SOUTH GLENS FALLS, NY,
March 13, 2009
(Press Release) -
A single load cell has made a significant difference in the operations of a web forming machine sold and serviced by Glens Falls Interweb, Inc.
Glens Falls Interweb, Inc. (GFI) focuses on the design, specification, and manufacture of custom equipment for the pulp and paper, specialty papers, and wet laid nonwovens industries on a confidential basis. The company specializes in cost effective engineering, equipment, machine design, process improvements, and innovative solutions for customers.
In 1998 Glens Falls acquired the DeltaformerTM technology from Metso when it acquired Metso's wet laid nonwovens business. The DeltaformerTM is an inclined wire former designed to produce a continuous web of fiberglass mat for roofing material, and other nonwoven materials. Many of the machines that GFI services are Sandy Hill DeltaformersTM. On one such machine, maintaining proper fabric tension had become an issue. The installation of a Montalvo load cell provided the tool necessary to maintain optimum fabric tension throughout the life of the fabric. This translated into improved machine performance, uptime, and reduced maintenance and repair costs. The rolls used in this application are 120 inches wide and the line runs at about 600 feet per minute. Previously the machine had no load cell and tension was measured by eye, feel and operator experience.
The addition of the Montalvo U-Series load cell resulted in reduced downtime, longer fabric life, higher product quality, and greater consistency in the final product.
The problem: prior to installing the Montalvo U-120 Series load cell, the wire carrying the material experienced premature failures, resulting in higher costs and greater downtime.
Ray Stevens, applications manager at Interweb, says, "The machine is now performing very well and we expect a decrease in the failure rate of the wire."
Stevens says the installation took less than one day. "We had to make an adaptation of about 2.6 inches to the height of the centerline of the roll and create a new bearing housing holder. We also found the length of the load cell interfered with the scraper (doctor blade) and needed new mounting brackets so the doctor would clear the end of the load cell." GFI, in conjunction with Montalvo engineer Larry Jones, formed a problem-solving team. Montalvo evaluated the application in terms of tension requirements and forces realized by the equipment and assisted with installation and set-up. The team did all the engineering on site to accommodate the new load cell including calculating the bearing height, building new idler roll stands, incorporating adapter plates and the mount for the load cell, and locating the shaft into the pillow block bearing (the U-120 load cell is located under the bearing).
The U-120 was the perfect load cell for the system. With its all-stainless steel construction and IP67 rating, it will hold up to the harsh environment in which the unit was installed.
Ed Montalvo says the U-120 load cell is the largest load cell Montalvo currently manufactures. "And it is waterproof, made to operate in wet and corrosive environments," he adds.
Stevens says being able to accurately measure and maintain fabric tension on a continuous web forming machine is critical. Tension must be high enough to provide drive transmissibility and adequate guiding of the fabrics. However, if tensions get too high the results may be reduced fabric life, premature roll, journal and/or bearing failures. "Periodically, a customer will inquire about adding tension measurement which is generally done by using an electronic load cell mounted on a roll or under a bearing housing of a roll. It was for this purpose that we contacted The Montalvo Corporation."
Taith Rupp, in Montalvo's sales department, says the wire involved originally had to be replaced every four to six weeks at a significant cost and tension had traditionally been adjusted manually. "But," he says, "the delay in adjusting the tension that way is often too long and the damage is done before any correction can be made to the fabric tension. The wire gets stretched and the quality of the product is diminished -- it's too stretched or too thick. If it's too stretched, the product can get sucked into the wire and plug it up. The Montalvo load cell changed all that and provides accurate, repeatable tension, and a consistent product."
Rupp says the installation at GFI included one U-120 Series load cell with a 20,000 pound capacity, and a Montalvo I-3200 tension indicator. Rupp says, "The typical application requires hanging weights from rollers to calibrate the load cells. Hanging more than 5,000 pounds for calibration is a safety risk so I turned to our engineering and electronics departments. We discussed the customer's needs and came up with a software solution that enabled us to offer them a ‘weightless calibration system.' We perform a complete analysis of the load cell and are able to accurately perform calibration without applying any weights to the sensing roll. The reliability of this process lies within Montalvo's load cells' extremely low hysteresis and high-repeatability levels. These are a direct benefit of semiconductor-based load cells."
Rupp adds, "At a time when paper and non-woven manufacturers are under heavy pressure to reduce the cost of operations, Glens Falls Interweb and Montalvo have engineered a system that enables them to do so. Cutting costs associated with wires and felts is a critical strategy that is leading to many advantages in the industry."
The calibration software for the installation was developed by Montalvo software engineers and electronic specialists.
G. F. Interweb customers include the Ahlstrom Filtration, Lydall, Kadant AES, METSO, Saint Gobain, and others.
