Precision weighing technology increases accuracy
When the University of Wisconsin’s dairy department updated its mixing system, the switch to load cells helped produce a more consistent product.
The University of Wisconsin-Madison Babcock Hall Dairy Plant uses a hands-on approach to research and teach cutting-edge dairy science techniques to its food science students. The plant also turns 2 million pounds of locally sourced milk, including some from the university’s own herds, into ice cream, yogurt, fluid milk products, butter, cheese and fermented products.
The plant was built in 1951, making it the oldest university dairy building in the US. Planning is underway to fully renovate the factory by 2018 and outfit it with the latest industrial technologies. Part of this renovation is the updating of the old mix processing vats, switching from side-mounted pressure gauges to load cells for monitoring and controlling manufacturing processes. The production method requires monitoring the level of each ingredient before it is added to a mixing vat and then passed along the production line.
“In the past, we measured the liquid levels either by pressure sensors or measuring sticks and had to adjust for product density,” explains Plant Manager Bill Klein.
Load cells were recommended due to their potential for greater accuracy, producing more consistent ingredient mixtures and cost-effectiveness. The tanks the plant chose were designed and built by Sprinkman Corporation; the load cells were supplied by Sartorius Intec, a manufacturer of industrial technologies headquartered in Hamburg, Germany.
The Sartorius Intec PR 6211 compression load cell was chosen in conjunction with a PR6011 flex-lock mounting kit to fulfill the plant’s requirements. Available in versions from 500kg to 10t, the cell is fully constructed from stainless steel and allows for calibration without weights, simplifying the installation. The X5 system controller was installed alongside the load cells and mounting kits to accurately control the plant’s manufacturing processes.
Using precision weighing technology in production processes offers manufacturers the chance to greatly increase the accuracy of their systems and reduce product giveaway and inconsistencies. Babcock Hall Dairy Plant’s original system relied on volume; however, with a range of products at varying densities, a conversion was necessary to reliably calculate how much product was required. In the past, as soon as the levels in the 600-gallon vat dropped below 100 gallons, the accuracy of the whole system was reduced, causing large discrepancies in the end product. However, this no longer happens with the upgrades.
“We have found that using load cells is far more accurate, sanitary, faster and altogether easier,” says Klein. “We hope to add load cells to additional vats in the future.”