Hot-pressing design of tubular polyester nonwoven lining material for pipeline rehabilitation

2021 ◽  
pp. 152808372110277
Author(s):  
Lisong Fu ◽  
Shujie Zhang ◽  
Rui Wang ◽  
Guoquan Cao ◽  
Mengke Jing ◽  
...  

In view of the strength loss and dimension shrinkage of polyester nonwoven used for the sewage pipeline in the hot-pressing process, the response surface methodology was proposed to optimize the technological parameters of lining material. Select the temperature, time and pressure to enhance the hot-pressing process of lining material with the response value of the rate of dimensional change and tensile strength. The results showed that the temperature was 180°C, time was 3s, and pressure was 2.8MPa. Under this process, the rate of dimensional change was 4.23%, transverse tensile strength was 7.95MPa, and longitudinal tensile strength was 5.26MPa. It showed that the response surface methodology had practical application value, and provided a theoretical basis for the hot-pressing parameters of lining material with maximum tensile strength and minimum dimensional shrinkage. The paper also tested the adhesive strength, air permeability and water permeability of lining material under the optimal process, founding that the prepared material had excellent adhesive strength, air permeability, water permeability, and could meet the construction requirements of pipeline rehabilitation and the use requirements of conveying medium.

2013 ◽  
Vol 756-759 ◽  
pp. 54-59
Author(s):  
Ai Min Tang ◽  
Shan Zhao ◽  
Chao Feng Jia

Response Surface Methodology (RSM) was used to study the relationship between the strength properties of poly ( p-phenylene terephthalamide)-PPTA paper and the preparation parameters, such as hot pressing temperature, hot pressing pressure, proportion of PPTA short-cut fiber and beating degree of PPTA-pulp. The results showed that: hot pressing temperature, hot pressing pressure have highly significant influences on the tensile strength and wet strength. The proportion of PPTA short-cut fiber has significant effects on the tensile strength and wet strength. The beating degree of PPTA-pulp also affected the tensile strength significantly. At the same time, the tensile strength was significantly influenced by the interaction between hot pressing temperature and the proportion of PPTA short-cut fiber as well as the interaction between hot pressing temperature and the beating degree of PPTA-pulp. The interaction between hot pressing temperature and hot pressing pressure has significant influences on wet strength, whereas the other factor interactions were not significant. The quadratic formula was established by optimizing the results of multiple regressions. And the model was highly consistent with the experiment. This model could be used to analyze and predict the main strength properties of PPTA paper and also might be used to optimize the production process of PPTA paper and control its quality.


Author(s):  
Ravi Butola ◽  
Ranganath M. Singari ◽  
Qasim Murtaza ◽  
Lakshay Tyagi

In the present work, nanoboron carbide is integrated in the aluminum matrix using friction stir processing: by varying process parameters, that is, tool pin profile, tool rotational speed and tool traverse speed, based on Taguchi L16 design of experiment. A self-assembled monolayer is successfully developed on the substrate to homogeneously and uniformly distribute the reinforcement particles. Response surface methodology and artificial neural network models are developed using ultimate tensile strength and total elongation as responses. Percentage absolute error between the experimental and predicted values of ultimate tensile strength and total elongation for the response surface methodology model is 3.537 and 2.865, respectively, and for artificial neural network is 2.788 and 2.578, respectively. For both the developed models experimental and forecasted values are in close approximation. The artificial neural network model showed slightly better predictive capacity compared to the response surface methodology model. From the scanning electron microscopy micrograph, it is evident that throughout the matrix B4C reinforcement particles are well distributed also; with increasing tool rotational speed grain size decreases up to 1200 r/min; on further increasing the tool rotational speed particles starts clustering.


2021 ◽  
Vol 406 ◽  
pp. 319-333
Author(s):  
Tahar Saadi ◽  
Mohamed Farid Benlamnouar ◽  
Nabil Bensaid ◽  
Amar Boutaghane ◽  
Mohamed Amine Soualili ◽  
...  

The present study, aims to investigate, under welding parameters of current, voltage and gas flow, the effects of welding parameters on tensile strength of AISI 304L ASS welds using response surface methodology (RSM). The RSM and variance analysis (ANOVA) were used to check the validity of quadratic regression model and to determine the significant parameter affecting tensile strength of welds. Hence, ANOVA clearly revealed that the contribution of each factor is 71.40% of voltage, 19.2% of current and 8.30% of gas flow. It was found that combined contributions of welding parameters contributes significantly to the metallurgical changes by varying fractions, morphology and grain size of metallic compounds. Furthermore, the optimum automatic welding conditions lead to produce the best possible weld quality in the range of our experiment using desirability function approach for single response of RSM optimization factors, in which it concluded that tensile strength components are influenced principally by voltage. Finally, the ranges for best welding conditions are proposed for serial industrial production.


In the present study, Response Surface Methodology (RSM) is implemented to determine optimum process variables of TIG welding of Incoly-800HT sheets. Voltage, Welding current and speed of welding are considered as factors. Ultimate tensile strength at room temperature, yield strength at room temperature, ultimate tensile strength at 7500C, yield strength at 7500C and toughness are considered as responses. The Design of Experiment based on central composite response surface design, experimenting is formulated using the Design Expert 12 software. Grey Relational Analysis (GRA) carried on the responses and grey relational coefficients are calculated. The grey relational coefficients are subjected to Principal Component Analysis (PCA) using PAST 3.26 software that transforms the five responses into a single response. The optimization of parameters is carried by Response Surface Methodology and contribution by each input parameter is estimated by ANOVA (Analysis of Variance).


2019 ◽  
Vol 9 ◽  
pp. 184798041985584 ◽  
Author(s):  
Mohammadhossein Saberian ◽  
Faramarz Ashenai Ghasemi ◽  
Ismail Ghasemi ◽  
Sajjad Daneshpayeh

In this study, the response surface methodology was used to investigate the tensile properties of epoxy/graphene nano-platelets/carboxylated nitrile butadiene rubber ternary nanocomposites. Box–Benhken method was used to design experiments for four factors consisting of graphene nano-platelets (at 0, 0.75, and 1.5 wt%), carboxylated nitrile butadiene rubber (0, 5, and 10 wt%), hardener contents (80, 90, and 100 phr), and also different post curing temperature (130, 140, and 150°C). After the samples were prepared, a tensile test was performed to obtain the tensile strength, tensile modulus, and elongation at break of nanocomposites. Moreover, field-emission scanning electron microscopy was used to observe the state of graphene nano-platelets dispersion. The results obtained from the tensile tests showed that increasing the graphene nano-platelets, carboxylated nitrile butadiene rubber, and hardener contents and high post curing temperature reduced the tensile strength. The optimum value of tensile modulus was achieved at low concentration of carboxylated nitrile butadiene rubber and high contents of graphene nano-platelets, whereas maximum elongation at break occurred at high content of carboxylated nitrile butadiene rubber and low concentration of graphene nano-platelets and hardener. In addition, a second-order polynomial model was used to correlate the tensile properties of ternary nanocomposites to the desired factors. Finally, contour plots were used to determine optimum values of the desired factors. It was seen that the presence of 10 wt% of carboxylated nitrile butadiene rubber in the epoxy matrix increased the elongation at break by the considerable amount of ∼49%.


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