Transfer Roller Research Articles

Isı Transfer Silindirlerinde Halka Akış Kanalı Geometrisinin Isıl Performansa Etkisinin Sayısal Olarak İncelenmesi

In this study, heat transfer behavior in a rotating annular flow field is investigated via computational fluid dynamics. The annular flow field subject to the study is the heat transfer cylinders (rolls) widely used in different fields of industry. The heating or cooling function in heat transfer rollers is provided by the work fluid moving in the flow area in the annular section under the roller surface. The behavior of the working fluid conditioned by the channel geometry is directly related to the thermal performance of the heat transfer roller. The purpose of this study is to investigate the effect of the geometric structure of the channels through which the work fluid moves on the heat transfer behavior. For this purpose, the types of work fluid working channels included in the heat transfer rollers, which are frequently used in industrial applications, were examined and models of different types were determined and modeled numerically. In the study, the roller rotation speed was kept constant and three different fluid flow rates were examined. The results of the study were examined in terms of total heat transfer, roller surface temperature distribution, the amount of heat absorbed from the produced material and the hydraulic pressure drop of the fluid. As a result of the study, it was seen that the channel geometries that hydrodynamically condition the working fluid have a significant effect on the heat transfer behavior. The thermal performances of roller models with different fluid channel structures under varying operating conditions have been comparatively examined and it has been observed that the model with decreasing spiral channels can benefit from a uniform surface temperature.

Maintenance System of Universal Goss Printing Machine based on failure data using RCM and RCS method

OverBased on RCM analysis for each critical subsystem obtained interval preventive maintenance for transfer roller 127.60 hours, Ink fountain roller 24.45 hours, ink form roller 29.23 hours respectively, and the wash-up device is no scheduled maintenance. For spare parts inventory strategies the result using RCS method are: transfer roller104 units, ink fountain roller requires 32 units, ink form roller 36 units and are holding spare policy required, and a wash-up device no holding spare parts.
 
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Maintenance System of Universal Goss Printing Machine based on failure data using RCM and RCS method

Over time a machine will get experience a decrease in reliability, causing the engine to be damaged at the time of operation, thus disrupting the production line. To maintain a machine remains reliable then a good maintenance system is required. In this research, we will use Reliability Centered Maintenance (RCM) and Reliability Centered Spare (RCS) analysis on the critical system of Goss Universal printing machine based on engine failure data. The result of RCM analysis obtained the optimal preventive maintenance schedule and the type of treatment, while based on the RCS analysis obtained spare part needs following the maintenance schedule. With the result of this analysis, is expected where the machine will keep good and will continue to operate without a sudden breakdown under the production schedule's need. Based on RCM analysis for each critical subsystem obtained interval preventive maintenance for transfer roller 127.60 hours, Ink fountain roller 24.45 hours, ink form roller 29.23 hours respectively, and the wash-up device is no scheduled maintenance. For spare parts inventory strategies the result using RCS method are: transfer roller104 units, ink fountain roller requires 32 units, ink form roller 36 units and are holding spare policy required, and a wash-up device no holding spare parts.
 Keywords— Failure data, Maintenance System, RCM, RCS

Optimization of Break Draft, Pin Spacer and Rubber Cots Hardness to Enhance the Quality of Ring Spun Yarn Using Factorial Design

The aim of the present work is to optimize the drafting parameters for ring spinning by using full factorial (23) experimental design. Three drafting parameters of ring spinning each at two levels were chosen for this study. These technological parameters were break draft, size of pin spacer and hardness of rubber cots. It was found from statistical analysis that pin spacer size has a significant effect on yarn unevenness (U %), imperfection index (IPI), hairiness (H) and yarn strength (CLSP) compared to the other two chosen factors. These yarn quality parameters were improved by increasing the spacer size. The increase in spacer size reduces the cohesive forces among the fibers during drafting. The pin between the cradle and the top front roller transfer the individual fibers from the drafted fiber assembly to the spinning triangle without any stretching or accumulation. This yields a more integrated structure and the quality of yarn is improved.

Study on design of temperature - dependence of sublimation transfer roller

Sublimation trasnfer machine's hot roller, a compression type electronic heater, is made of ceramic core which is wrapped with nickel-chromium alloy heater. This roller is insulated with magnesium oxide. When the power is on, the heat is generated. Heat transfers are from high temperature area to low temperature area, and it causes the non-uniform temperature surface and the roller surface distorsion. Such effects always increase with larger diameter of the roller and longer the roller. In order to predict the sublimation transfer machine's roller temperature distribution and validate it, we construct the roller's 3D temperature model and use ANSYS steady state heat transfer analysis module to calculate the power dissipation and simulate it. Final data shall help us to design sublimation transfer machines' roller.

Numerical modeling of the undertow structure and sandbar migration in the surfzone

A process-based 3D numerical model for surfzone hydrodynamics and beach evolution was established. Comparisons between the experimental data and model results proved that the model could effectively describe the hydrodynamics, sediment transport feature and sandbar migration process in the surfzone with satisfactory precision. A series of numerical simulations on the wave breaking and shoaling up to a barred beach were carried out based on the model system. Analyzed from the model results, the wave-induced current system in the surfzone consists of two major processes, which are the phase-averaged undertow caused by wave breaking and the net drift caused by both of the nonlinear wave motion and surface roller effect. When storm waves come to the barred beach, the strong offshore undertow along the beach suppresses the onshore net drift, making the initial sandbar migrate to the seaside. Under the condition of calm wave environment, both the undertow and net drift flow to the shoreline at the offshore side of the sandbar, and then push the initial sandbar to the shoreline. The consideration of surface roller has significant impact on the modeling results of the sandbar migration. As the roller transfer rate increases, the sandbar moves onshore especially under the storm wave condition.

A study on the triboelectric charging of display glass during the roller transfer process–modeling and characterization

Glass substrates for displays are insulating materials capable of generating and maintaining high levels of triboelectric charges posing a risk of electrostatic discharge (ESD) damage to electronic display components. In this work, an apparatus for triboelectric charging characterization of display glass during the roller transfer process was designed and fabricated. In order to establish the reliability of the characterization, the triboelectric charge and the electrostatic potential distribution measurement system was automated. The preconditioning process of the glass and the rollers was also addressed. In order to analyze the measurements' results, a multiphysics model that considered both electrical and mechanical properties was proposed. The test parameters that were expected to affect the triboelectric charging characteristics are defined and discussed, as well as some of the characterization results such as the effects of acceleration/deceleration and maximum velocity, relative humidity and moisture on the glass and the rollers, and the conductivity of the rollers. The peak-to-peak deviation of the de-embedded triboelectric charges, due to a steady-state velocity period with different combinations of acceleration/deceleration and maximum velocities, was 14.2%. The triboelectric charges increased as the relative humidity increased from 30% to 50% with the same temperature. They also increased when the insulating rollers were replaced with dissipative rollers.

Predicting Paper Wrinkles in Fusing process of Laser Printers using dynamic FEA

One of the persistent problems in the development of laser printer is paper wrinkles in fusing process. Factors affecting this problem are due to internal factors of fuser and layout factors between transfer roller and fuser. This paper suggests modeling methods to simulate mechanical characteristics to predict the possibility of paper wrinkle in fuser by change of layout parameter. Layout parameters are relative position and angle of fuser about transfer roller and inlet guide position from fuser nip. Through 3D dynamic simulation, it calculates the compressive plastic strain of the paper passing through the fuser unit, and wrinkle criteria were set up on the basis of jig experiments. The analysis method can be extended to a variety of practical paper wrinkle problems, and the scalability is considered high. The usefulness of these methods was validated by the comparison with experimental results.

Determination of Parameters of Roller of Wave Transmission with Intermediate Rolling Bodies with Hollow Shaft for Geokhod

The paper presents a calculation of the roller minimum length based on the contact stresses at work on the transfer roller surface and separator.

Modeling of Temperature Distribution in Moving Webs in Roll-to-Roll Manufacturing

A heat transfer model that can predict the temperature distribution in moving flexible composite materials (webs) for various heating/cooling conditions is developed in this paper. Heat transfer processes are widely employed in roll-to-roll (R2R) machines that are used to perform processing operations, such as printing, coating, embossing, and lamination, on a moving flexible material. The goal is to efficiently transport the webs over heating/cooling rollers and ovens within such processes. One of the key controlled variables in R2R transport is web tension. When webs are heated or cooled during transport, the temperature distribution in the web causes changes in the mechanical and physical material properties and induces thermal strain. Tension behavior is affected by these changes and thermal strain. To determine thermal strain and material property changes, one requires the distribution of temperature in moving webs. A multilayer heat transfer model for composite webs is developed in this paper. Based on this model, temperature distribution in the moving web is obtained for the web transported on a heat transfer roller and in a web span between two adjacent rollers. Boundary conditions that reflect many types of heating/cooling of webs are considered and discussed. Thermal contact resistance between the moving web and heat transfer roller surfaces is considered in the derivation of the heat transfer model. Model simulations are conducted for a section of a production R2R coating and fusion process line, and temperature data from these simulations are compared with measured data obtained at key locations within the process line. In addition to determining thermal strain in moving webs, the model is valuable in the design of heating/cooling sources required to obtain a certain desired temperature at a specific location within the process line. Further, the model can be used in determining temperature dependent parameters and the selection of operating conditions such as web speed.

Preparation and Biological Characterization of Electrospun Aligned Poly(butylene carbonate) Nano-Fibers

A novel biomaterial poly (butylene carbonate) (PBC) was used to fabricate aligned nanofibresby electrospinning with a high-speed transfer roller as the receiving device. The morphology of the fibers was evaluated by scanning electron microscopy (SEM). To expand the application of the biomaterial, cold plasma treatment and induced grafting technology were applied to improve its hydrophilicity and biocompatibility. The properties of the fibers, pretreated withhelium and following grafting with gelatin,were evaluated with X-ray photoelectron spectroscopy. The cytotoxicity of the materials to Schwann cells (RSC96) was investigated. Results indicated that aligned nanofibers can be received at high rotation speed.After plasma pretreatment, the activity of the surface was improved significantly and the grafting reaction was successful. SEM observations showed that cells can grow on the fibersurface along the direction of fiberorientation after seeding with RSC96 for 3 and 5 days. Modification of the nanofibersurface with gelatin significantly increased RSC96 attachment and proliferation.

D-2-5 電子写真転写部での静電気による用紙挙動解析

At second transfer roller process in electrophotography system, paper deformation is caused by electrostatic force stronger than the rigidity of a paper, which might cause paper jam. We are studying to understand the mechanism of paper deformation by charge generated on a paper. So a numerical simulation tool is developed in order to analyze the paper deformation by the effect of transfer parameter. And also we observe paper deformation occurred by electrostatic force. The calculation results are compared with experimental results. The calculated tendency to paper deformation results shows good agreement with the experimental results.

Preparation and surface modification of electrospun aligned poly(butylene carbonate) nanofibers

In this study, aligned poly(butylene carbonate) nanofibers were fabricated by electrospinning with a high-speed transfer roller as the receiving device. Cold plasma treatment technology was applied to improve its hydrophilicity and activity to expand its application in biological materials. The morphology of the fibers was investigated with scanning electron microscopy. X-ray diffraction was used to research the impact of the rotation speed on the crystallization and orientation degree of the crystals. The tensile properties of the materials were evaluated by a universal tester. The surface properties of the fibers pretreated by Helium (He) and those grafted with gelatin were evaluated with water contact angle measurement and X-ray photoelectron spectroscopy. The experimental results indicate that the order degree of fibers, crystallinity, and orientation of the crystalline region, including the mechanical properties, all increased correspondingly with the rotation speed. After plasma pretreatment, the hydrophilicity was improved significantly, and the grafting reaction was realized successfully. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Investigations of Charge Migration and Charge Trapping in Fatigued Organic Photoconductors

This article presents the experimental photodischarge kinetics of electrostatically fatigued dual-layer organic photoconductors characterized by an electrophotographic incremental charging technique that reveals the differences in the photoconductor charging profiles. During normal operation, 15% of the holes that migrate to the surface after photodischarge are not neutralized by the negative surface ions. The accumulation of these lingering surface charges (charge transport material radical cations) manifests itself as defects in half-tone images, as either missing or reduced size dots or lines. In the presence of corona gases, these surface holes oxidize and reduce the energy barrier for hole injection from a positively charged surface, e.g., contact with a transfer roller. These injected holes accumulate near the charge generation layer and require twice the amount of negative charge to attain the same surface potential as that of a new organic photoconductor (OPC) drum. The damaged depth of this injection region extends to about 50 nm into the OPC surface and is easily removed by the printer’s abrasion mechanisms (e.g., cleaning blade, toner, paper).

Dependence of Electrostatic Field Strength on Image Transfer Roller Dimensions in a Toner Transfer Region

Using an expansion of electrostatic potential in terms of partial solutions of the Poisson equations, a distribution of electrostatic field strength in a two-dimensional (2D) toner transfer system region between the toner and the paper has been calculated. The results have been obtained for a system in which photoreceptor and toner transfer element is a roller with a finite radius. In these calculations, the photoreceptor, the toner, and the paper have been characterized by the values of their thickness and dielectric permittivity. Results have been obtained when the transfer element is flat and when it is shaped as a roller with a finite radius. It is concluded that the one-dimensional (1D) approximation cannot be applied to calculate the electric field when the roller radius is close to or less than the radius of the cylinder-shaped photoreceptor. The limits of applicability of the dielectric thickness have been demonstrated.

Effect of transfer roller surface profile on discharge mark

In this report, we discuss the reason why transfer roller surface profile affects the discharge mark, and propose a new roller model for numerical simulation. Our observation has revealed that the discharge mark depends on the surface profile of transfer rollers, the conventional foam roller, smooth roller which has a smooth surface made of high polymer materials upon a foam roller, and the rough sanding roller which has the sanded surface of smooth roller. To make its dependence clear, we experimented with the electric charge distribution at transfer nip area focusing on the surface profile of the roller. Then, we build “Surface layer model” consisting of base-layer and surface-layer. The numerical simulation of electric field using this model made it clear that roller surface profile affects the discharge mark.

Technical Evolution of Ceramic Tile Digital Decoration

The first digital systems to appear in the traditional decoration of ceramic tiles were for the manufacture of photolithographs, screen printing screens, and rollers. However, since these systems do not allow direct digital decoration of the ceramic tile, they are not very versatile and constrain productivity.The formulation of inks with soluble and vitrifiable stains enabled inkjet printing technology to be introduced into ceramic tile decoration. The incorporation of milled inorganic pigments into the inks then broadened the available colour palette. The colloidal instability of these inks and the own constraints of the printing heads made it necessary to reduce the particle size of the pigments used, thus limiting colour saturation.In order to overcome this technological challenge, pigments with larger particle sizes need to be used, making it necessary to introduce other digital decoration techniques, such as xerography.The adaptation of this technique to ceramic tile decoration entails the development of ceramic toners and the adjustment of the printing machines. A system has been developed that is able to print ceramic tiles by contact, which has required adjusting the mechanical and electrical properties of the transfer roller.

Temperature control of transfer roller’s bearing based on finite element analysis

After a heat preservation cover is installed on the main rolling line, the heat dissipation environment of the transfer roller working on the heat preservation cover is changed. To ensure the normal production, a reasonable working jet capacity of the roller neck is derived. First, a globe model of the transfer roller is built for finite element analysis. Second, the sub-model of the fixed end bearing is built and the boundary condition of the sub-model is supplied by the results of the globe model. The analysis result of the sub-model shows that the temperature of the transfer roller bearing exceeds 85°C a rolling periodicity later. With finite element analysis, the heat flux is obtained and the minimum working jet capacity is derived.

Key Polyurethane Attributes & Their Effect on Electro Photographic Roller Life & Performance

This paper will cover in details, 1) What types of polyurethane should be considered for Charge roller, Transfer roller, Developer roller & Paper transport feed roller application. 2) Important polyurethane properties consideration based on roller application. 3) Effects of PU properties & its impact on performance. 4) Effect of electrical properties on different PU structure – impact on roller life & performance.

Pad Transfer System for Small Color Laser Printer

Canon has newly developed a transfer system that utilizes a pad as a transfer process, and adopted it on a small color laser printer, LBP5050. During transfer process, it is necessary to provide an enough transfer electric field to toner as regulating scattering caused by pre-transfer and discharge marks by separating discharge. This report clarifies that, with the conventional roller transfer system, it is necessary to minimize an upstream tension nip width, and maximize a physical nip width and downstream tension nip width in order to achieve an optimal condition. Also, by comparing the pad transfer system and the roller transfer system in their abilities to transfer, this report estimates problems that could occur in minimizing the size of devices with the roller transfer system and concludes, with the use of pad transfer system, those problems can easily be resolved. Ultimately, the pad transfer system is superior in its compactness and image quality to the roller transfer system.