For the past few years, Monsanto's Muscatine, Iowa, manufacturing facility has undergone a transformation in communication, in part through exploiting the capabilities of HART Communication in order to enhance reliability data and help the plant achieve a new level of productivity. The success Monsanto had incorporating instrument data into a comprehensive reliability strategy earned them the 2012 HART Plant of the Year Award.
The Muscatine facility spans 150 acres and employs more than 450 to operate and manage eight process units running 24/7, year round, to produce agricultural chemical products including Roundup herbicide and Acetanilide Select Chemistry products including Harness Xtra, Degree Xtra, and Warrant herbicides. Starting in 1997, the installation of HART Communication-compliant devices has helped enable the plant to switch from batch to continuous operation across processing units as well as in its waste treatment and utility process and formulations and packaging process.
Operating since 1961, the plant has undergone various changes and expansions, resulting in a variety of automation systems. Ongoing efforts have helped to integrate systems site-wide, including a SAP computerized maintenance management system (CMMS) and Emerson AMS Suite asset management system.
This is a distributed platform that includes a central server, which hosts a master database and interfaces with three DeltaV distributed control systems (DCSs) and four legacy Provox DCSs. Additional applications are also installed, including: ValveLink software to manage control valves, AlertTrack for pushing critical device alerts to plant personnel; AMS Wireless for interfacing with a WirelessHART network; and Connector software for pushing/pulling information between the database and the calibration database. These systems and applications manage control networks site-wide.
In turn, control networks connect to more than 600 HART-enabled devices with more than 3,200 instrument assets total.
Setting Asset Priorities
"Asset Prioritization is the foundation of all our reliability programs," says Joel Holmes, site reliability engineer. That prioritization consists of continual evaluation and ranking of equipment according to several criteria that, in turn, determine the level of criticality for individual plant assets.
Initial efforts to prioritize assets included the reliability team's 2006 discovery of a dramatic 30% error in its SAP CMMS system, which lacked the ability to track reliability work such as labor and material costs to the level of specific assets. In keeping with the plant's Lean Sigma initiative, the plant reduced that error to below 5% by instituting order codes and deficiency notifications. This translated into more than 5,000 SAP records corrected.
By 2008, the plant's use of predictive maintenance included various conditioned-based monitoring technologies. These include vibration, infrared thermography, motor analysis/testing, lubrication/greasing and ultrasonic analysis. These paid-off in one case with detection of the early signs of plugging in two mass flowmeters; back-flushing prevented up to six hours of downtime that valued at $100,000 per hour.
"By implementing conditioned-based monitoring techniques, we can effectively identify, diagnose, troubleshoot, and ultimately repair issues prior to their effects negatively impacting production," Holmes says.
Hooking-up with HART Technology
Since 2008, the plant has instituted a new level of reliability optimization to help prioritize, plan and schedule maintenance downtime for ongoing predictive maintenance, preventive maintenance and control valve maintenance programs. This began with the Asset Criticality reviews in which the reliability team assigned ratings to more than 14,000 pieces of equipment and instrumentation plant-wide, including transmitters, control valves, and vapor sensors. Each asset was evaluated and assigned an A, B or C ranking, most critical devices getting an "A" ranking, while others -- such as run-to-fail assets or those with inline spares -- being assigned a "C."
The installation of the asset management system made it possible for the plant to use smart I/O communication with digital fieldbuses as well as, for the first time, the digital portion of the HART protocol's signal. Today, the system encompasses approximately 700 HART-enabled devices and smart valve positioners.
There are two phases to the program, representing two levels of use of HART communication:
Phase I employs evaluations in the field using a handheld communicator or mobile computer to capture diagnostic data to an Excel-based file and, in turn, the CMMS, along with any deficiency notifications. This allows technicians to effectively identify, plan, schedule, kit the needed parts and execute maintenance tasks.