Category Archives: Fabrics

Custom Creative Solutions

Posted on by W.F. Lake Corp.
30 Jun

We get some interesting opportunities here at W.F. Lake Corp.! I’ve touched on many of our unique capabilities in our PTFE coated fiberglass sewing thread operation, where we can twist in wire with Kevlar* or fiberglass, make colors of fiberglass yarns, make colors of braided PTFE coated fiberglass draw cords, etc. Today we’ll take a look today at some of the interesting PTFE coated fiberglass belts we manufacture.

We sometimes refer to Custom Products as PTFE coated fiberglass belts (or commonly Teflon* coated fiberglass belts), but they really are custom fabricated combinations of materials designed for unique applications. All of this starts with a conversation, and that conversation usually begins with “can you guys make something that will ‘fill in the blank’??”. Our unique capabilities in our belt department enable us to combine materials in unique ways to solve tricky problems.

For example, we make a “Rotary Kiln Seal” that combines PTFE coated Kevlar*, PTFE coated fiberglass fabric, and PTFE coated fiberglass sewing thread into a high temperature gasket for a rotating kiln. This seal had to operate in a high temperature and high friction environment for months at a time.  The fabric provided reduced friction against the hot face of the rotating kilns while the Kevlar* worked to reinforce the outer face. Of course, our fiberglass thread held it all together at extreme temperatures.  This kiln seal did not look anything like one of our PTFE coated fiberglass mesh belts, but we used those same capabilities to make it happen.

In another case, a customer asked if we could put “cleats” on a PTFE coated fiberglass belt. Cleats? Sure, but what are we going to make those out of those? This belt had to operate at 500 deg. F in a curing oven. Operating temperatures of 500 degrees Fahrenheit rule out most belting materials, but not PTFE coated fiberglass.  Still, we had never put cleats on one of our belts. Interestingly, the cleats were needed because this belt was required to run up a slight incline and product would slip down the belt if no cleats were installed. So, we made up some samples and settled on standing cleats 2” tall made with layers of PTFE coated fiberglass laminated together (essentially a small board of PTFE coated fiberglass). We bonded and sewed those cleats to a belt material and the problem was solved!

I could go on, but the point is that when it comes to PTFE coated fiberglass belts (or custom fabricated products) we are able to combine our unique processing capabilities with the wide range of materials we manufacture and come up with some pretty creative solutions. Since we perform all these operations in-house, ideas turn into samples quickly. The best of those ideas and samples often become unique products to solve your most demanding application needs. Give us a shout or zing us a note and we’ll get the ball rolling!

Color of PTFE Coated Fiberglass Fabrics, Tapes, and Belts

Posted on by W.F. Lake Corp.
12 Apr

PTFE Coated fiberglass fabrics, tapes and belts are typically a tan color.  Within the industry, we call this color “Natural”. But if you’ve ever worked with fiberglass fabric (maybe to repair your car or boat), it looks white. And of course it is white until it sees heat, then it turns “tan” or “natural”. Read on if you’d like to find out why!

Fiberglass yarns are made up of very fine filaments of glass fiber. These filaments are amazing little things, but they are, after all, glass and are subject to damage or breakage like any glass product would be.

Imagine very fine fiberglass rods; they’d easily snap and break if not handled very carefully. In order to make fiberglass filaments more durable, a starch “binder” is applied to the filaments to protect them in further handling, braiding, twisting, weaving, etc. These binders are organic… in some cases they are potato starch!

These binders caramelize when they see heat, very similar to a piece of toast turning brown in your toaster! Of course, PTFE coating of fabrics, tapes and belts requires relatively high temperatures to cure the PTFE. That tan color from the binders being heated is then trapped within a translucent PTFE coating, thus making the final product “tan” in color.  We call it “natural” because it is what naturally happens to these binders. You may see slight variations in the tan/natural color of the product because different binders are used on different yarns.

OK, but why are some black in color? That’s because we sometimes add pigment to the PTFE dispersion to achieve different colors or characteristics. Black is often used for several reasons. First and foremost, it is used to pigment belts in ultraviolet curing ovens (most often in the screen printing industry). When under UV lights, the starch binders that make a fabric or belt “tan” will bleach out, turning your tan belt a funny shade of off-white.

Although this in no way impacts the performance of the belt, it is often perceived as a failure. In order to hide that change, we make the belts black. That same black color can mask other things like wicking oils in food processing, ink from screen printers, etc. In some rare cases, specialized pigments (mostly black) are used to try to impart a degree of conductivity to this incredible insulator. In most cases, the point is to create a path to discharge static electricity.

What about other colors? Sure, they can be done but really are very specific to certain industries and not typically an issue in most commercial applications.

Yarns for electrical insulation are an entirely different beast, Yes, we manufacture those as well, but they are another topic entirely!

Again, and as always, contact us with any questions or comments. We’re here to help!