Effectively Getting to the Root of the Problem

Diagnostic device helps molders check hot runner cables quickly and efficiently

CableXChecker

Spaghetti bowl?!

That’s right…spaghetti! That’s what all the wires and cables inside a press might remind you of…and have you looked closely at all the pins and cables making up a hot runner system?

Plastic injection molding is not for the faint of heart…it is both an art and a science. Hot runner injection molding involves lots of cables, wires and moving parts; these things are sometimes confusing and temperamental. Understanding and repairing this essential equipment is a big deal!

So, how do you make the best of trouble shooting this often complicated equipment?

First, we want to point out the obvious…that preventing issues is the best way to avoid unplanned down-time.

Yes, preventive maintenance is key but you know that doesn’t mean you can avoid every possible issue, unfortunately. But, having the proper plans and tools in place for those unforeseeable incidents will help save you time and money…not to mention frustration.

If not done effectively, your maintenance crew and techs could spend days attempting to find the problem with your press, hot runner controller and all other auxiliary equipment…literally thousands of possible check-points exist and there is no way you or your technicians can check every single one of them.

We know…that sounds a little dramatic…but it is true. Go ask one of your maintenance staff if they have ever spent hours upon hours trying to identify a problem only to find that it was a loose or shorted cable. It happens and it has likely happened to the most experienced and to the most green of your staff.

So, when your crew needs to figure out a problem, how do they attack it so that countless hours aren’t wasted? The answer is to use the right diagnostic tools and apply a systematic process.

Our focus is diagnosing potential hot runner system issues to find the root problem.

You can diagnose power and thermocouple cable issues in an instant with CableXChecker.

CableXChecker provides an easier, one step check. The CableXChecker, by Fast Heat Inc., enables maintenance technicians to cycle through a 24-pin cable in less than one minute. A systematic process of elimination is necessary; test the cables, then you can move onto the mold. It also allows you to test and verify your cables before setting up the process; check cables before they are installed on the mold in order to prevent production downtime.

Learn more here about the CableXChecker system here:

Diagnose the Root of the Problem Effectively

Real case scenario: The Perfect Storm

A hot runner, 8 cavity mold is being ran on your production floor and the press operator tells your shift supervisor that the parts keep kind of…”dangling from a string” upon ejection. In fact, the mold has just closed on one dangling part and caused an alarm.

Ok, so your supervisor cancels the alarm and examines the mold for damage…luckily, no damage. The press runs through a few more cycles and they see that the material is stringing at the gate just like the operator noted.

In the meantime, the shop ops manager has seen on the real-time schedule that you have a press down and decides to pop out on the floor to see what the problem might be. The customer has called twice this week and their production line is down without these parts…and the customer can’t have any further delay. These parts must go out the door today! Ah, the joys of custom plastic injection molding.

Now, you may be thinking, “this is worst case scenario and it rarely happens like this…” or you may be thinking, “this isn’t a big deal…happens every day…fix it, or just move the job to another press.”

No can do…you are at full capacity for the 200-ton presses on the floor.

Your tech needs to check all the usual suspect problems that would cause stringing but it will be a quick fix, right?

The initial conclusion is that the material was seemingly too hot and causing the stringing. No, sir, the set points were within the suggested range for the material…the same set point you always use for this job. Ok, so maybe there are thermocouple problems? Certainly possible.

Luckily a seasoned tech grabs his hand-held laser thermo and finds that the actual material temperature is much higher than what the read was.

(But, in the meantime while these considerations are being made, QC and the material handler have caught wind of the scuttlebutt and are now getting involved to try to identify the problem. Is there moisture in the material? Maybe the dryer isn’t working properly. Oh no…maybe it’s contamination…that could be. Now, you have at least 2 or 3 more employees considering what the cause is and they could have been working on other projects.)

This is how it happens…we have seen it. If you have been on enough production floors, you have seen it too. An hour or more has passed just considering the first few root causes and it isn’t so unreasonable really because all possibilities have to be considered, tested and eliminated.

Seriously, what do you do? Test the material for moisture? Rearrange your schedule for a different press to be used? And what will you tell your customers? Sorry, you are just not going to get your parts on time? You know that’s not going to fly.

All of these answers are going to cost you! And your customer is chomping at the bit for this order.

The thing is, it isn’t the technicians’ fault…yes, sometimes we miss something or make an error. But often it is just a simple answer but that could take a good amount of time to figure out.

In this case, the way to correct the problem seems to be to set temps at about 40 degrees below the suggested limit for the material. Which the tech does and production gets back on track.

However, ensue the perfect storm scenario…something crazy happens with the color feeder right at shift change and when the press is brought back on line and production starts back up…the night shift tech starts to experience the stringing again. Why? Because the actual root of the problem wasn’t identified and corrected.

So, the whole troubleshooting process starts all over again.

The outcome of this “perfect storm” found that a thermocouple cable had a short or break and was only sporadically causing an issue.

This is a real-life scenario for any shop. The resulting delays in production and the having to repeat much of the troubleshooting could have easily been avoided with a simple diagnostic device for the hot runner control system.

The Fix: CableXChecker

With CableXChecker, you simply plug it in and turn the selector switch from zone to zone; it tests the continuity of the entire cable. Your shop can check thermocouple cables and power cables in just a minute or two. Eliminate or prove cable or plug failure in a couple of minutes instead of the 30 to 45 minutes it takes to check, pin for pin, each end of the plug.

Ideally, the best situation would be that you would have your techs utilize CableXChecker before set-up and start-up. A good start-up will lend to a better production run every time!

The CableXChecker is a custom device that can be applied for use directly on the manufacturing floor or in any maintenance shop. It will undoubtably save your shop time, money and aggravation.

Check out this quick video to see just how simple it is! https://youtu.be/v8nAXDuQeVw