Real time diagnostics of gas/water assisted injection moulding using integrated ultrasonic sensors

Advances in Polymer Technology

Zhang

Dong

et al. 2020

Injection molding is one of the most significant material processing methods for mass production of plastic products. It is widely used in various industry sectors, and its products are ubiquitous in our daily life. The settings and optimization of the injection molding process dictate the geometric precision and mechanical properties of the final products. Therefore, sensing, optimization, and control of the injection molding process have a crucial influence on product quality and have become an active research field with abundant literature. This paper defines the concept of intelligent injection molding as the integral application of these three procedures—sensing, optimization, and control. This paper reviews recent studies on methods for the detection of relevant physical variables, optimization of process parameters, and control strategies of machine variables in the molding process. Finally, conclusions are drawn to discuss future research directions and technologies, as well as algorithms worthy of being explored and developed.

Section: Ultrasound Ultrasound Waves Are Mechanical Wavesmentioning

confidence: 99%

Intelligent Injection Molding on Sensing, Optimization, and Control

Advances in Polymer Technology

Zhang

Dong

et al. 2020

“…In WACIM, the thickness of the layer walls significantly affects the mechanical properties of molded products and is an important factor in judging the quality of the products . Many studies have been conducted to investigate the thickness and distribution of residual walls of the products . Kuang et al .…”

Section: Introductionmentioning

confidence: 99%

“…employed ultrasound to monitor the injection‐molding process and characterize the polymer morphology changes. Mulvaney‐Johnson et al . applied an ultrasound sensor system for real‐time diagnosis of water‐ and gas‐assisted injection molding.…”

Section: Introductionmentioning

confidence: 99%

Nondestructive measurement of layer thickness in water‐assisted coinjection‐molded product by ultrasonic technology

Xia

J of Applied Polymer Sci

Kuang

et al. 2018

Layer thickness is an important factor in judging the quality of a water‐assisted coinjection molding (WACIM) part. Here, a novel nondestructive method for measuring layer thickness via ultrasonic technology is proposed. The reflected signals from the interface of a WACIM part were measured by an immersed pulse‐echo method and calculated using a transfer function of the medium. Two objective functions were employed to describe the nonsimilarity between the measured signals and the calculated signals. By solving a multiobjective optimization problem, the optimum parameter was obtained and used to calculate the thickness of each layer in a WACIM part. The proposed method was employed to measure the layer thickness of WACIM specimens with different cross sections along the flow direction. Experimental results showed that the proposed method can correctly measure the variation in layer thickness of each layer of a WACIM part. The proposed method has broad application prospects in nondestructively measuring the layer thickness of polymeric parts. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46540.

“…Michaeli et al employed ultrasonic technology for on‐line monitoring of the polymer state during the injection molding process . Ono et al developed a high temperature ultrasonic transducer and utilized it to perform on‐line polymer characterization during microinjection molding, co‐injection molding, and gas assisted injection molding processes . Zhao et al proposed an ultrasonic method for cavity pressure analysis during the injection molding process .…”

Section: Introductionmentioning

confidence: 99%

Crystallization measurements via ultrasonic velocity: Study of poly(lactic acid) parts

J Polym Sci B Polym Phys

Peng

Yang

et al. 2015

Crystallization has significant effects on the physical and mechanical properties of polymer products; therefore, crystallization measurements are important for understanding and predicting polymer products' properties. However, traditional crystallization measurement methods have disadvantages in practical applications because they can be destructive, offline, unsafe, and expensive. Recently, ultrasonic technology has shown great potential as a nondestructive, online, real‐time, and environmentally friendly measurement method for polymer characterization. In this study, a novel measurement method based on ultrasonic technology was proposed to study the crystallization characteristics of poly(lactic acid) (PLA) parts. An annealing process was employed to produce PLA parts with different degrees of crystallinity. A new ultrasonic water immersion method was used to measure the ultrasonic velocities of these annealed PLA parts. It has been found that the plot of the inverse ultrasonic velocity versus the degree of crystallinity shows good linearity over the whole crystallinity range for all three annealing temperatures. The linear relationship between the inverse of the ultrasonic velocity and the crystallinity observed in this study could provide a nondestructive method for investigating the degree of crystallinity of polymers, which can be implemented both offline and online. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 700–708