA). In earlier studies, the print quality of these papers indicated that a moderate addition of excess dispersant caused ink refusal, ink-lift-off (ink-surface adhesion failure) and water-interference mottle when printing at elevated fountain feed. In the present study, we have shown that a majority of the samples with uneven water/moisture absorption and an uneven burn-out reflectance tended to have more severe printing problems related to surface-moisture/water.An aqueous staining technique was used to characterise the absorption non-uniformities. This method has been developed previously with focus on absorption of flexographic water-based inks but can clearly give relevant information also for offset printing, when it comes to moisture/water interference mottle.

Court Jews, Printers, Book Publishing, and the Beginning of the Haskalah in the German Lands: The Life History of the Wulffian Printing Press as a Case-Study

2018 ◽  
Vol 12 (1) ◽  
pp. 1-55
Author(s):  
Gad Freudenthal
Keyword(s):  
Eighteenth Century ◽  
Life History ◽  
Book Publishing ◽  
Printing Press ◽  
Continuous Contact ◽  
The Press ◽  
History Of ◽  
Guide Of The Perplexed

Abstract This article presents the history of a printing press that operated at several places near Berlin during the first half of the eighteenth century, culminating in the epoch-making reprinting of Maimonides’ Guide of the Perplexed in 1742. The press was established in Dessau in 1694 by the court Jew Moses Wulff (1661–1729), and was run by several printers, notably the convert Israel b. Abraham (fl. 1715–1752). Using the trajectory of the Wulff press as a case study, I examine the relations between scholars, patrons of learning (especially court Jews), printers, and book publishing. The inquiry will highlight the considerable role that court Jews played in shaping the Jewish bookshelf, notably by choosing which books (reprints and original) would be funded. Surprisingly perhaps, although court Jews were in continuous contact with the environing culture, they did not usually favor the printing of non-traditional Jewish works that would favor a rapprochement.

Vibration Performance Analysis of FR Vibration Damper Using Finite Elements Method

2010 ◽  
Vol 44-47 ◽  
pp. 1268-1272 ◽  
Author(s):  
Xiao Yu Luo ◽  
Yi Sheng Zhang ◽  
Yong Ping Zheng
Keyword(s):  
Transmission Lines ◽  
Mechanical Vibration ◽  
Vibration Energy ◽  
The Finite Element Method ◽  
Vibration Damper ◽  
Harmonic Response ◽  
Overhead Transmission Lines ◽  
Design And Manufacturing ◽  
Work Done ◽  
Vibration Performance

FR vibration damper is widely used in overhead transmission lines to prevent aerolian vibration. In this paper, the vibration characteristics of the damper are analyzed. The finite element method software ANSYS was applied to investigate the modal, harmonic response and PSD of the damper based on the theory of mechanical vibration and dynamic analysis. The results prove that the FR vibration damper performs well in consuming the vibration energy of the transmission lines. Work done in this paper provides a new way based on numerical simulation in design and manufacturing of vibration damper, and has laid a foundation for further study of vibration damper.

Printability Analysis of Compostable Films by Flexographic Water Based Ink

2020 ◽  
Vol 843 ◽  
pp. 26-32
Author(s):  
Aran Hansuebsai ◽  
Samatcha Nawakitwong
Keyword(s):  
Surface Roughness ◽  
Quality Parameters ◽  
Image Resolution ◽  
Printing Press ◽  
Print Quality ◽  
Tone Reproduction ◽  
Water Based ◽  
Flexographic Printing ◽  
Set Up ◽  
Printing Speed

This research analyzed the printability of compostable films commercialized in the Thai market such as PLA/PBAT and PBAT/starch; and to comply with EN 13432 standard by using flexographic water based ink. A narrow web flexographic printing press was set up and opperated. Print quality parameters such as optical density, tone reproduction, print contrast and print uniformity were investigated. Results showed that these compostable films were hydrophobic in nature, in combination with fracture and voids of substrates’ surface. Even the substrates could be printed relatively well but showed poor ink adhesion. Surface treatment, therefore, was necessary, but having limitation. Anilox line screen 700 lpi and printing speed at 30 m/min were preferable to achieve the optimum tone reproduction and print contrast. This was based on the image resolution of 133 lpi and corona dosage at 500 watt-min/m2. Images of printed samples from SEM and SPM indicated that the fracture surface and void of films could lead to decrease their printability. It was found that starch blend gave better results as being a filler of the surface roughness of the substrate..

scholarly journals Development of mathematical models of print quality by Box-Wilson

2021 ◽  
Vol 304 ◽  
pp. 03023
Author(s):  
Ulbosin Eshbaev ◽  
Akbarjon Nishonov ◽  
Aziz Saodatov
Keyword(s):  
Objective Assessment ◽  
Color Perception ◽  
Paint Layer ◽  
Synthetic Polymers ◽  
Optimal Choice ◽  
Print Quality ◽  
Offset Printing ◽  
Before And After ◽  
Static Modeling ◽  
Printed Materials

The transfer coefficient of ink to the printed material was determined by comparing the mass of the printed material before and after printing. The specifics of the interaction of the printed surface with the surface of the paint layer and the influence of technological factors on the graphic distortion of the image when printing on paper also affect the gradation characteristic of the image. This article states about static modeling, preliminary analysis of the color perception of offset printing on papers including synthetic polymers. On the basis of the model of color perception obtained as a result of research in offset printing on printed materials, the optimal choice is developed, which allows to make an objective assessment and predict the color perception of the printed materials.

scholarly journals Analysis of Printing Pressure Using Density Measurements of Printed Ink.

2019 ◽  
Vol 11 (01) ◽  
pp. 39-46
Author(s):  
Ramesh R Dendge
Keyword(s):  
Pressure Variation ◽  
Print Quality ◽  
Offset Printing ◽  
Qualitative Information ◽  
Density Measurements ◽  
Covering Material ◽  
Uncoated Paper ◽  
Materials Used ◽  
Printing Machine ◽  
Left Middle

In process-color lithographic sheet-fed offset printing the uniformity of printing pressure is critical in achieving consistent print quality. The variations in printing pressure at blanket and impression cylinder nip affect the resultant print density of process colors. The variations in printing pressure are observed not only within the print run but also in the print area of the sheet. The printing pressure is the function of machine engineering, blanket cylinder covering material, substrate, and thickness of image carrier, packing materials used in packing of blanket and plate cylinder. Many printers, even today, use a feeler gauge to judge the level of printing pressure at two or three places along with the blanket and impression cylinder nip. The conventional feeler gauge method yields qualitative information and considers a very smaller portion of the print area. In this experimental work, the densitometry is used to devise an alternative subjective method to give information about the levels of printing pressure across the print area. The image equalling print area is divided into uniformly spaced small patches and one thousand sheets uncoated paper are printed with cyan color on large format offset printing machine. Three sheets, 101th, 501th, and 901th, representing the start, middle and the end of the print run are selected. Out of each identified sheets, three patches are selected from left middle and right columns giving a total nine locations from across the print area. The reflection densities, of nine cyan patches uniformly covering the print area, are measured using electronic densitometer for each of the sheets and tabulated. This approach, involving statistics, is aimed at providing a quantitative tool to analyze printing pressure variation across the print area and within the print run.

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