Giving a Boost to Fabric Production
An industry leader in decorative jacquard fabrics was experiencing delays and quality issues on its 12.5-million-yards-per-year production line for coating woven textile cloth. The company called Advanced Energy, and our leading industrial process specialist, Mike Stowe, was happy to take a trip to look for opportunities to improve production and save energy.
To understand the challenge the site was facing, Mike conducted multiple site visits to observe the production line. Woven textile fabrics require a variety of coatings on both sides: the finished side and the back side of the cloth. Typically, the finished-side coating is a stain guard, and the back-side coating helps the cloth adhere to a substrate, like a foam cushion, during final assembly. The speed in linear yards per minute to coat and dry this cloth is the key factor in profit margins.
Unfortunately, due to the moisture content of the coating material, the plant’s quality expectations were not being met with one pass through the drying equipment. The plant was forced to run all double-coated cloth through a natural gas convection drying oven two times, once for each coated side. This setup required two overtime shifts on Saturday, extra runtime for the drying oven and double handling of the cloth — equating to more money spent and energy consumed to produce the coated woven textiles. Over a year, the plant used about 4.9 million kWh to operate.
The plant had limited space for additional drying equipment on its line, but Mike evaluated the possible solutions and recommended adding an infrared (IR) booster oven between the two coating stations. This IR heat would kick-start the drying process of the first coating before the second coating was applied. The second coating could then be dried at a higher speed rate through the existing drying oven.
By adding an IR booster oven in-line between the two coating applicators, the cloth could be processed in one pass through the drying oven. The first coating would be applied; the first coated side would pass through the IR booster oven and start drying; the second coating would be applied; and finally the double-coated cloth would pass through the drying oven.
This new arrangement would cut the coating drying time in half for all the double-coated products. The IR booster oven had the potential to save over 1,300 production hours per year compared to the existing drying oven. The site would see over $47,000 a year in net energy savings and could eliminate weekend overtime shifts, with an estimated annual labor savings of $420,000.
Purchasing new equipment is a big investment, even with the projected figures the site was hoping to achieve. Researching options, the plant determined that obtaining new equipment was not realistic given its budget for expenses. Instead, it was able to acquire a used IR booster oven for a fraction of the cost. Although the used oven did not exactly match newer models, it would have a similar impact on energy usage and production efficiency.
After installing the IR booster oven, the company saw immediate results. The reduced drying oven runtime is estimated to save 65,000 kWh of electricity per year (around $4,000) and 6,500 dekatherms of natural gas per year (around $43,000). Overall, the plant’s energy intensity in kWh per linear yard of cloth decreased by 12 percent, with project payback taking only one-third of a year. The combination of an electric IR booster oven with a natural gas convection drying oven produced a good solution for this problem.
Mike’s consulting remains today with the company. He is working to review other systems to find additional industrial processes that can be improved. Long-term financial and energy savings will hopefully continue for this fabric manufacturer.