I’ll discuss different types of guides and recommend our favorite, ceramic!
Choosing the right yarn or thread guide for the product and process is one of the key factors that can influence the quality and efficiency of any production operation using industrial textiles. In my role as maintenance manager at Service Thread, I have learned (sometimes the hard way!) to look at yarn guides and thread path first when operators report problems.
What Yarn & Thread Guides Do
Guides are generally used for directing or positioning ends of yarn, thread or wire for processing on production equipment, and may also add tension to the yarn for processing.
Thread Shapes, Sizes, Materials & Surface Finishes Shapes include eyelets, pigtails, rods, discs and others. Sizes can vary from very fine, typically used for small gauge threads, to large sizes designed to minimize tension or accommodate multiple ends of heavy denier yarns. Materials used for guides include steel and aluminum alloys, ceramic and porcelain.
You can identify a guide’s materials or type by color:
- AP (alumina pink): This is a higher quality alumina oxide, 95 to 99.7% pure. Long lasting, the 99.7% pure ceramic material is commonly available in various surface finishes, making it easier to find a ceramic to fit your applications.
- AR (alumina red): This is a deep red material, of 85% purity alumina oxide. With low density and low hardness, it is a general purpose ceramic.
- AW (alumina white): This material is white in color. This can be alumina or 95% pure zirconia, and is suitable for general applications.
- T (titania): This material is tan in color, and has been used for many years. 90% pure material, this is a soft ceramic which wears with the yarn, for applications where yarn damage is minimal.
- TBR (titania brown): This is titania material, similar to 90% pure titania, in a slightly browner shade.
- TC (titania conductive): This material is dark grey in color, and has been widely used for some time. It is the same 90% pure titania, but it is fired with an additive to make it neutralize electric charge. For applications where static is a problem, the nature of this material can be helpful.
Chart courtesy of Eldon Specialties
Guides also have different surface finishes. For example a metal guide can be chromed, ceramic coated or have a black oxide finish. The different finishes can cause more or less drag on the yarn. A satin or MF (matte finish) has an orange peel appearance and will have less drag than a bright chrome finish because the yarn is running over small peaks and valleys compared to a flat surface that has a larger surface area. A DP (diamond polish) surface finish is heavily polished and finished to a smooth texture, ideal for use with textured yarns in the twisting and heating zones. Ceramics with this finish are also great for use as interlacing jet entrance and exit guides.
Are You Using the Right Guide?
Choosing the correct guide for your application is critical to ensure quality production and process control. Machine manufacturers for thread and yarn processing machines may not always choose the best guide for your application. This is because most machines are designed with general processing in mind, and cheaper guides are often considered wear items that can be sold as high margin replacement parts.
Benefits of Ceramic Guides
Ceramic is always a good choice because it offers the best wear, heat and chemical and corrosion resistance for most applications. We use ceramic at Service Thread for most applications since we get long wear and minimize yarn damage as the high processing speeds we run.
If you have questions about what guide selection might improve your process, you can contact me at any time. At Service Thread, we believe in sharing our ‘Best Practices” learned from processing virtually every size and kind of yarn fiber known. We are here to help!