Press Temperature Research Articles

A study on fire risk and its mitigation in gravure printing press

The gravure printing process is widely utilized for large-scale, high-quality, multi-colored printing tasks executed at high press speeds. This includes a diverse range of products such as art books, greeting cards, currency, stamps, wallpaper, magazines, and more. This thesis addresses the fire risks associated with gravure printing, acknowledging the use of highly flammable materials and the potential for static charge-related incidents. Despite its prevalence, there is limited research on fire prevention and control in gravure printing. The study employs field observations, stakeholder interviews, and an extensive review of literature on fire risk and control in printing press operations in India. It analyzes the causes of fires using the fire triangle model, emphasizing the role of heat, combustible materials, and oxygen in fire incidents within the printing press environment. The thesis categorizes preventive measures into fire prevention and fire suppression actions, focusing on reducing fire load, static charge mitigation, and implementing firefighting systems. It observes that poor housekeeping, lack of awareness, and inadequate emergency control plans contribute significantly to fire hazards in press facilities. Additionally, the research identifies key factors such as high press temperatures, low humidity, improper storage, and inadequacies in firefighting systems as potential causes of fires. It emphasizes the need for optimal environmental conditions, proper storage practices, and effective firefighting infrastructure within press facilities. The study concludes with comprehensive guidelines for loss prevention and control, including management programs, housekeeping, operator training, pre-emergency planning, preventive maintenance, and plant security. It also addresses safety measures specific to gravure printing presses, such as automatic sprinkler systems, fire hydrant system, carbon dioxide flooding systems, and portable fire extinguishers. In summary, this thesis provides valuable insights into the multifaceted nature of fire risks in gravure printing presses and recommends a holistic approach for effective fire prevention and control.

Influence of rice straw and wood fiber combination on physical and mechanical properties of rice straw pulverized composite board

The production of particleboards from various kinds of ligno cellulosic materials are successful on commercial scale in various parts of the country. However, much success is not seen in use of crop residues for particleboards. Rice straw and wheat straw are one such materials that are abundantly available in India that can be used to produce particleboard. The present work investigated the effect of Rice straw particles and wood fibers combination on physical and mechanical properties of the composite board. The pulverized rice straw composite boards were produced with three different composition of rice straw material (100 %, 70 %, 50 %) and wood Fibers (0 %, 30 %, 50 %). Melamine Urea Formaldehyde (MUF), Phenol Cardanol Formaldehyde (PCF), Blocked Isocyanate resin combined with PCF (BPCF), Blocked Isocyanate combined with Urea Melamine Formaldehyde (BUMF) and Blocked Isocyanate combined with PF (BPF) resins were synthesized. The resin system (10%,12%,14%) with requisite additive was admixed with rice straw and wood fibers. According to the resin system employed, the hot press temperature, specific pressure and curing time were worked out for compression of the boards. The boards were produced with 780 - 850 kg/m3 nominal density and prior to testing, the test specimens were exposed to an atmosphere maintained at a relative humidity of 65 ± 5 percent and at a temperature of 27 ± 2 °C until their masses are nearly constant. The boards made were subjected for evaluation of physical and mechanical properties according to IS 3087. It was found that the Rice Straw particles with Wood Fibers of 50-50 combination bonded with PCF and also with MUF adhesive of 12 % resin solids confirms to the requirement of physical and mechanical properties as per IS 3087 particleboards of wood and other lignocellulosic materials (medium density) for general purposes Specification. Comparison with resin for hybrid boards of rice straw particles with wood fiber, BPCF has shown excellent properties than BPF and BUMF. The study indicated that increasing the percentage replacement of wood fibers with rice straw particles by more than 50 % decreased the internal bond strength. It can be concluded that rice straw pulverized particleboard can be successfully made with the combination of 30 % - 50 % wood fibers using PCF resin or BPCF resin.

Hot Compression of Calcium Chloride and Sodium Carbonate Modifies Wood for Tsoongiodendron odorum

To enhance the density and properties of Tsoongiodendron odorum and expand its range of applications, the physical and mechanical characteristics, such as density and hardness, were investigated after impregnating a solution of sodium carbonate and calcium chloride to generate calcium carbonate filler within the wood, followed by thermal compression. The results showed that the surface density of wood was significantly increased by 86.4%. The rate of weight gain gradually increased with sodium carbonate concentration, reaching a maximum of 55.67%. Hardness increased by 85.3%. The optimal treatment process is a compression rate of 5%, a pressing temperature of 170 °C, and a hot-pressing time of 30 min. Microscopic observations revealed that the calcium carbonate was predominantly distributed on the surfaces of wood, while the surface cells exhibited deformation upon compression. Conversely, the cells in the innermost region of the wood remained largely unaltered, thereby achieving a stratified compression effect. Impregnation and compression treatment increases the hardness and bending strength of Tsoongiodendron odorum, but spring-back may occur, and the dimensional stability measures necessitate further investigation and analysis.

Production and thermo-structural analysis of a hybridized natural fibre-based ceiling board for building applications

Canewood and palm kernel fibre (PKF) have successfully been used as filler material for producing ceiling boards, with recycled low-density polyethylene (LDPE) as the binder. This work covered three aspects which are the optimization of process and production parameters, chemical, and thermal analysis of the utilized filler material. The production parameters considered are the percentage composition of both the binder and filler material while the process parameters studied are the press temperature, pressure and time. These parameters were optimized over both physical and thermal properties of the developed ceiling board which are thermal resistivity, water absorption and thickness swell. Thermal results for both the cane wood and PKF proved to be thermally stable up to temperatures as high as 325 and 310°C, respectively. The optimized ceiling board showed a thermal resistivity, water absorption and thickness swell of 16.192 W/M.K, 4.669 and 6.594% respectively, for a production and process parameters of 15% cane wood, 10% PKF, 75% LDPE, 6 min press time, 7 bar pressure and 198°C press temperature. The produced ceiling board showed a specific heat capacity, thermal energy and heat flux of 769.23 Jkg−1K−1, 60 W and 23.07 kWm−1 respectively. The findings imply that the LDPE filler materials are appropriate for use in ceiling board applications.

Dopant dependent microstructure of hot-pressed SiGe alloys and its implications on thermoelectric properties

SiGe is a proven high temperature thermoelectric material for space application. We have investigated the role of dopants (P and B) on the densification of SiGe alloys. It was observed that on P doping there is a formation of liquidous SiP phase in the SiGe matrix during hot pressing that improves the diffusion across grain boundaries and as a result ∼98 % of theoretical density was achieved. In case of identically prepared B doped samples, the segregation of B resulted in porous microstructure and low density ∼89 %. Such a difference in microstructure resulted a figure-of-merit of ∼1.29 (at 1100K) for n-type SiGe (P doped) and ∼0.86 (at 1100K) for p-type SiGe (B doped) at a hot press temperature of 1273 K. The study suggests that in case of SiGe apart from doping the densification of materials plays a very important role in improving its thermoelectric performance.

Using Heating and Cooling Presses in Combination to Optimize the Consolidation Process of Polycarbonate-Based Unidirectional Thermoplastic Composite Tapes.

The main aim of this work was to optimize the consolidation of unidirectional fiber-reinforced thermoplastic composite tapes made of polycarbonate and carbon fibers using a heating press and a cooling press in combination. Two comprehensive studies were carried out to investigate the impact of process settings and conditions on the quality of the consolidated parts. The initial screening study provided valuable insights that informed the design of the second study, in which the experimental design was expanded and various modifications, including the implementation of a frame tool, were introduced. The second study demonstrated that the modifications in combination with a high heating press temperature and elevated heating and cooling pressures successfully achieved the desired goals: the desired thickness (2 mm), improved bonding strength (23% increase), and reduced void content (down to 4.64%) in the consolidated parts.

New particleboards for food-packaging from poplar peeling by-products using a circular economy approach

Poplar (Populus x canadenses Moench.) veneers (PWV) are a sustainable raw material traditionally used for producing food-packaging containers. However, the poplar log peeling process, to obtain veneers with a thickness of 0.8–2 mm, generates a large amount of waste, mostly consisting of bark and clippings from veneer sheets. The current work is focused on using these by-products to produce a new material, in the form of thin particleboards, that can be used for package production. The clippings from veneer sheets were dried and milled, and then sieved to obtain different particle size fractions. A bioadhesive, based on poplar bark extract combined with citric acid, was combined with the particles to produce single layer 210 mm × 210 mm x 2 mm particleboards by heat-pressing (press temperature = 160 °C, pressing time = 10 min, resin load = 10 wt%). It was possible to produce 100 % biobased particleboards in which the internal bond resistance and the moisture-resistance properties surpass the EN 312 requirements for boards type P3 for non load-bearing boards used in humid conditions, without the addition paraffin or any other additive. This work shows that the valorisation of by-products of poplar wood veneer production allows manufacturing high-performance particleboards, that can be used by the same industry to manufacture food-packaging containers. The viability of recycling used particleboards was demonstrated, yielding products with enough performance to be used in the production of new packaging products, and an alternative to the possible composting of these particleboards.

Impact of Hot Isostatic Pressing Temperature on Tensile Properties of TA15 Titanium Alloy Produced via Laser Powder Bed Fusion

TA15 titanium alloy holds great significance as a crucial material in the aerospace industry. In order to gain deeper insights into the influence of hot isostatic pressing (HIP) temperature on the tensile characteristics of materials formed through laser powder bed fusion (L-PBF), a comparative heat treatment experiment was crafted, aligning with the HIP treatment temperature settings. Specifically, the temperatures selected for this investigation were 900 °C, 940 °C, 980 °C, and 1020 °C, while the duration of the holding time was set at 2 h. Notably, the microstructure within the β phase region demonstrated distinct disparities between the HIP-treated specimens and those subjected to heat treatment. The heat-treated specimens exhibited the formation of Widmanstatten structure at 980 °C, while the metallographic structure of the HIP-treated specimens consisted of the lath α phase. In heat-treated specimens, an upward trend in temperature from 900 °C to 1020 °C led to a gradual decrease in UTS (995 MPa, 947 MPa, 886 MPa, and 892 MPa), YS (921 MPa, 865 MPa, 799 MPa, and 784 MPa). The elongation (15.7%,14.6%, and 13.3%) diminished as the temperature increased from 900 °C to 980 °C. At 1020 °C, the elongation slightly increased to 13.9%. The HIP-treated specimens showcased a declining trend in UTS (1008.5 MPa, 947 MPa, 886 MPa, and 892 MPa) and YS (939 MPa, 897.5 MPa, 839.5 MPa, and 844.5 MPa) with an increase in HIP treatment temperature from 900 °C to 980 °C, after which they experienced a slight increment upon further elevation to 1020 °C. The elongation (16%,18.3%, and 20.5%) demonstrated a remarkable improvement from 900 °C to 980 °C. At 1020 °C, the elongation decreased to 17.5%.

Performance of particleboard from fast-growing species

Kelempayan (Neolamarckia cadamba) is a fast-growing tree species that can be cultivated in Malaysia. This species has potential as an alternative resource for the Malaysian furniture and panel board industries in the coming years because of a shortage of the current frequently used raw material (rubberwood). A study on potential as particleboard was done. In accordance with Malaysian Standards (MS), this study examined MOE, MOR, IB, and thickness swelling of particleboard with particle sizes of 0.5 and 1.0 mm, densities of 600 and 700 kgm−3, resin contents of 9 and 11 %, and hot press temperatures of 155 and 165 °C. Boards from 0.5 mm particle size, 700 kgm−3 density, and 11 % resin content at 165 °C hot press temperature had the greatest mechanical performance. The boards constructed from particle size 0.5 mm with the density 600 kgm−3 presence 9 % resin and pressed using 155 °C hot press temperature showed the least amount of thickness swelling. The boards complied with the standard requirements. In general, kelempayan wood is a potential raw material for the manufacture of wood composites.

The Effect of Press Parameters on the Physical and Mechanical Properties of Cement-Bonded Particleboards Produced from Veneer Wastes

This study aims to investigate the effect of press temperature and time changes on the physical and mechanical properties of cement-bonded particleboards produced using poplar veneer wastes (Populus tremula L.). In this study, single-layer cement-bonded particleboards with a target density of 1200 kg/m3 and a size of 500 x 500 x 10 mm3 were produced using 5 different pressing parameters. The physical (moisture content, density, water absorption, and thickness swelling) and mechanical (modulus of rupture, modulus of elasticity, internal bond strength, and s screw withdrawal strength) properties of the produced boards were investigated. According to the results obtained, the changes in press time and temperature did not cause a significant change in the water absorption values, while the increase in the pressing time affected the thickness swelling values positively. While the mechanical properties increased with the increase of the pressing time, values suitable for the standard were obtained in all board groups. In addition, it was determined that the most suitable time for production was 24 hours and the temperature application did not have a significant effect on the board properties

Optimizacija parametara proizvodnje ugušćene lamelirane furnirske građe proizvedene upotrebom urea-formaldehidne smole

This research aims to optimize densified laminated veneer lumber production parameters of compression ratio, press temperature, press time, and adhesive spread rate to maximize their mechanical properties. In the manufacturing process of densified laminated veneer lumber, I-77/51 American poplar clone (Populus deltoides) veneers and urea formaldehyde adhesive are used. The results showed that the compression rate and press time had the most significant impact on the mechanical properties of densified laminated veneer lumber. The optimal production conditions were determined as follows: 38 % compression, press temperature of 170 °C, press time of (10±3) minutes, and spread rate of 150 g/m2. Modulus of rupture, modulus of elasticity, tensile shear strength, and tensile strength perpendicular to panels surface of densified laminated veneer lumbers produced under these conditions increased by 49 %, 8 %, 71 %, and 23 %, respectively, compared to the control group of laminated veneer lumber. So, it can be said that the production parameters of densified laminated veneer lumbers can be optimized safely and effectively using Taguchi method-based grey relational analysis.

Evolution Behavior of Rapidly Solidified Microstructure of a Ti-48Al-3Nb-1.5Ta Alloy Powder during Hot Isostatic Pressing

In this study, Ti-48Al-3Nb-1.5Ta powders were manufactured from cast bars by the supreme-speed plasma rotating electrode process (SS-PREP) and used to prepare hot isostatically pressed (HIPed) material at 1050–1260 °C with 150 MPa for 4 h. The phase, microstructure and mechanical performance were analyzed by XRD, SEM, electrical universal material testing machine and other methods. The results revealed that the phase constitution changed from γ phase to α2 phase and then to γ phase with the material changing from as-cast to powders and then to as-HIPed. Compared with the as-cast material, the grain size and element segregation were significantly reduced for both powders and as-HIPed. When the hot isostatic pressing (HIP) temperature was low, the genetic characteristics of the powder microstructure were evident. With the HIP temperature increasing, the homogeneity of the composition and microstructure increased, and the prior particle boundaries (PPBs) gradually disappeared. The elastic moduli of powder and as-HIPed were superior to those of as-cast, which increased with the HIP temperature increasing. The hardness of as-HIPed was lower than that of the powder. The compressive strength, compressive strain, bending strength, and tensile strength of as-HIPed were higher than those of as-cast. With an increase in the HIP temperature, the compressive strength decreased gradually, and the compressive strain first decreased and then increased.

Development of plywood bonded with a novel adhesive film made from polystyrene foam waste dissolved in D-limonene

ABSTRACT The polystyrene film as a formaldehyde-free adhesive for plywood production was developed from polystyrene foam waste (PSF) and D-limonene, extracted from orange peel waste. The influence of the weight ratio of solvent (D-limonene) to foam in the range of 1, 1.5 and 2 (w/w) on the properties of adhesive film and plywood panels was studied. In addition, the effects of pressing temperatures of 150°C, 165°C and 180°C on the properties of the plywood were investigated. The adhesive film was characterized by measuring the melt flow index, the average molecular weight of the polymers and by FTIR. The bonding quality of the adhesive films was investigated by shear strength tests. Integrated gel permeation chromatography has also shown that the average molecular weight of PSF is drastically reduced by doubling the solvent content. Shear strength and bending properties were also significantly reduced by doubling the weight ratio of solvent to foam. The mechanical properties of plywood are positively affected with increasing press temperature to 165°C. In general, plywood bonded with an adhesive film prepared with a solvent to foam weight ratio of 1 and press temperature of 165°C was fulfilled the requirement according to EN314-2 for interior use.

Stressors in a bottle: A microcosm study on phytoplankton assemblage response to extreme precipitation events under climate warming

Abstract The climatic stressors that are affecting lake ecosystems, especially phytoplankton, are projected to become more intense with continued climate change (e.g., heatwaves, precipitation events). Concerns over the combined effects that multiple, coinciding stressors can have on phytoplankton necessitates investigating the impacts of different regional climate scenarios. A microcosm study was conducted to assess the responses of a phytoplankton assemblage containing a cyanobacterium (Anabaena flos‐aquae), a green alga (Chlorella vulgaris) and a diatom (Synedra) to a northwestern European summer scenario. Eutrophic microcosms were exposed to a full‐factorial design including a press temperature treatment scenario (ambient or warm) and a pulse precipitation treatment (no runoff simulation or runoff simulation). Warming scenarios had significant effects on the phytoplankton assemblage biomass, which supports our first hypothesis (H1: higher water temperatures under eutrophic conditions will support larger phytoplankton biomasses, especially cyanobacteria). By contrast, the extreme precipitation runoff event had minimal and short‐lived effects on the microcosm assemblage. Overall, the interaction between the two climate stressors was antagonistic. In contrast with our second hypothesis (H2: nutrient additions from extreme precipitation runoff will promote more productivity in higher temperature microcosms), the precipitation runoff event was not amplified by temperature. Our results indicate that the combined effect of two climate stressors on a phytoplankton community are not necessarily synergistic or multiplicative. Our findings on antagonistic interactions between climatic stressors necessitate future studies assessing variations of intensity and duration of the climatic stressors.

Fabrication and Characterization of EVA Resins as Adhesives in Plywood.

The practical problem of free formaldehyde pollution in the plywood industry is that polyethylene films have been shown to be able to replace some urea-formaldehyde resins for wood adhesives. To broaden the variety of thermoplastic plywood, reduce the hot-press temperature, and save energy consumption, an ethylene-vinyl acetate (EVA) film was selected as a wood adhesive to manufacture a novel wood-plastic composite plywood via hot-press and secondary press processes. The effects of the hot-press and secondary press processes at different levels on the physical-mechanical properties of EVA plywood (tensile shear strength, 24 h water absorption, and immersion peel performance) were evaluated. The results showed that the properties of the resulting plywood using the EVA film as an adhesive could meet the type III plywood standard. The optimum hot-press time was 1 min/mm, the hot-press temperature was 110-120 °C, the hot-press pressure was 1 MPa, the dosage film was 163 g/m2, the secondary press time was 5 min, the secondary press pressure was 0.5 MPa, and the secondary press temperature was 25 °C. EVA plywood can be used in indoor environments.

Performance Evaluation of an Improved ANFIS Approach Using Different Algorithms to Predict the Bonding Strength of Glulam Adhered by Modified Soy Protein–MUF Resin Adhesive

Despite studies on the potential replacement of synthetic resins by bio-based adhesives such as proteins in recent years, there is still no reliable method for estimating the strength of wood products made using the combined parameters in the literature. This limitation is due to the nonlinear relationship between strength and the combined components. In the present research, the application of artificial intelligence techniques was studied to predict the bonding strength of glulam adhered by protein containing different ratios of MUF (melamine–urea–formaldehyde) resin with different F-to-U/M molar ratios at different press temperatures. For this purpose, the ANFIS artificial intelligence model was used as basic mode or combined with ant colony optimization (ACOR), particle swarm optimization (PSO), differential evaluation (DE) and genetic algorithms (GA) to develop an optimal trained model to predict the bonding strength of glulam based on experimental results. Comparison of the obtained results with the experimental results showed the ability of the above methods to estimate the bonding strength of glulam in a reliable manner. Although the basic ANFIS alone and in combination with other algorithms was not able to achieve an ideal performance prediction to estimate bonding strength, the combination of GA and ANFIS offered an excellent ability compared to the combination of other algorithms combined with ANFIS. Hence, the developed ANFIS-GA model is introduced as the best prediction technique to solve bonding strength problems of laminated products. In addition, using the developed optimal model, a precise attempt was made to show the nature of the parameters used to produce glulam and determine the optimum limit.

Comparative Analysis of ANN-MLP, ANFIS-ACOR and MLR Modeling Approaches for Estimation of Bending Strength of Glulam

Multiple linear regression (MLR), adaptive network-based fuzzy inference system–ant colony optimization algorithm hybrid (ANFIS-ACOR) and artificial neural network–multilayer perceptron (ANN-MLP) were tested to model the bending strength of Glulam (glue-laminated timber) manufactured with a plane tree (Platanus orientalis L.) wood layer adhered with different weight ratios (WR) of modified starch/urea formaldehyde (UF) adhesive containing different levels of nano-ZnO (NC) used at different levels of the press temperature (Tem) and time (Tim). According to X-ray diffraction (XRD) and stress–strain curves, some changes in the behavior of the product were seen. After selecting the best model through determining statistics such as the determination coefficient (R2) and root mean square error (RMSE), mean absolute error (MAE) and sum of squares error (SSE), the production process was optimized to obtain the highest modulus of rupture (MOR) using the Genetic Algorithm (GA) combined with MLP. It was determined that the MLP had the best accuracy in estimating the response. According to the MLP-GA hybrid, the optimum input values for obtaining the best response include: WR—49.1%, NC—3.385%, Tem—199.4 °C and Tim—19.974 min.

Carbon Black Doped Graphite Composite Bipolar Plate Compounds for Improving Conductivity

Bipolar plates are a key part of fuel cells. The optimal hot press temperature, pressure, and time were determined in this study. The press condition can directly affect the relative density, thereby improving the conductivity and mechanical property. Several carbon black doped samples were also successfully prepared on the basis of the optimized preparation method. Results show that carbon black optimized the conductivity due to the “conduction bridge”. The maximum conductivity and bending strength reached 345 S/cm and 32.5 MPa, respectively. Key words: fuel cells; bipolar plate; graphite; composite materials.

Characterization of Curing and Bonding of Wood with Adhesive Mixtures of Liquefied Wood and Hexamethylenediamine

Various crosslinking agents can be added to the formulations of natural-based adhesives for wood bonding in order to achieve better durability and higher strength of the formed joints. In the present study, the effect of hexamethylenediamine (HMDA) addition on the performance of liquefied wood (LW) adhesive for wood bonding is investigated. Differential scanning calorimetry showed the improved thermal stability and crosslinking of the LW adhesive with HMDA. The intensified presence of amide linkages (C–N bonds) was found in LW+HMDA with attenuated total reflection Fourier transform infrared spectroscopy. Analysis of the bonded joints using an automated bonding evaluation system showed that a higher press temperature resulted in stronger bonds for both types of adhesives. Moreover, the addition of HMDA to LW adhesive improved the bond strength of the joints and accelerated the crosslinking of the adhesive. However, with a tensile shear strength of (6.76 ± 2.16) N × mm−2 (for LW) and (6.89 ± 2.10) N × mm−2 (for LW+HMDA), both adhesives were found to be unsuitable for interior non-structural use. In addition, the acidity of LW resulted in relatively high wood failure (70%) in the adhesive joints tested. Improved crosslinking of LW with HMDA was reflected in improved resistance of LW+HMDA adhesive joints to water degradation. In conclusion, HMDA is a promising additive for improving the adhesive performance of LW adhesives.

Effect of σ-Phase on the Strength, Stress Relaxation Behavior, and Corrosion Resistance of an Ultrafine-Grained Austenitic Steel AISI 321

This paper reported the results of research into the effect of Equal Channel Angular Pressing (ECAP) temperature and 1-h annealing temperature on mechanical properties, stress-relaxation resistance, and corrosion resistance of austenitic steel AISI 321L with strongly elongated thin δ-ferrite particles in its microstructure. The formation of α′-martensite and fragmentation of austenite grains takes place during ECAP. Ultrafine-grained (UFG) steels demonstrate increased strength. However, we observed a reduced Hall–Petch coefficient as compared with coarse-grained (CG) steels due to the fragmentation of δ-ferrite particles. UFG steel specimens were found to have 2–3 times higher stress-relaxation resistance as compared with CG steels. For the first time, the high stress-relaxation resistance of UFG steels was shown to stem from a internal stress-relaxation mechanism, i.e., the interaction of lattice dislocations with non-equilibrium grain boundaries. Short-time 1-h annealing of UFG steel specimens at 600–800 °C was found to result in the nucleation of σ-phase nanoparticles. These nanoparticles affect the grain boundary migration, raise strength, and stress-relaxation resistance of steel but reduce the corrosion resistance of UFG steel. Lower corrosion resistance of UFG steel was shown to be related to the formation of α′-martensite during ECAP and the nucleation of σ-phase particles during annealing.