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Highlights • scanner path utilized as a manipulatable variable in paper machine cross-directional control. • faster response to load disturbances. • estimation of process noise and basis weight estimate uncertainty based on web-wide transmittance measurement. • adaptive model between transmittance and basis weight. ABSTRACT The cross-directional (CD) basis weight control on paper machines is improved by optimizing the path of the scanning measurement. The optimal path results from an LQG problem and depends on how the uncertainty of the present estimate of the basis weight and the intensity of process noise vary in CD. These factors are assessed by how accurately the CD basis weight estimate predicts the measured optical transmittance with a linear adaptive model on synchronized basis weight and transmittance data. Simulations on optimized scanner path in disturbance scenarios are presented, and the practical implementation of scanner control is discussed. [ABSTRACT FROM AUTHOR]

The converter transformer epoxy impregnated paper bushing is a multi-media electrical equipment, and the main materials include the internal conductor, the external conductor, transformer oil, SF6 gas, the air inside internal conductor, the main insulation material epoxy impregnated paper, sheath, and fittings. In actual operating, the converter transformer bushing is undertaken by the harmonic current with large number of high harmonics and the temperature distribution of the epoxy impregnated paper converter transformer bushings under actual current waveform needs to be researched. What's more, the temperature distribution of the epoxy impregnated paper converter transformer bushings is affected by several factors and to provide basis for the optimization of bushings it's necessary to research about the impact of these factors on the temperature distribution of the epoxy impregnated paper converter transformer bushings. In this paper, on the basis of our previous paper [8], the 3-D temperature distribution of the 400 kV epoxy impregnated paper converter transformer bushing under actual current waveform with large number of harmonics has been simulated by using the computational fluid dynamics (CFD) and finite element method (FEM) analysis. The temperature distribution regularity of the 400 kV converter transformer bushing under different influencing factors has been computed and analyzed. The dissipation structure of the bushing has been optimized and the DC steady-state electric field distribution of the 400 kV converter transformer bushing has been obtained considering the temperature gradient in epoxy impregnated paper. [ABSTRACT FROM PUBLISHER]

The article reports on the performance of a paper machine dynamic model. According to the author, dynamic models of paper machines that have the capability to calculate the performance of various paper machines are fast becoming significant assets not only to the paper industry but to the research community as well. The author cites the evaluation made on a simulator package for modeling the wet-end of a pilot paper machine. For comparison, the data gathered following the operation of a pilot-scale paper machine and the data produced by the model were used.

In cooperation with the world’s second largest manufacturer of beverage cartons (SIG Combibloc®) for liquid foodstuffs an innovative off-take for neutralisation of reactive gas in a paper laminating machine was constructed. A great challenge during engineering work was ensuring a high concentration of the reactive gas where needed and at the same time minimising work place impact in a machine basically without housing. Preliminary 2D-models of the machine geometry proved to be insufficient in describing all the governing flow phenomena. A simplified 3D-geometry containing all important parts of the complex machinery was necessary for accurate predictions. It was found that the driving force of air movement and transport of reactive gas (which acts as an adhesive agent) from the reaction zone in the interior of the laminating machine to the outside is a boundary flow caused by the rapid movement of carton material and rotating cylinders. A physically correct simulation result of the boundary flow is a premise for correct prediction of air flow in and around the machinery. Lacking experimental data (due to an inaccessible geometry) a worst case scenario was constructed by generating a grid and using turbulence models that maximised mass transport in the boundary layer region and thus emission of (tracer)gas from the machine. CFD simulations were done using the geometry preprocessor Gambit, and the finite volume solver Fluent. The results of the analysis of the emission paths from the machine were surprising and led to the construction of an effective off-take relatively far away from the emission source. The chosen position ensures low disturbance of highly sensitive flow patterns inside the machine and diffusive mixing, dilution and contamination of the surroundings. The effect of the new off-take is an immediate and significant rise in air quality in the vicinity of the laminating machine and ensures maximum allowed concentration in the plant area. The product quality furthermore is uncompromised by the working off-take which was another important goal of this work. [Copyright &y& Elsevier]

The article reports on new or revised technical information papers and test methods from the Technical Association for the Pulp, Paper and Converting Industry. These include the following: pilot paper machines; guide to the use of stainless steel pipe specifications; fiber length of pulp by classification; test conditions for fiber glass mat test methods and sample location for fiber glass mat sheets.

The printing plate and its characteristics in the conventional printing techniques have a significant impact on print quality and image appearance. In screen printing, a weave of screen mesh i.e. a number of threads per cm, is the most important characteristic of the printing plate, hence the most relevant factor which defines printing quality. Print quality itself is a complex term that includes desired colour reproduction and satisfactory reproduction of image elements. In this paper focus was centred upon the reproduction of text and basic image elements (lines and dot structure) when printing on non-absorbent and absorbent substrates with different screen thread counts. The image element analysis led to the conclusion that using mesh with higher thread count does not significantly improve the reproduction of image elements. However, it is a very important parameter for text reproduction since low thread count may result in poor readability. [ABSTRACT FROM AUTHOR]

The article offers information on the Perkins Bacon printing records' recovery that offered an opportunity for reappraisal and reconsideration of the printers work. This type of work prevailed at the time the first plates of the public issue were settled and printed. An "N" denoted against the weekly sheet numbers for the printers at press was found through detailed examination of the wages records.

The article presents a roundtable discussion which explores how paper mills can work with machinery and fabric suppliers to manage machine clothing changes during rebuilds. One of the participants discusses some levels of involvement that a mill can pursue to ensure that fabrics are correctly selected for a rebuild. Another participant explores some factors to consider regarding the rebuild of the forming section and clothing application. They also explain the effect of paper machines conversions to higher value grades on forming machinery and fabrics.

The article focuses on the presentation of digital platesetting or plates by the proponents of thermal technology at Ipex in Birmingham, England. Agfa Corp. showed its three new Energy plates that will replace the Thermostar 970 which include the Energy Marathon and the Energy Elite. The company has also demonstrated its chemistry-free violet polymer plate for the first time. Basysprint GmbH has showed its well-known flatbed platesetters for conventional ultraviolet-sensitive diazo plates. Escher Grad and ECRM Imaging Systems has offered two new models for commercial printers.

Reports on Paper Converting Machine Co.'s plan to close its Reber Street plant in Green Bay, Wisconsin on June 2004. Number of jobs eliminated; Production of paper converting machines by the plant.

The article features processless print plates from Fujifilm and Kodak Co. in the United States. The excess emulsion is removed during startup in these processless plates. Fujifilm's processless plates are the thermal Brillia Pro-T and the Brillia Pro-V. On the other hand, Kodak Thermal Direct is a negative thermal plate with aluminum substrate and polymer layer. These plates represents the first time plates have been offered on which the exposed image is almost invisible before the start of printing. These plates also offer advantages in production due to the absence of chemical development and their high stability in processing.

The article reports on the unveiling of Newspaper 2.0 program by Kodak Co. at the IfraExpo in Vienna, Austria. According to H. Jack Knadjian, vice president publishing market segment for Kodak, the program will help newspapers better compete in the evolving media market by utilizing the speed and quality advantages of digital technology. The program influenced Kodak and MAN Roland Inc. to adapt the Kodak Versamark DP6240 printer and the Kodak's Versamark VX5000 Printing System with inline finishing from Hunkeler AG of Switzerland. The Versamark DP6240 printer can print up to 3,000 feet per minute on a newspaper press to add variable text, bar codes and images. Furthermore, the alliance is projected to better serve a mobile and geographically dispersed consumer market.

In this article, the author examines large-format, flatbed inkjet printers, a market that did not exist four years ago, and discusses the suppliers who emerged at the conference in 2004. The flatbed market, where large sheets of board or other solid materials for markets, such as point of sale and displays, are printed began on Easter 2001, when Inca Digital launched its Eagle printer. The emphasis now is on speed, as quality is sufficient for the purpose, and newer machines, such as Inca's Columbia, have accelerated the speed of imaging.

An introduction to the journal is presented in which the editor discusses articles on abstracts of paper published in the journal in 2009, products and services guides, and subject index.

Presents information on web handling resources and courses offered by the Technical Association of the Pulp and Paper Industry in 2005. Offer of courses on web handling and converting and on winding operations; Information on the book "The Mechanics of Web Handling," by David R. Roisum; Fees, venue and registration information on a tutorial on corrugated converting machinery maintenance.

The article presents a case of contact allergy arising due to acrylate monomer in a printing plate. Several authors have described contact sensitization to various acrylic monomers in ultraviolet curing printing inks and plates. In the present case the main output of the plant where the plates are used is printed forms. The plate in question has been in use since October 1978. The company uses about 12,000 plates a year. The patient in question is a 34-year-old woman without previous skin trouble. Since spring 1980 she has had recurrent eczema first on fingers and hands and later also on the face. The eczema healed when she was away from work and recurred when she returned to work.

The 3040 Engineering Copier is a wide-format printer equipped with a two-media roll supply system. Features: Switches to the second supply roll immediately after the first is depleted, avoiding any […]

Stratasys is making a limited number of its Genisys 3D printers available at a special price of $36,900. Each system includes a Genisys 3D printer, AutoGen network software license, full […]