During the past three years, production capacity at Ash Grove, Cement's Durkee, Ore. plant has doubled from 1,500 tons per day of Portland cement to about 3,100 tons per day. Part of that increase can be attributed to new equipment; the rest is tied to fine-tuning the production process and enhancing equipment maintenance. Today, the Durkee plant may be the company's most efficient U.S. plant, thanks to a computerized maintenance management system (CMMS) that allows it to operate 24 hours a day, seven days a week, 50 weeks a year, with only one planned two-week preventive maintenance (PM) shutdown.
Targeting maintenance
The Avantis.PRO system from Invensys Software Systems was selected as a key component of a company-wide maintenance initiative called the Maintenance Excellence Process (MEP). Initially, the system was used as a "get it into the system so we don't lose the data" kind of solution, said Bernard Sherin, maintenance manager at the Durkee plant. "We were successful there, but we didn't take advantage of some of the planning or sorting functions." That has changed as more of the Avantis features are used. "We've found that being able to manage the backlog through Avantis has been really easy, and we have a much better handle on our workload since we started using some of those other features, such as criticality, value lists and priority value lists," Sherin explained.
The Avantis system uses the "entity" concept to facilitate recording of costing and maintenance activity records. Work management features ensure maintenance personnel have control of incoming work, while planning functions include information on labor, materials, tools, drawings and instructions and subcontractor requirements. Preventive maintenance functions can be structured in libraries of standard jobs with automatic work order generation, inspection checklists and PM routine specifications. Avantis.PRO builds a detailed history of equipment information based on day-to-day maintenance activities, letting supervisors analyze failure histories, track failure causes and take appropriate actions.
Maintenance was critical, not only to maintaining a 24/7 schedule, but also in the redeployment of equipment as the plant was upgraded to increase production. Durkee's maintenance group spends close to $3 million a year on maintenance and includes 18 mechanical specialists. Under the company's MEP, the Durkee staff has committed to daily scheduling, followed by a period of weekly scheduling and, eventually, three-week scheduling of PM. By then, the staff expects 85 percent of its work to be preventive.
Meeting environmental goals
Something else Ash Grove doesn't want is to violate its environmental compliance requirements. In 2000, that compliance became more challenging with the passage of a new regulation by the U.S. Environmental Protection Agency (EPA) that requires Portland cement producers to use maximum achievable control technology (MACT) to control air emissions.
Ash Grove uses Avantis.PRO as the data collector for supporting its environmental compliance program. "One of the critical issues in the PC MACT program is to have PM set up and documented, including standard operating procedures that demonstrate to regulators that we've followed these procedures," explained Sherin. "We know we'll be depending on Avantis to maintain our history of all operations to meet the new regulatory requirements."
