Preventing Downtime in a Harsh Salty Environment
Salt can be very destructive, constantly eating away at metal surfaces. After seeing firsthand how salt can damage weighing equipment, a solar salt producer in New Mexico turned to METTLER TOLEDO for a truck scale that would stand up to the harsh environment at its plant.
The New Mexico plant produces solar salt from a 2,600-acre salt lake. Solar salt is evaporated naturally by the sun and wind and then harvested from the surface of the lake. After carefully washing the salt, the plant packages it as 50-lb blocks, compacted pellets, and other products.
Much of the salt is used for water conditioning in advanced water purification and processing. Other solar salt applications are agricultural feed products, chemical feed stocks, chlorine for swimming pools, and deicing salt for roads.
Weighing is an essential part of operations throughout the plant. The quality-control laboratory uses balances when testing pro-ducts, and the packaging operation uses scales for filling bags by weight. At the end of the production line, a truck scale weighs 50 or more truckloads of finished products per day.
Over the course of a year, the plant ships roughly 400,000 tons of salt. If the truck scale is out of service, shipping stops. In fact, the truck scale is so critical to the plant’s operation that the company is considering buying a second scale to serve as a backup and allow for future growth.
The plant’s previous truck scale came from Fairbanks Scales. Although the scale was only 15 years old, corrosion had ended its useful service life. Salt constantly collected in the scale’s pit, damaging the load cells and the scale’s understructure. According to the plant’s maintenance superintendent, “The old system had too many exposed moving parts that broke down in our environment.”
The maintenance problems forced the company to replace the scale in 2010. After evaluating bids from several suppliers, the company purchased a new METTLER TOLEDO scale from Rusty’s Weigh. This authorized METTLER TOLEDO distributor had provided excellent service to the salt plant for many years. The new truck scale is installed above ground rather than in a pit, simplifying cleaning under the scale. To ensure that the scale remains in good condition, the company purchased a quarterly service agreement.
The new VTC221 concrete deck truck scale is equipped with an IND780 terminal and POWERCELL® PDX® load cells made of corrosion-resistant, 17-4 precipitation hardened stainless steel. Its advanced CAN bus network eliminates junction boxes, which are a primary cause of truck scale failure. Instead, each load cell is connected directly to the next one in the network by cables with protective stainless steel sheathing.
A unique predictive diagnostics system monitors load cell performance, alerting the scale operator about potential problems. If a load cell canister were to be punctured during cleaning, the scale terminal would warn the operator about the damage. This proactive alarm system allows the company to plan for service before the scale experiences weighing errors or downtime. When combined with preventive maintenance, the POWERCELL PDX predictive diagnostics system can eliminate costly unplanned downtime.
Quality products from METTLER TOLEDO and excellent service from Rusty’s Weigh ensure that this solar salt plant will keep shipping its products on time.