Better temperature control delivers higher productivity and quality as well as significant raw material and energy savings.

Soaring energy and healthcare costs in the United States are apparently here to stay, according to leading economists. When one considers this, along with the ever-increasing foreign competition, it’s difficult to imagine manufacturers who are on the bubble surviving through the end of the decade.

According to John Engler, former governor of Michigan and now president of the National Association of Manufacturers, U.S. manufacturing is at a staggering 32.5% disadvantage to foreign competition due to:
  • Regulation
  • Litigation
  • Energy
  • Benefits
  • Taxes
Clearly, the manufacturing manager does not have control over many of these business costs. If some of these companies would explore better process control through temperature measurement, however, they would very often find relief.

Fig. 1. NANMAC smart ejector pin thermocouple

Injection Molding Benefits

Interestingly, it tends to be the companies that are highly profitable and leading innovators that are focused on higher efficiency. This is understandable because expensive projects cannot be undertaken by a troubled company. However, many of these projects require nothing more than consensus, $500 and a few hours of engineering. Now that NANMAC is offering proven solutions to plastics manufacturers, we’ve had a number of companies step up to the plate, and quite a few of them are getting a return on their investment in the first week. If this seems impossible, consider the following example from the injection-molding industry, which is fictional but based on reality.

Case Study #1
A2Z Molding Company makes plastic golf tees that are supposed to add 25 yards to the average drive. A new marketing campaign has increased orders, so manufacturing of the super premium golf tees is in “full swing.”

Unfortunately, about 5% of the tees are rejected for aesthetic reasons by one of several inspectors. Currently, these are sent to regrind and then are reprocessed along with virgin material. Here’s what we know about the rejected parts:
  • Each one carries a labor cost.
  • Each one has different physical properties than virgin material, including shape, color and strength.
  • Each one carries overhead cost in terms of energy and machine time as well as total project time or time to ship.
  • It’s good we caught them instead of our customer.
What if we could lower the reject rate to less than 1%? It doesn’t take a genius to see that 80% of labor cost associated with QC, in addition to energy, time and future rejects, could be avoided in this higher-efficiency scenario. But what was the solution? More importantly, what was the investment? When will it be fully paid back?

In the case of the smart ejector pin thermocouple (Fig. 1), we’ve not had a customer who didn’t get an ROI within one week. In other words, it’s a no-brainer. Here’s why. By adding an “ejecto-couple” in the mold cavity, we can cure parts more consistently, regardless of process variations, by using temperature instead of time. In the end, fewer parts are over or under cured, and in most cases cycle time is reduced. These savings can go into the multiple thousands of dollars per week, even before you consider such savings as: longer setup time, health insurance for extra inspectors, the cost of missing a ship date or incurring a customer return.

And yet fewer than 1% of injection molders in the U.S. are buying our smart ejector pins. You may find it interesting that many who are buying these handy devices tend to be in other countries and, in many cases, are the category leader. They know that ROI is quick because of the low initial investment, and NANMAC helps with the engineering work at startup.

Fig. 2. NANMAC spring-loaded thermocouple

Case Study #2
Here’s another example, also in the field of plastics. This time we’ll pick a fictional automobile seat manufacturer. During the manufacture of plastic coverings for car seats, several layers of plastics are laminated together by heated stainless steel rollers. If the temperature of the rollers changes, many yards of material may be only partially bonded or perhaps not bonded at all. At 4-5 feet in length and 30 feet per second, this can lead to a lot of scrap.

The solution this time is a spring-loaded contact thermocouple that can make contact with the roller at one end, sense the temperature and connect to an alarm or roll-heater unit (Fig. 2).

Fig. 3. NANMAC rotating-drum and disc thermocouple

Case Study #3
This example involves the plastic coating of wire and fiber. While passing through a pre-induction heater at upwards of 3,000 feet per minute, you quickly get a pile of scrap if the wire is not heated to the correct temperature. The same applies to fiber processing.

The solution this time is a direct-contact thermocouple that can sense the temperature of the fiber or wire. Again, this is an inexpensive and quick fix.

We could also have picked foods, gases, petroleum products and, of course, metals. The bottom line is Arrhenius was right – temperature matters. Chances are, temperature is wreaking havoc in your process, and you can make gains by better temperature measurement and proper corrective actions based on that information. The question is only “how much?”

The answer is different for every company. You need to quantify the benefit of better measurement and control of temperature. A smart ejector pin thermocouple might save you three seconds of cycle time, which may not sound like a lot, but in this case adds up to 10 hours per week.

These three thermocouple designs are unique to NANMAC. They can be customized for a specific process and inventoried until ready for shipment. And these reliable and long-lasting sensors are still made in the U.S.

Consider what you can do with the information our sensors give you. An alarm is great, but full control based on the direction (vector) and amplitude (scalar) of the temperature measurement is how you will gain the most return on your investment.

Smoothing your process will result in fewer rejects, better mechanical properties and shorter setup.

So when you hear words like “custom,” don’t immediately think, “That’s expensive. I cannot afford it.” Consider whether you are losing precious things like raw materials, energy, time and profits, because in this world, companies do not enjoy “state-of-the-art” technology advantages for very long. Think about it, and then act decisively. That’s how you’ll keep the flame lit.IH

For more information:For over 50 years, NANMAC has specialized in difficult and critical temperature measurement for industry, defense and aerospace. Recently, NANMAC increased their capacity to serve the increased demand for JIT supply. Contact NANMAC Corp., 11 Mayhew St., Framingham, MA 01702; tel: 1-508-872-4811; fax: 508-879-5450; e-mail: info@nanmac.com; web: www.nanmac.com