Proposta de redução de desperdício de matéria-prima em uma indústria de batata pré-frita congelada / Proposal for reducing raw material waste in a frozen pre-fried potato industry

A busca por melhorias no sistema produtivo de uma indústria de batata pré-frita congelada, localizada no alto paranaíba (minas gerais), motivou uma pesquisa-ação com objetivo de reduzir a quantidade de matéria-prima desperdiçada no setor de recebimento de matéria-prima. Foi utilizado o método dmaic, que significa “definir”, “medir”, “analisar”, “melhorar” e “controlar”, apoiado pelo desenvolvimento de hipóteses, testes e verificações em campo e utilização das ferramentas da qualidade. O estudo propôs a definição dos defeitos aceitáveis de matéria-prima e fez testes evidenciando que os defeitos externos (estéticos), presentes apenas na casca, poderiam ser reduzidos por uma nova passagem pelo processo na qual as batatas são descascadas. Por fim, concluiu que a incorporação de uma esteira adicional no processo contribuiria para economizar uma quantidade significativa de matéria-prima, estimada em mais de 120 mil reais anuais apenas em uma linha de produção. 

Utilização de técnicas do planejamento de experimentos na otimização de um processo de torneamento da superliga NIMONIC 80A

As ligas a base de níquel possuem uma composição química com elevado teor de elementos de liga, os quais são responsáveis por suas propriedades mecânicas e térmicas. Sua vasta utilização se da ao seu bom desempenho em altas temperaturas. O objetivo deste trabalho foi estudar o processo de usinagem via torneamento cilíndrico externo da liga a base de níquel Nimonic 80A, utilizando ferramentas do projeto de experimentos como a Metodologia de Taguchi e a Metodologia de Superfície de Respostas para o auxílio à resolução de problemas com múltiplas respostas em experimentos de usinagem, visando analisar qual o melhor arranjo dentre os fatores estudados, tendo como variável resposta a rugosidade superficial (Ra) e comprimento de corte (Lc). Os ensaios de usinagem foram realizados em um torno CNC, sendo considerados os seguintes parâmetros de usinagem: velocidade de corte (75 e 90 m/min), profundidade de usinagem (0,8 e 1,6 mm) e avanços (0,12 e 0,18 mm/v), pastilhas CP250 e TP2500, corpo de prova feito com material Nimonic 80A laminado a quente e Solubilizado, por fim, o fluido refrigerante variando em Mínima quantidade de Fluido (MQF) e abundante. Todo o processo foi conduzido em ciclos, em que cada ciclo terminava quando atingisse o comprimento de avanço máximo (Lf). Após cada etapa do torneamento foram realizadas as medidas do desgaste ferramental, bem como a rugosidade das peças. Pôde–se observar que o avanço apresentou maior significância com relação à rugosidade e comprimento de corte, levando a concluir que para menores valores de avanço, menores valores de rugosidades e maiores valores de comprimento de corte serão encontradosThe nickel-based alloys have a chemical composition with high content of alloying elements, which are responsible for their mechanical and thermal properties. Its widespread use in these areas is mainly due to its performance at high temperatures. The propose of this work is to study the machining process in a cylindrical external turning in a nickel based alloy Nimonic 80A, using tools of the design of Experiments such as Taguchi Method and Response Surface Methodology for assistance to solve problems with multiple responses machining experiments aimed at analyzing what are the best setting among the factors studied with variable response to surface roughness and cutting length. The machining tests were performed on a CNC lathe, being considered the following machining parameters: cutting speed (75 and 90 m / min), depth of cut (0.8 and 1.6 mm) and feed rate (0.12 and 0.18 mm / V), TP2500 and CP250 tools, workpiece of Nimonic 80A material hot rolled and annealed and Fluid Lubricant varying amount in Minimal Quantity of Fluid (MQF) and abundant. The whole process was conducted in cycles where each cycle ended when it reached the maximum feed length (Lf). After each step of turning, were performed the measurements of the tool wear and the roughness of the parts. It can be observed that the factor feed had greater significance with respect to roughness and cutting length, leading to the conclusion that the lower were feed rate, lower values of roughness and higher values for cutting length will be foundCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Utilização de metaheurísticas combinada a diferentes métodos de aglutinação para a otimização de um processo de torneamento com múltiplas respostas

The nickel-based alloys have a chemical composition with high content of alloying elements, which are responsible for their mechanical and thermal properties, but these features interfere in the machining. Its widespread use in these areas is mainly due to its performance at high temperatures, which is given by some of its characteristics, such as high mechanical strength at elevated temperature, creep, fatigue and corrosion resistance. The objective of this work was to study and evaluate the machining process by external cylindrical turning of the nickel alloy based Nimonic 80A and propose new ways of thinking in multiple response optimization process using different search methods and different methods of agglutination from modeling process. To this, the variables analyzed were: surface roughness (Ra) and cut length (Lc). The machining tests were performed on a CNC lathe, being considered the following machining parameters: cutting speed (75 and 90 m / min), depth of cut (0.8 and 1.6 mm) and feed rate (0.12 and 0.18 mm/revolution), TP2500 and CP250 tools, test body made of Nimonic 80A material hot rolled and annealed and Fluid Lubricant varying amount in Minimal Quantity of Fluid (MQF) and abundant. The whole process was conducted in cycles where each cycle ended when it reached the maximum feed length (Lf). The entire process was conducted in cycles, wherein each cycle ended when it reached the maximum feed length (Lf). After performed the process modeling, were used GRG algorithm, three different meta-heuristics and 4 different agglutination methods and evaluated. To evaluate the performance of meta-heuristics and agglutination methods we used the method of Taguchi L16, reaching the conclusion that all showed significance in the proposed evaluation, and the methods tested here showed efficiency for such researchAs ligas a base de níquel possuem uma composição química com elevado teor de elementos de liga, os quais são responsáveis por suas propriedades mecânicas e térmicas; porém, estas características dificultam demasiadamente o processo de usinagem. Sua vasta utilização nestas áreas deve-se principalmente ao seu desempenho em altas temperaturas, que é dado por algumas de suas características intrínsecas, como: alta resistência mecânica em temperatura elevada, à fluência, à fadiga e boa resistência à corrosão. O objetivo deste trabalho foi avaliar o processo de usinagem por torneamento cilíndrico externo da liga a base de níquel Nimonic 80A, bem como propor novas formas de pensar processos de otimização com múltiplas respostas utilizando diferentes métodos de busca e diferentes métodos de aglutinação a partir de modelagem de processo. Para tal, foram analisadas as variáveis respostas rugosidade superficial (Ra) e comprimento de corte (Lc). Os ensaios de usinagem foram realizados em um torno CNC, sendo considerados os seguintes parâmetros de usinagem: velocidade de corte (75 e 90 m/min), profundidade de usinagem (0,8 e 1,6 mm) e avanços (0,12 e 0,18 mm/v), pastilhas CP250 e TP2500, corpo de prova feito com material Nimonic 80A laminado a quente e Solubilizado, por fim, o fluido refrigerante variando em Mínima quantidade de Fluido (MQF) e abundante. Todo o processo foi conduzido em ciclos, em que cada ciclo terminava quando atingisse o comprimento de avanço máximo (Lf). Depois de realizada a modelagem, foram utilizados 3 diferentes meta-heurísticas e 4 diferentes métodos de aglutinação além do algoritmo GRG. Para se avaliar o desempenho das meta-heurísticas e métodos de aglutinação foi utilizado o método de Taguchi L16, chegando a conclusão de que todos mostraram significância dentro da avaliação proposta, sendo que os métodos aqui testados mostraram eficiência para tal pesquis

Optimization of Cutting Process Parameters in Nickel-Based Alloy Nimonic 80A using Multi-Objective Function and Taguchi Analysis

Nickel alloys are characterized by presenting a high cost in manufacturing of machined parts because of these material's characteristics makes it difficult to machine. Based on the complexity and in the widespread applications, the nickel-alloy machining needs to be judiciously investigated. The objective of this work is the study of the machining by external cylindrical turning on a CNC Machining, using a nickel-based alloy Nimonic 80A to optimize the variable response Roughness (Ra) and Length of Cutting (Lc). The proposed analysis to find the best values of Ra and Lc using multi objective functions optimized with Meta-Heuristic techniques (Simulated Annealing and Genetic Algorithm) and using two different methods of agglutination (Desirability and Average Percentage Distance). The design of the experiment was a Taguchi Orthogonal Array L8, operating in two levels. The machining experiments were accomplished considering the machining parameters: cutting speed (75 and 90 m.min-1), cutting depth (0,8 and 1,6 mm), feed rate (0,12 and 0,18 mm.rev-1), kind of tool (TNMG160404R-UX TP2500 and TNMG160404R-UX CP250) and environment (minimum quantity of fluid (MQF) and flood).Published in International Journal of Advances in Engineering & Technology (IJAET), Volume 16 Issue 4, pp. 262-273, August 2023. Available at: https://www.ijaet.org/media/11I76-IJAET1604814-v16-i4-262-273.pd

Forage Mass and Leaf Area Index in Multispecies Pastures Under Continuous Stocking

The association of different species in a pasture ecosystem is a challenge for grazing management, where the leaf area index (LAI) is the end result of interactions between plant-animal-environment. Therefore, this study evaluated the effects of grazing management strategies (GMS) considering forage canopy heights on forage mass production (FM) and LAI in multispecies pastures. The experiment was conducted at the Instituto of Zootecnia in Nova Odess, SP in autumn (June 2021) and spring (December 2021). Multispecies pastures were composed of aruana grass (Megathyrsus maximum cv. Aruana) and a mix of forage legumes: calopo (Calopogonium mucunoides), macrotyloma (Macrotyloma axillare) and stylo (Stylosanthes macrocephala+ Stylosanthes capitata). The study was conducted in four randomized blocks with four treatments (grazing management strategies – GMS: 15, 30, 45 and 60 cm canopy heights) and four replications (500 m²/each paddock), with continuous stocking of sheep. For the FM evaluation, the forage was cut at soil level in three 0.25 m² areas, representative of the average paddock height. The samples were weighed, homogenized and divided into two subsamples for component separation and total dry matter quantification after drying in a forced-air oven at 65 °C for 72 hours. The leaf area (cm²) was determined using a LI-COR model 3100 measuring device to calculate the total covered soil area (m²) and to find the LAI values for aruana grass (LAIaruana), legumes (LAILeg) and aruana grass + legumes (LAITotal). Analysis of variance was performed by SAS software using proc MIXED. The Tukey test was applied for comparison of means (P<0.05). There was a significant effect for GMS and season in FM (P<0.0001; P=0.00061). The highest FM value found was for 60 cm GMS, with 8883±489.5 kg DM.ha-1, compared to 15 cm with 5714±489.5 kg DM.ha-1, and the largest FM was observed in autumn (7977±346,2) compared to spring (6505±346,2 kg DM.ha-1,). There was interaction between GMS and season for aruana grass leaf blade area (LBAG) and legume leaflet (LL), (P=0,0038; P=0.0060). LBAG and LL presented smaller values for 30 cm GMS during autumn, of 641 and 3± 86,27 kg DM.ha-1. There was seasonal effect (P<0.0001) for the dead material component (DMC), with values of 4412 and 1989± 227.1 kg DM.ha-1, respectively, in autumn and spring. There was a GMS and season effect for LAIaruana and LAITotal (P= 0.0030; P<0.0001, respectively). The highest values of LAIaruana and LAITotal were observed for GMS of 60 cm with values of 4.1 and 4.7, while, the lowest values observed were 2.2 and 2.3 for 15 cm GMS, respectively. The highest values observed for the season were 4.3 and 4.7 during spring for LAIaruana and LAITotal. There was a significant interaction between GMS and season for LAILeg (P= 0.0145), and the highest value was observed for the 60 cm GMS in spring (1.1). Decreasing favorable edafoclimatic conditions and increased grazing pressure by reducing grazing management heights reflected LBGA and LL mass production decrease, contributing to the LAI reduction, but the legumes’ presence increased LAI values. DMC mass presence in unfavorable conditions contributed to the lower LAI values, directly affecting the plants’ photosynthetic apparatus, with lower quantity and quality, impacting forage plant resources. Therefore, FM and LAI were affected by GMS and season. It is not advisable to use grazing management strategies below 45 cm for LAI maintenance, mainly for forage legumes during unfavorable periods

Canopy height impact on legume mass and Megathyrsus maximus tiller dynamics in mixed pastures

The use of grazing management strategies can influence canopy structure and the permanence of legumes. The objective of this work was to evaluate the determination of forage canopy heights as a grazing management strategy regarding herbage mass composition and tiller population dynamics in multispecies pastures comprising Megathyrsus maximus cv. Aruana and the legumes Macrotyloma axillare, Calopogonium mucunoides and Stylosanthes spp. Four treatments, defined by canopy heights of 15, 30, 45 and 60 cm, were evaluated in a randomised block design with four replications. The evaluations were performed under continuous stocking with sheep. Taller pastures (45 and 60 cm) contained greater (P < 0.05) total herbage mass of Aruana leaves and stems and also higher mass of legumes than smaller pastures (15 and 30 cm). The grass tiller population density was different between heights (P < 0.05) of 2.71, 2.02, 1.97 and 1.47 tillers/m2 for heights of 15, 30, 45 and 60 cm, respectively. The tiller appearance rate was highest in tall pastures (P < 0.05) and the lowest rate and stability index were found in 15 cm pastures. Aruana guineagrass and forage legumes can be managed in the height range of 30–60 cm under continuous stocking