While injection molding is significantly less wasteful than some other plastic manufacturing methods, waste is still an issue, particularly from purgings, runners, and scrap. But there are some measures that injection molders can take to minimize this or remove it altogether.
Even without increased government regulations regarding the production of plastic waste, part of the responsibility for finding a viable solution falls to the plastic manufacturers. Working with more sustainable materials in injection molding is one answer. But another lies in the processes injection molders use within their own operations. By combining these two factors–materials and processes–manufacturers of plastic components can lead the way to a cleaner, more environmentally viable future for the entire plastics industry.
The Environmental Impact of Injection Molding
Historically speaking, injection molding has always been among the more sustainable manufacturing processes. Known for producing significantly less waste during production, innovations in utilizing recycled and biodegradable materials are only enhancing the eco-friendliness of injection molding.
However, when it comes to sustainability, settling for “good enough” is often not good enough. That’s where optimizing processes for more sustainable plastic manufacturing comes into play.
Optimizing Processes for Sustainable Plastic Manufacturing
When it comes to improving processes for more sustainable plastic manufacturing, there are five core pillars that injection molders can adopt: recycling and waste management, product design, quality control, and technology at the cell.
Waste Management and Recycling
It’s impossible to avoid all waste during the injection molding process; bad parts and sprues are inherent to large-scale production, at least for the foreseeable future. But there are ways to consume or minimize the waste that is created.
At Noble Plastics, we’ve made it a priority to implement closed-loop systems throughout our entire manufacturing process. In this way, we’re able to collect sprue drops as they are made via automated systems, place them in a grinder, and create a material known as regrind. From there, two options exist.
Based on a customer’s product requirements, we may be able to mix the regrind with virgin resin and mold it into a new part. Usually, this is done on a 20/80 regrind to virgin resin ratio, but in certain cases, the ratio can be increased to a whopping 50/50.
When this is not a viable solution (i.e. with high-performance products), the regrind can be sold to recyclers or other companies that can use it at a much higher percentage.
Optimizing Part Designs for Sustainability
Alongside waste minimization and management, part design is essential to improving sustainable plastic manufacturing. Good part design generally uses less plastic in part because it enables manufacturers to plan for processes that consume less.
Lightweight or streamlined designs, material choice, and engineering support through analysis software can all help customers realize the value of an upfront capital investment that will save them money on waste in the long run.
For instance, the biggest producer of waste in injection molding is the sprue from the runner, which is the pathway the molten plastic takes to reach the part geometry. This is usually removed and discarded (or turned into regrind, as mentioned above) but for some components, it is possible to design tooling and parts to remove this entirely through the use of hot runners, hot drops, and hot runner controllers. This ensures that the plastic stays molten until it reaches the geometry so there is no waste along the way.
Quality Control Plans
In terms of sustainability, good quality control processes can enable plastic manufacturers to plan for the needs of their customers upfront. Doing so requires thoroughly understanding the customer’s quality requirements and expectations so the appropriate processes can be put into place.
At Noble, one way we do this is by implementing frontline inspections. This process allows us to catch problems before they turn into bigger problems, which in turn allows us to reduce scrap. Through automation and robots, we’re also able to carry out inline inspections. Which leads us to the final pillar of sustainability in plastic manufacturing: technology at the cell.
Technology at the Cell
One of the most exciting innovations that has helped push sustainability efforts forward in a big way is the integration of technology into injection molding processes.
One specific instance of this at Noble is our use of robots at the cell that can measure, analyze, and even stop a production process in order to reduce waste as much as possible. By setting quality thresholds and implementing means of measuring metrics like temperature, time, and pressure, robots at the cell are able to monitor the production process in real-time.
If any part goes outside of the standards set, our robots automatically discard them. But there is also a limit to this. For instance, if 5 bad parts are made consecutively, the robot can auto-stop the process until we can assess it for problems. The faster we catch something in injection molding, the better we can reduce waste production and save our customers time and money.
Innovations Driving Sustainable Plastic Manufacturing
In order to continue leading the way for the plastic manufacturing industry to take charge of plastic waste production, Noble Plastics has implemented a number of innovations into our own operations. Biodegradable material development and collaborative relationships with researchers are part of it.
Another notable step forward is our development of temperature control monitoring units that can take ingoing and outgoing temperature readings throughout a production process. This system then tracks this data and sends it to our internal cloud in real-time, where our systems can monitor it for inconsistencies. Not only does this give our entire organization access to the same data, which is critical in timely responses, but it also allows us to prevent problems rather than fix them.
Again, when it comes to reducing waste and increasing sustainability, a timely response is absolutely essential.
Noble Aims to be a Leader in Sustainable Plastic Manufacturing
At Noble Plastics, we are committed to continuously improving the sustainability of plastic manufacturing while still delivering the level of quality and service that our customers deserve. We are an injection molding company with decades of experience in the industry and a reputation for staying ahead of the curve. With our climate-controlled facilities and machines that range in tonnage from 35-940 tons, we have the capacity and the capability to deliver everything from small prototyping runs up to full large-scale productions with the same degree of efficiency and performance.
Are you looking for an injection molding partner that focuses on the future while keeping your needs at the forefront? Connect with our team of experts today and find out how we can help you.
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