Mount Vernon's World-Class Slub Yarns
Customer-driven spinner services diverse markets.
By Eric Vonwiller, Technical Editor
ATI recently had the opportunity to talk to plant management about the company's specialty yarn manufacturing division and to get a glimpse of what makes it so successful.
Today, the company is composed of six divisions, of which the Yarn Group is one member. The Alto plant was built in 1967 as a supply-spinning mill for the LaFrance division. It was set up primarily for ring-spun rayon yarns.Over the years it produced mostly rayon yarns. More recently cotton processing was introduced. Today, the mill produces 100-percent cotton yarns, 100-percent rayon yarns, and plied combinations of cotton and rayon yarns.
Mount Vernon's involvement in slub yarn manufacturing dates back nearly 40 years at plants in Maryland and Maine. The company was one of the original producers of 19/1 rayon slub/nub yarn.This product remains an active style even in today's market, but Mount Vernon no longer produces it. Mount Vernon maintained slub manufacturing capacity as it moved south, adding slub equipment to ring spinning at the Columbia operation and ultimately at Tallassee, Alabama.
"The Pamplins are very supportive owners," said Charles L. Little, president of the Yarn Group (yarn sales division).
Little became yarn merchandising manager in 1988 and took over yarn sales. In 1995, he was named president of the Yarn Division.
"We can feel the true desire for growth and investment that the owners have in the business," he said.
What counts for Mount Vernon today is its commitment toward customers and the continuous investment in technology. Investment in the Mount Vernon Mills family is often an expansion or modernization valued in the tens of millions.
Currently, there is a $30-million expansion under way in Cuero, Texas. Continuous investments are going on in all of the company's plants.
The Tallassee plant historically made slub yarns. In the early 90s, ring-spinning was removed from Tallassee with Alto adding new slub attachments to its ring spinning. One of the major modernization programs was started in 1990 with all new Murata winding and Saurer-Allma twisting.
By 1993, the plant expanded again, nearly doubling its original output. This included replacing all cards with Trutzschler DK series cards, electronically controlled Rieter RSB 851 drawframes and Schlafhorst SE9 rotor spinning frames.
The next, and most significant step, as Little sees it, was to replace older ring-spinning frames with modern, automated ring-spinning systems.
This includes linking Marzoli roving frames, Suessen Fiomax 1000 ring-spinning frames, and automated Murata Link Coner winding.The integration of the Amsler slubbing device gives the company the extra edge to produce, at will, effect yarns for customers.
Electro-Jet did the automation for linking Marzoli's roving frames with Suessen's spinning frames, while Luwa-Bahnson provided a modern air-handling system.
Plant Manager Mike Godfrey had only praise for all the company's suppliers, though they admit that things were not always easy at start-up. Some of the installed technology was new to the United States, and that is always a challenge for the mill and the supplier. However, the result appears to be performing well.
According to Charlie Reed, who is responsible for the quality assurance in this plant, the effect-yarn capability on the ring spinning frames has not been developed to its full potential.
Little mentioned that they did not choose to purchase equipment from only one vendor, especially in the area from roving to spinning. "We actually chose the all-world package," Little said.
One Marzoli roving frame is designated for rayon and four frames are selected for cotton production. Electro-Jet provided the automated linking system, which connects the five roving frames with the 14 Suessen spinning frames. It's a very versatile system, said Godfrey of Electro-Jet's installation. "You insert the creel fully into the spinning frame, and then the empty bobbin is processed through the bobbin stripper and then back to storage. It's also a simple system and very dependable."
The Alto facility was Electro-Jet's first automated transport system in the United States. The advantage of this system is the battery-operated Auto-Motor monorail setup, which allows for high efficiency without the need for a complex infrastructure of pneumatic lines and extensive wiring. All functions are controlled by a host computer, and the battery-operated unit controls position constantly using on-line sensors. The system maintains full control over handling two different raw materials - rayon and cotton.
From Marzoli's roving frames, the Electro-Jet system allows transport and direct insertion into the creel of the ring-spinning frames. Suessen's Fiomax 1000 ring-spinning frame is equipped with the CutCat Whorl Cleaner, automated doffing and an interface for linking each of the 1,008-spindle frames to the Murata winders.
Amsler supplied the electro-mechanical device for slub formation, the central control unit and the slub programming unit on the ring-spinning frame. The Amsler slubbing device allowed for the development of new products and the innovation continues. Even rayon was moved into the slub arena to expand the product line.
"We purchased the Amsler equipment because it was proven equipment for very long link-spinning," Little said. "We have had great success with the former Murata winders, and, we chose Murata winding once again."
There are 32 position winders for clip-cone and conical winding, plus dye-tubes are run on these winders as well. As one of the final stages in the plant, Xorella Yarn Conditioners were added as the final refinement stage for cotton yarns. Conditioning for cotton is automatic. Weaving customers have recognized the benefit conditioning imparts.
Quality is assured in several stages of the production process. Zellweger Uster has provided instruments and equipment for quality control. In the textile lab, AFIS is used to analyze fiber materials; Usters UT-series evenness testers are used for sliver and yarn testing; and a Classimat and single-end tester provide all necessary yarn quality data.
According to the company, an investment in the new Tensorapid will take place within the next few months.
On the actual production floor, Zellweger's Polyguard yarn clearers are installed on Schlafhorst's open-end spinning frames, while P551 yarn clearers perform their tasks on the Murata winders. Zellweger's P830 serves as a monitoring system. Little emphasized the effectiveness of the Luwa-Bahnson air conditioning system, which was put in place while installing the new frames in the ring-spinning area. The challenge was to keep the mill operational while the new spinning frames and return-duct system were installed.
Little and Godfrey compare this system to three other manufacturer's systems throughout the plant, and they say Luwa-Bahnson's system does an outstanding job. Luwa installed rotary prefilters and rotating screens, based on the principle of a two-stage filtration system. Therefore, it is most efficient to separately capture coarse waste in the first stage, such as thread pieces, and fine dust in the second stage.
The prefilters function on a higher air velocity than the second stage dust filter. All waste is automatically doffed by a waste collection system. Lint, in this kind of operation, is a major factor to figure into the air filtration system. A deviation diffuser permits distribution of the air at a very slow velocity. The plant also received new air washers, and a high air exchange rate was selected because of coarse count yarns. The installation is now well ahead of all OSHA standards.
Historically, Mount Vernon has always been involved in the upholstery and home furnishing fabric trade, which is still very much a concentration of Alto's sales yarn effort. Currently, all of the rayon production is sold to other manufacturers. None is used within the Mount Vernon Company.
Many varieties of yarn packages are offered to clients, exactly as the customer requires them. Alto itself has no yarn dyeing operation, but supplies a vast variety of different yarn package setups to its clients. Little mentioned that there are numerous shapes and sizes of dye packages, and each dye package customer has its unique setup and specifications.
To date, the primary focus has been on coarse-count yarns, but product developments point toward an expanded cotton count range, plus rayon slub yarns. To take full advantage of the equipment, Mount Vernon has retained the services of Per Olsson of Sweden to assist in developing its home furnishing product offerings.
Olsson is a highly regarded consultant in the slub yarns area, with a full understanding of the Amsler equipment and its capabilities.
Little envisions that more and more of the plant's production will become value-added slub products.The Amsler system adds character to yarns in a controllable manner with repeatable physical yarn characteristics. Denim, for example, is a major segment for Alto's slub yarns. Engineered slubs give denim the character of old, traditional denim when woven into fabric.
"Some of our customers have 100-percent warp slub yarns and 100-percent filling slub yarns in the fabric," Little said.
And you often will find customers that will do one end of slub cotton and one end of smooth yarn alternating in the warp direction. In filling, customers may use an end of slub yarn among several yarns selected or use 100-percent slub.
Applications of cotton slub yarns in knitting are cotton sweaters and hosiery. Boot socks for outdoor activities are a typical application.Traditionally, this plant concentrated on the coarse yarn count range, but is now moving toward a finer count, which is made possible by the investment in the modern equipment.
The company's philosophy is to work closely with customers and to reply to customer requests in the shortest possible time. For example, Little mentioned that a customer called in an order for 12/2 yarns, which is not a standard item in Alto's manufacturing program. By the next morning the yarn was in production.
"This is the response time our customers are looking for, and this is what we deliver," he said.
The plant is trying to offer value-added products as close as possible to commodity yarn prices, according to Plant Manager Godfrey. Mount Vernon is committed to meeting large- or small-quantity orders, and everything is treated with the same priority. Yarn count changes are commonplace, however, only a small percentage of equipment is subject to these changes.
"Our goal is to have the best slub yarns on the market," Little said.
Little sees the success of Mount Vernon's Alto plant as the result of modern equipment and the training of plant personnel.
For Mount Vernons Alto yarn operation, success starts with the choice of a premium fiber, continues with delivering value-added products and ends with implementing customer feedback.