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Values of parameters such as temperature, humidity, number of plastic products and the location of plastic injection moulds are required to determine the efficiency of plastic injection moulds with a view to improving the quality of the outputs. This article determined the appropriate sensors for the measurement of these essential parameters in the most suitable form of representation of the data to aid a proficient analysis of the data.

The outputs of these sensors were obtained by connecting the sensors to the general-purpose input/output (GPIO) pins of a Raspberry Pi and writing a Python programme for the connected GPIO pins. The values of the outputs of these sensors were represented in a graphical form. The connection of the Raspberry Pi and the sensors were done with a full-sized breadboard and jumper wires. A computer-aided design (CAD) of the connections was produced using Fritzing software.

The appropriate sensors determined are MLX90614 infrared thermometer sensor, DHT11 humidity sensor, pixy2 vision sensor and Neo-6m GPS sensor. This study proposed that the sensors analytic system be applied on an industrial plastic injection mould to measure and display the various parameters of the injection moulds for the purpose of understanding and improving the performance of the injection mould

An electronic system that provides the continuous values of essential parameters of a plastic injection mould in operation.

Polymer rapid tooling (PRT) inserts can be used as injection moulding (IM) cavities for prototyping and low volume production but lack the robustness of metal inserts. Metal inserts can withstand high injection pressure and temperature required, whereas PRT inserts may fail under similar parameters. The current method of parameter setting starts with using the highest pressure setting on the machine and then fine-tuning to optimize the process parameters. This method needs modification, as high injection pressures and temperatures can damage the PRT inserts. There is a need for a methodical process to determine the upper limits of moulding parameters that can be used without damaging the PRT inserts.

A case study analysis was performed to investigate the causes of failure in a PRT insert. From this, a candidate set-up process was developed to avoid start-up failure and possibly prolong tool life. This was then tested on a second mould, which successfully avoided start-up failure and moulded 54 parts before becoming unusable due to safety issues.

Process parameters that are critical for tool life are identified as mould temperature, injection pressure, injection speed, hold pressure and cooling time.

This paper presents a novel method for setting IM process parameters for PRT inserts. This has the potential to prevent failure at start up when using PRT inserts and possibly extend the operating life of the PRT inserts.

The purpose of this study is to compare the overall performance of the injection moulding process by using metallic inserts produced by both conventional technologies and selective laser melting (SLM).

A systematic methodology is proposed for prior evaluation of the effectiveness of conformal cooling channels to reduce cycle time and/or to reduce the scrap rate.

The mould was reengineered considering the SLM process and manufactured. Injection trials were carried out to validate expectations provided by injection simulations, which resulted on good quality parts and a significant decrease on cooling time, and, consequently, on the overall cycle time. The minimisation of scrap provided energy savings and time-to-market reduction.

The initial costs for AM tools still pose some doubts on decision-makers. The challenge of this study is to implement the methodology on a small-scale production and still ensure that benefits are achieved.

The case study selected for this research work is based on a parking sensor housing, which is a plastic part assembled on the vehicle’s front and rear bumpers, therefore, with aesthetics concerns. The part produced with the conventional mould exhibits surface defects that, to be minimised (not eliminated), require a longer packing time to diminish the sink marks.

The economic impact of the use of SLM is relevant despite the low batch size for the case study presented. Energy savings are achieved due to scrap reduction and shorter cycle time.

The systematic methodology proposed for prior evaluation of the advantages of conformal cooling is possible to be applied both on small scale and high production series.

The purpose of this paper is to provide a demonstration of the application of techniques for robust optimization for improvement of the injection moulding processes in an injection moulding small and medium sized enterprise (SME).

A critical to quality characteristic (CtQ) which is connected to assembly problems is the subject of investigation. The CtQ is not directly measurable. The variation in a dimension of a product, which is correlated to the CtQ, is studied using design of experiments (DoE) and Taguchi methods. A two-cavity mould is used in the injection moulding process. To evaluate the robustness of the process using signal-to-noise analysis, the data were transformed to compensate for the systematic differences between the mould cavities.

The initial results showed that finding optimal process parameter settings commonly valid for both cavities was impossible. After a modification of the mould, the experiments were rerun and optimal settings could be found.

Applying DoE techniques in small and medium-sized injection moulding companies is far from common practice. This case study demonstrates a method to apply DoE with five process parameters which can serve as a standard method to prepare production when a new mould is used for the first time.

The originality is connected to the combination of the applied methods and, in the context of the case study, carried out in an SME unfamiliar with the power of the applied methods. The value of the paper is to demonstrate the power of the most powerful technique in quality engineering to improve an injection moulding process within the context of SMEs. The authors would accentuate the point that the true power becomes visible when this powerful technique is introduced into an organization with very little understanding of the technique. In addition, the case study is valuable to practitioners because it proposes a new scientific and systematic approach to understand and optimize the start-up of the moulding process.

The purpose of this paper is to present a technique of fabricating profiled conformal cooling channels (PCCC) in an aluminium filled epoxy mould using rapid prototyping (RP) and rapid tooling (RT) techniques and to compare the cooling times for the moulds with circular and profiled channels experimentally. The cooling channels in injection mould tools have a circular cross section. In a PCCC, the cross sectional shape is so designed that the flat face surface of the channel facing the cavity follows the profile of the cavity. These types of channels can be manufactured through RP and RT techniques.

A part to be moulded was designed and modelled. Two moulds were then designed with the part cavity, one having a circular channel and the second with a profiled channel, both having the same cross sectional area for coolant flow. The channel patterns were designed with supports according to their position regarding height and distance from the cavity as designed earlier. Both channels have the same distance from the cavity wall. RP patterns were produced for both channels and part using the Thermojet 3D printer. The cooling channel and the moulded part patterns were then assembled as designed in the moulds. Moulding frames were fabricated with aluminium plates and the pattern was placed in the frames. Epoxy was poured on the pattern and then cured. The moulded part and the channel patterns embedded inside epoxy were melted out during the final curing cycle, leaving behind the circular‐ and profiled‐cooling channels in the moulds. For the cooling time measurement, injection moulding was done with moulds with circular and profiled channels. Moulded part temperature will be recorded by embedding thermocouples within the mould cavities.

A technique for the manufacture of cooling channels of different profiles in epoxy moulds was presented. Experimental analysis for temperature measurement for the moulded part with injection moulding process showed that PCCC mould has less cooling time then mould with circular channels.

The technique presented is based on the metal‐filled epoxy materials used in RT and was obtained using a specific test part. Epoxy tooling can be a useful alternative of metallic mould to produce injection mould tools. A limitation for the epoxy moulds is that they have a limited life as compared with metallic moulds.

This is a new technique of manufacturing moulds with cooling channels using RP/RT techniques. Moulds with different channel cross sections can be manufactured using this technique.

This paper aims to present a comparison between selective laser sintering and injection moulding technology for the production of small batches of plastic products.

The comparison is based on analysing the time–cost efficiencies of each manufacturing process regarding the size of the series for the selected product sample. Both technologies are described and the times and costs of those individual processes needed to create a final product are assessed when using each of the manufacturing processes.

The study shows that the time-cost efficiency of the selected laser sintering technology increases according to the complexity of the product and decreases with increasing series size and product volume.

The study and absolute values of the presented results are limited to a selected plastic product, but the series size-focused efficiency analysis could be expanded to general cases.

The presented analysis could be used as a general guideline for a decision-making process regarding the more efficient manufacturing method. In addition, the results show the viability of using selective laser sintering during the early stages of production when fast product availability is required, regardless of the series size. Also, some complementary effects of using both technologies in the serial production of the same part are discussed.

The purpose of this study is to demonstrate and characterise a soft-tooled micro-injection moulding process through in-line measurements and surface metrology using a data-intensive approach.

A soft tool for a demonstrator product that mimics the main features of miniature components in medical devices and microsystem components has been designed and fabricated using material jetting technique. The soft tool was then integrated into a mould assembly on the micro-injection moulding machine, and mouldings were made. Sensor and data acquisition devices including thermal imaging and injection pressure sensing have been set up to collect data for each of the prototypes. Off-line dimensional characterisation of the parts and the soft tool have also been carried out to quantify the prototype quality and dimensional changes on the soft tool after the manufacturing cycles.

The data collection and analysis methods presented here enable the evaluation of the quality of the moulded parts in real-time from in-line measurements. Importantly, it is demonstrated that soft-tool surface temperature difference values can be used as reliable indicators for moulding quality. Reduction in the total volume of the soft-tool moulding cavity was detected and quantified up to 100 cycles. Data collected from in-line monitoring was also used for filling assessment of the soft-tool moulding cavity, providing about 90% accuracy in filling prediction with relatively modest sensors and monitoring technologies.

This work presents a data-intensive approach for the characterisation of soft-tooled micro-injection moulding processes for the first time. The overall results of this study show that the product-focussed data-rich approach presented here proved to be an essential and useful way of exploiting additive manufacturing technologies for soft-tooled rapid prototyping and new product introduction.

This papers aims to study the influence of water absorption on the mechanical properties of poly lactic acid (PLA) and PLA/Wood composites. Virgin PLA and PLA/Wood double-bone-shaped specimens were prepared by two methods: injection moulding and 3D printing. The results were compared to each other and showed the influence of the production method on the properties of the produced parts.

Morphology studies were done by scanning electron microscopy (SEM) from fracture surfaces of tensile and notched impact specimens of all samples. Tensile properties were analysed by the production and testing of dog-bone-shaped samples. Heat deflection temperature (HDT) was tested, as also was the crystallinity of the tested samples by differential scanning calorimetry.

The values for notched impact strength were higher upon water uptake in the case of injection-moulded specimens, which was not the case with 3D-printed specimens. Tensile properties of the specimens produced by both methods were reduced after water absorption tests. Values of the HDT were also lower after water absorption tests studied for both processing methods.

Morphology studies were done by SEM from fracture surfaces of tensile as well as notched impact specimens of injection-moulded and 3D-printed samples. The effect of water storage on various samples was tested. The two different production technologies were compared to each other owing to their influence of water storage. This study also dealt with NFC compounds and produced NFC composites and the influence of water storage on these samples.

In this work, the changes to stereolithography (SL) resin mechanical properties during the injection moulding process were evaluated. A multi‐impression SL mould was built and used to inject a series of small flat mouldings. The fixed half SL tool insert included recesses to accommodate tensile test specimens. Tensile test specimens made from SL resin were positioned in these recesses and plastic parts were injected. After injecting a predetermined number of mouldings, tensile tests were performed using the tensile test specimens. The results from the tensile tests show that the thermal cycling encountered during the injection moulding process did not significantly affect the mechanical properties of the resin. Observations indicate that decrease in the temperatures encountered in the tool may lead to longer tool life.

This paper aims to emphasize compared experimental analysis of influence of hybrid and classic moulds on the properties of moulded parts and the processing parameters. Such analysis enables optimization of processing parameters in case of the hybrid mould.

Representative moulded part and appropriate hybrid and classic moulds have been designed and manufactured. The experimental work contains a screening design and the main central composite design for analysing the performance of both moulds and moulded parts properties. In case of hybrid mould a numerical optimization of processing parameters was used.

It was found that hybrid moulds can be successfully applied for production of thin‐wall moulded parts with some limitations. The compressibility of prototype mould inserts was higher compared to classic inserts. The differences in thermal properties of mould inserts materials result in different moulded part properties and mould cavity wall temperature fields. These differences can be reduced by optimizing the processing parameters.

RT technologies can be usefully applied for fast production of moulds for injection moulding. The potential user of hybrid moulds should be aware of the influence of prototype inserts on the moulded part properties. Guidelines for optimization can be used for fast achieving of parameters from optimal processing window.

This paper shows a detailed analysis of influence of hybrid and classic moulds on the thermoplastic moulded part properties. Some of these influences are explained in detail, which was not found in the related papers. In this paper, a further step was made by optimizing the processing parameters in case of hybrid mould.