What Is A Hot Runner?
When hot runner technology was first introduced to the plastics industry more than five decades ago, it revolutionized injection molding processing capabilities by improving molded part quality, enhancing operational efficiencies, reducing scrap, and saving money. A hot runner system is a molten plastic conveying unit used within an injection mold. Another way of saying that a hot runner system consists of heated components (usually by electricity) used inside the plastic injection molds, which brings the molten plastic from the barrel of an injection molding machine into the cavities of the mold. Hot runner melt channels can have different sizes; the size needed depends on factors such as resin type, injection speed, fill rate, and the molded part. A temperature controller(standalone controller or controls from the injection molding machine)
Hot Runner Productivity Series
Hot Runner Productivity Series Register for special pricing, tools, and training to help with hot runner processing, energy savings, and maintenance. High-Cavity Hot Runner Productivity Series Highlights This 5-post series follows a normal order of events on the molding floor from before you start molding to more advanced molding cell automation. kW Demand - We'll show you how and why you should reduce kW demand. Maintenance - This covers preventative maintenance of hot runner systems, cables, and controllers. Troubleshooting - How should you react when alarms or other things go out of normal range? Processing - What's happening behind the scenes in your hot runner system, and why does it matter for processing (better cavity-to-cavity
Hot Runner Injection Molding Process
Injection Molding Process and Hot Runner Systems Processing injection molds used to be considered a black art. Then came along scientific molding that decoupled fill (cavity is filled 98% with injection speed), pack (finish filling and apply pressures), and hold (allow the part to cool). Processing engineers control four plastic variables: Temperature/Heat, Flow, Pressure, and Time/Cooling. There are two details we want to point out that help shape our viewpoint on processing. Melt Flow Index First, most people think the term "Melt Flow Index" represents viscosity (resistance to flow). It is measured in grams per 10 min within a comparison test to other resins. It is a molecular weight, not viscosity, just a reference point. Plastic also does not follow Newton's law of viscosity. It's a
Hot Runner Troubleshooting
Hot Runner Troubleshooting First, Staying Out of Trouble MoldMaking Technology® and Plastics Technology magazines published articles about hot runner troubleshooting that included the importance of proper hot runner system startup. While this blog is about troubleshooting, it is fair to say that the best way to get out of trouble is to stay out of trouble. Proper start-up prevents the tool from leaking plastic. Further, it does this while minimizing hot runner system wear and downtime. And, as previously shown in our post about kW demand, it saves on peak demand kW costs. It also helps to balance shop loading of amperage. The Ins and Out of Hot Runner Temperature Control, MoldMaking Technology, 11/8/2021 by yours truly, Chad Root and Manny Diaz, Fast Heat by Spark
Hot Runner Maintenance Guide
Preparing for Production - Hot Runner Maintenance Guide This guide includes the blog post below and an adjoining slide deck. The blog post below is a reference guide with links to detailed explanations and visual examples we have compiled over the years (photos and videos). Use the adjoining slide deck for a speedy review of hot runner maintenance best practices. See the bottom of this page for the table of contents. Download the adjoining slide deck here: >231110-SPAR-Production Ready Maintenance Guide Training Firstly, this section focuses on maintenance training and includes our tips, outside resources for reference, 3rd party training opportunities, and a software recommendation to help manage tooling maintenance responsibilities. Click here for the entire training post: >Training w/
Hot Runner kW Demand
Hot Runner kW Demand Impacts Electrical Cost & Shop Loading An electricity bill has two main usage categories: kilowatt-hours (kWh) and kW demand. kWh is a calculation of wattage multiplied by the number of hours used, divided by 1000. We pay approximately $.10/kWh used in a given month. kW demand is the highest kW recorded during peak hours. This bills around $9.00 per kW. How high of a kW demand does the electric company have allocated to you? The higher you peak, the more it costs. Hot Runner Electrical Consumption Further, a given injection mold and hot runner system will require a certain amount of wattage to achieve and maintain the setpoint. That is just a factor of the tool's heat/loss design. Once the tool is
Common Hot Runner Cable Connection Problems
Common Hot Runner Cable Connection Problems Hot Runner Connector Anatomy Simple fixes can result in significant differences in your manufacturing process. You do not have to give in and just accept some common aggravating problems on the manufacturing floor. You may not think it’s worth changing some of the issues mentioned here. But what if these would make a difference to your bottom line? The problems that occur with hot runner cables can have a ripple effect on your whole manufacturing process and, of course, your finances. If the problem areas can be identified, often there are simple options to help. After all, streamlining manufacturing processes and lowering maintenance costs are definitely things we should strive for on a daily basis, right? Hot Runner Cable Problems: Pushed-Back/Bent
Heated Tapered Nozzle
Heat Transfer and Uniformity by Zeiger and Spark Industries Okay, one more time for those of you who may have missed it…for those way in the back…anyone who knows anything about injection molding knows the importance of having optimum control over heat profiles…it is top priority! Temperature affects every step of the injection-molding process and must be appropriately managed. Further, inadequate or excessive temperatures can leave flaws in the finished product and damage the injection machine. During the injection process, temperatures that are too low can lead to flow marks or wavy lines on the surface of the finished part. Identifying and controlling the temperatures at each point throughout plastic injection molding will ensure that the process runs smoothly. Knowing the flaws that can occur in the
Hot Runner Performance
Preparing for Production Hot Runner performance is critical to maintaining production schedules and eliminating costly downtime. Following a pre-production checklist to ensure all tools are in place and ready to go gives your team the ability to work efficiently and effectively, saving both time and money. Having the tools to ensure your hot runner performance is peak is where Spark Industries comes in. Necessity is the mother of invention Manny Diaz developed the MoldXChecker® as a result of feedback from customers who stated they would like to be able to test the hot half and the associated elements more quickly. Also, for obvious reasons, they would like less experienced employees to be able to manage the task without extensive training. Save time; save cash! This wish list also included
Minimizing Costs and Simplifying Hot Runner Repair
How will you minimize downtime and costly hot runner repair in your shop? The answer isn’t as complicated as you might think…here’s how Fast Heat by Spark Industries will help! You already know preventive maintenance is critical to the success of your shop. There will always be some amount of hot runner system repair, but if you keep on top of the preventive maintenance, your costs for hot runner repairs will be minimized…as will costly unplanned downtime. And the bonus results include more consistent high-quality part production and less material waste which translates directly into cost savings! You can avoid miswires, open circuits, and shorts by making a routine check of these a part of your PM Plan. Have your techs check cables, pins, and the individual elements
Injection Molding Best Practices:
What’s All The Hubbub?
In short, best practices are sets of methods and techniques that increase efficiency and develop structured processes with optimal results. Best Practices allow you to streamline procedures and stick to industry standards.
Fast Heat by Spark Industries assists those in the plastic industry in setting up their business for success by following Injection Molding Best Practices and by sharing how you can improve your company’s best practices.
Of course, since you’re here, you probably already know Fast Heat is all about optimizing hot runner injection molding best practices and processes with the utilization of their custom products.
However, just in case you’re new to the world of hot runner applications or injection molding, let’s just start off with a little basic review to get you in the zone:
To start, take a look at this Plastics Technology article that gives a succinct explanation of what a hot runner system is:
First, think of it as an extension of the molding machine itself. Its purpose is to keep the plastic molten at a proper temperature on its path to the cavity. So basically, it’s just a piece of heated steel with a round channel in it for the melt to flow through. Ideally, this channel would be running at the exact temperature on the controller, free of obstacles such as dead spots or components that could create hangups and cause scrap issues with color changes or contamination.
You can check out the full article in PT addressing hot-runner benefits, improvements, and everyday issues from the perspective of decades of experience, A View from the Bottom Up.
After you have examined these standpoints, pop over to peruse how Fast Heat by Spark Industries Hot Runner Controllers will help you achieve the consistency you need.
Another area of importance touched on by PT is heated sprue bushings and how they contribute to a uniform heat profile:
Switching from a Cold Sprue Bushing to a Heated Sprue Bushing
We know there’s really a lot of information out there. Who knew!? But, now you can make an informed decision. Examine Fast Heat’s offerings here and make your choice of Heated Sprue Bushings.
“Hold up,” you say, “not so fast.”
What, not quite ready to pick out controllers, sprue bushings, and Mold Boxes? Do you want to know more? Ok, you know what hot runners do…but why would you want to choose a hot runner mold in the first place…what does it mean for you and your business? No worries, we’re here with more substantiating info:
Top 5 Benefits of Hot Runner Systems:
- Allow a wider range of resin application
- Mold more complicated and detailed parts
- Higher throughput
- Lower labor costs
- Reduce scrap
You may also want to check out this article, “Seven Key Advantages of Hot Runner Systems”, by JOHN THIRLWELL, VP OF SALES AND MARKETING, CACO PACIFIC CORP., PUBLISHED IN MOLD MAKING TECHNOLOGY, where, among other advantages, melt flow…one of our favorites, is discussed.
Balanced Melt Flow
The flow advantage that hot runners have is that the melt channels are in separate, externally heated manifolds, which are insulated from the surrounding mold plates. Different from a cold runner plate, the hot manifold can be designed to have flow channels on multiple levels to ensure that the resin flows the same length from the molding machine nozzle to each cavity with the same channel profiles and diameters, number of turns, heat soak and pressure loss (see Figure 1). In other words, the plastic reaches each cavity – whether there are two or 96 – with the same pressure and thermal history. This designed-in temperature and pressure control is particularly favorable for resins that have narrow processing windows.
Figure 1: Balanced melt flow – a multi-level hot manifold gives equal flow and pressures to all cavities for equal filling
Now, you’ve read the experts’ views, and you’re finally convinced that you have some projects that make sense to convert over to hot runners. But you may also be asking yourself, “How am I going to accomplish this?” Once again, we look to the experts at Mold Making Technology, who provide a helpful summary on:
How to Transition from a Cold to Hot Runner Mold
Moldmakers and molders who use hot runner systems in their molds will be the first to disclose that it is often the most expensive part of the mold build. But they quickly add that it is worth the investment based on reduced cycle time, resin cost, elimination of post-processing, product lifecycle, etc.
Finally! You have your hot runner mold projects in place! Ok, we know it isn’t quite as easy as that…it will be a process…but once you do get your projects transitioned, you will want to know more about what Fast Heat can do for you. How are you going to benefit from Fast Heat by Spark Industries once you have decided to go with a hot runner tool?
Our Best Practices blogs will help answer how Fast Heat by Spark Industries will be of value, and you can check them out in their entirety with the provided links. We have also included some useful connections directly to our product pages. Of course, you can always CONTACT US with any specific questions.
Highlighting Injection Molding Best Practices | Fast Heat by Spark Industries
Hot Runner Temperature Controllers Boost Productivity and Quality
This may seem like stating the obvious, but if you can cover or “control” variables from nozzle to cavity, you are definitely reducing the likelihood of problems with your parts and everything in between. Mold manufacturers that install a quality temperature controller on a hot runner system will not only lengthen a mold’s life but will help improve part quality…it’s just that simple.
Fast Heat by Spark Industries will increase your efficiency and, ultimately, your bottom line.
Additionally, you can read about the Pulse Hot Runner Controller Pulse™ Hot Runner Controller and its related alarms in a troubleshooting menagerie that introduces some concepts such as “bake out” and why you need to address it in Troubleshooting.
Hot Runner Performance
Hot Runner performance is critical to maintaining production schedules and eliminating costly downtime.. Having the tools to ensure your hot runner performance is peak is where Spark Industries comes in.
Manny Diaz developed the MoldXChecker® as a result of feedback from customers who stated they would like to be able to test the hot half and the associated elements more quickly. Also, for obvious reasons, they would like less experienced employees to be able to manage the task without extensive training. Save time; save cash!
Manny Diaz, Managing Partner of Fast Heat by Spark Industries, and inventor of the CableXChecker® , was constantly running into the issue of showing up at companies to do maintenance and having no available cables to use to troubleshoot the hot half of the mold; the cables that were known to be good where always already in use on the floor.
And to avoid those Cable Connection Problems from the get-go:
You can accomplish some quick fixes… and one significant change with great results is to include 24-pin male and female connectors; unlike your 25-pin connectors, these 24-pin connect
ors are heavy-duty. The pins won’t bend or get pushed back and are rated for 16 amps. They also have screw terminations and are much easier to connect to mating mold boxes, cables, or controllers. Take a look at the original article for a detailed diagram of the Anatomy of a Connector MoldMaking Technology Article and further tips.
Fast Heat by Spark Industries has answers for all of your hot runner controller and hot runner cable needs. Make us your go-to guys. We are here for all your questions; it’s what we do!
The last Fast Heat item we want to share with you today is regarding screw tip assemblies. Material and Design are key elements of consideration, and there really aren’t any BAD tips, per se. But you have to figure out what tip is best for your specific job. What resins are you running? What material is your tip going to be made of, and what type of design is going to benefit you most? Fast Heat can help! There are literally hundreds of options out there from which you can choose, but we encourage you to take a look at these manufactured by Zeiger Industries, Screw-Tip Assemblies.
Here at Fast Heat, we look at publications like Plastics Technology and Mold Making Technology for guidance in all things plastic. We want to add one other PT piece we think you may find valuable, Tips to Help You Succeed with Hot Runners. Having said that, we have thrown a lot of information at you, and we had you roaming cyberspace to and fro…but, in the end, we think you will agree that Fast Heat by Spark Industries is also a great resource. For all things related to Injection Molding Best Practices, we want to be your 1st Resource!
Check Out Our Productivity Series!
- Processing with Hot Runners – https://fastheatbyspark.com/
hot-runner-injection-molding- process/ - Electrical Consumption of Hot Runners – https://fastheatbyspark.com/
hot-runner-kw-demand/ - Troubleshooting Hot Runners – https://fastheatbyspark.com/
hot-runner-troubleshooting/ - Hot Runner Maintenance https://fastheatbyspark.com/
hot-runner-maintenance-guide/ - Injection Molding Cell Integration of Hot Runners – https://fastheatbyspark.com/
hot-runner-control-input-and- output-communication/
