Desktop Diagnostics Streamline Valve Maintenance at Wayagamack

Pulp & Paper, Mar 2005 by Lagac�, Jean-Guy, Williamson, Mark

After helping Kruger achieve a fast No. 4 paper machine startup, an online valve and field transmitter diagnostic system proves its worth as a predictive maintenance tool

Process measurements and controls are now an essential part of the success of any paper process startup. If the initial wiring is not absolutely correct or if control devices malfunction at startup, the process may suffer through many days of instabilities and shutdowns required to correct the problems.

Therefore, the time and effort spent in checking a multitude of field transmitters and valves before the water runs and up to the startup date are critical. In the past, that essential task required many hours of painstaking, repetitive checking by technicians working in two places: in the rack room and in the field, right next to the transmitters.

Today, with modern smart valves and transmitters and remote diagnostics by desktop systems, the labor intensity can be reduced significantly, the costs can be minimized, and the malfunctions at startup can be avoided. This streamlined device checking makes for an effective startup.

Flawless Startup Signals Promising Future

The Nov. 1, 2003, startup of Kruger Wayagamack's new No. 4 online lightweight coated paper machine was the type of startup that papermakers dream about and, "one of the best startups in Kruger's history," according to Daniel Archambault, general manager. The project was on an accelerated schedule, with the startup taking place only 22 1/2 months from the date of order, compared to the original plan of 26 months.

The Metso Automation FieldCare remote configuration and diagnostic system for valves and field transmitters was an important ingredient in ensuring the flawless startup of the No. 4 paper machine line. This asset management system allows remote configuration and performance diagnostics of Neles valves with smart ND800 positioners (also supplied by Metso Automation) and numerous process measurement devices. It has saved time and money for field device calibration and checking the connections. Altogether, there are 817 connected devices at Wayagamack, about 98% of the total number of field transmitters and valves. Machine and process controls are accomplished through a metsoDNA system.

After the startup, the FieldCare system has been used effectively as a predictive maintenance tool, alerting E&I maintenance personnel to potential problems before they became failures, as well as allowing effective maintenance planning and solving process stability problems.

Standards Ensure Full Access, Consistent Interface

The ability to remotely access, configure, and diagnose the performance of devices from a variety of suppliers relies on the FDT/DTM technology. FDT stands for field device tool, an open industry specification that standardizes the communication interface to valves and field devices, regardless of the supplier. Currently, 35 instrumentation and process automation suppliers support this specification. It is similar in concept to the "plug and play" facility that enables PC users to easily connect various peripheral devices.

FDT enables the integration of communications to various DTMs (device type managers), which are device-specific software applications offered by the individual suppliers. These DTMs enable remote configuration, calibration, and diagnostics tools through a PC-based user interface like FieldCare. These DTMs can be compared to printer drivers in a Windows environment.

Currently, FDT allows FieldCare to access any DTM device through Profibus, Foundation Fieldbus, or HART Gateway. Metso Automation says more protocol accesses are on the way. On Kruger's No. 4 paper machine project, this interface is through the FlART Gateway protocol. The metsoDNA control system was specified with integral HART interface cards to the valves and field transmitters specified in the scope of the project. The FieldCare system is directly connected to these DCS interface cards. As a result, the E&I maintenance people have desktop access to the valves and field transmitters with a consistent user interface for diagnostics, alarm handling, and reporting.

No Crossed Wires at Wayagamack

For the No. 4 paper machine startup, the FieldCare system was justified as a cost-effective commissioning and problem troubleshooting tool. Before the pre-startup "water runs," the operation of all process measurements and valves had to be perfect; crossed wires had to be eliminated beforehand. But that could have taken a lot of time, with high labor costs. With the remote links, the integrity of the wiring was easily verified, and a lot of time and labor was saved in commissioning and calibration.

The software remotely identifies any loose connections or improper installations without taking off the instrument or valve cover. This avoids tedious checking of wiring by two people at either end of the cable, communicating by radio. All tag names for each device are factory assigned. This is a direct economy because it avoids field calibration. Once installed, the factory tags and configuration settings are verified. Replacing a device is easy because the factory settings can be downloaded directly.