Advancing the Practice of Operating Asset Condition Monitoring, Diagnostics and Performance Optimization

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New Course: System 1 for Portables

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case study

This instructor-led course teaches students to use the System 1 for Portables software in a variety of practical daily use situations. The software consists of two workspaces: Configure and Diagnose. In the Configure workspace, you will set up your enterprise by building assets, entering their properties, and defining the instrumentation for collecting machine condition data. After completing your configuration, you will move to the Diagnose workspace, where you will interface with the Bently Nevada SCOUT series and the Commtest VB series portable data collection instruments and view machine information in formats such as plots, event logs, and machine diagrams

 

Course Objectives

Upon completion of the course, students will be able to:

  • Create an Asset Group, add a machine train and machine and it’s properties.
  • Use the Automated Instrumentation Process to add instrumentation.
  • Create a Route of measurements to be taken.
  • Use the Scout or VB instrument to collect data and then send to System 1.
  • Use the Status tab and Plots tab to analyze the collected data.
  • Configure 6 Pack and individual points.
  • Analyze Faults and Alarms.
  • Create Templates for assets and its measurements.
  • Manage access through the security manager.
  • Restoring and backing up a database.
  • Remote communications set up for Scout 200 and VB 200 data collectors as well as for a remote server.

Updated ADRE 408 and AMD Training Courses!

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condition_monitoring_adre_408

Favorites of machinery professionals around the world, GE’s Bently Nevada ADRE 408 and Advanced Machinery Dynamics (AMD) training courses have been updated with workshops, new case histories and material that benefit those new to the machinery diagnostics and APM (Asset Performance Management) field as well as having interest for refreshing and networking.

For more details on these courses and others check out GE’s Bently Nevada Training Website

 

ADRE 408 DSPi / Spx Rev 4

 

  • Two topics, Vibration Data Fundamentals and Signal Processing, have been added to ensure sufficient background and knowledge about vibration and signal processing
  • Numerous topics have been updated for clarity and additional details
    • Configuring a Database
    • Collecting Data
    • Plot Session Management
    • Advanced Features for Static Data Plotting
    • Dynamic Data Plotting
  • A Final workshop has been added for students to practice, as if they are on site in front of a 3500 rack with an ADRE 408.   Students will configure the ADRE database, collect data, and compare data between two runs
  • Other topics have been added for reference
    • replay card
    • power card
    • front panel, and more

Advanced Machinery Dynamics Course Rev 6

(The Advanced Machinery Dynamics course essentially begins where the Machinery Diagnostics course leaves off)

  • The course topic on Anisotropy has been removed and replaced with a new topic on Magnetic Bearing Design
  • The course topic on Signal Processing has been redesigned
  • A new topic on Gear Failures and Inspections has been added
  • Four new case histories have been added
    • Steam Turbine Rub Oil Coke
    • High Synch 1X in Generator
    • Oil Whirl Expander
    • Compressor Sudden High

GE’s Bently Nevada Product Line Engagement

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Solution Specialists_Q116_1

Bently Nevada has always believed that the key to strong and long-term relationships with our customers is a function of the quality of our sales and services teams in the regions we operate in.

Strong local support demonstrates to our customers our commitment to them and on the sales side of things that means account managers who fully understand the Bently Nevada technology and can explain that functionality.

Since GE’s acquisition of Bently Nevada in 2002, our business has effectively tripled in size and our technology portfolio has expanded dramatically, so much so that it is now practically impossible for a local account manager to fully understand and explain it all!

Bently Nevada has responded to that challenge in a very effective manner by establishing an innovative two-tiered approach.

Solution Specialists

The first stage of that approach is a four-level Solution Specialist training program, with all Bently Nevada account managers progressing through a specially developed series of modules designed to teach them what our technologies are, what they do and how they all work together to deliver value to our customers.

Levels one, two and three of the program are conducted in-region, while Level four is an intensive two-week session conducted at the Bently Nevada headquarters in Minden, Nevada, USA.

The Solution Specialist training program is a major, but essential, investment in the capability of the global Bently Nevada sales team.

Field Application Engineers

The second stage is our investment in Field Application Engineers – FAEs, who are the local technical support to our Solution Specialists.

FAEs are trained on how the Bently Nevada technology does what it does, as well as how to best use our technology at a customer’s site.

They are equipped with the latest hardware and software demonstration capability and are able to show customers how our technology operates and provides critical data.

To keep all FAEs current with what we are doing to support, sustain and enhance all of our technologies, every year we conduct a two-week learning session at our US headquarters in Nevada.

All of the global FAEs travel in to Minden for that session, where they are given detailed briefings by the people who design and build our technologies so that when they return to their regions they are fully competent to support our Solution Specialists and their customers.

 

Don Silcock

Technical Sales Director

don.silcock@ge.com

Hydro Corner: Third Quarter 2015

in Departments/Featured/Features by
ADAPT Hydro 2

In this issue:

  • Product Feature:
    New ADAPT Hydro Monitor
  • Technical Topic:
    Unit unbalance problems

New Monitoring System for Hydro Generating Units


GE introduces the Bently Nevada* ADAPT 3701/46 Hydro Monitor, the latest in a family of compact, high performance safety and machinery protection and condition monitoring solutions.  ADAPT (Advanced Distributed Architecture Platform Technology) products excel at the intensive signal processing needed to identify machine-specific malfunctions and precursors to failure.  The 3701/46 Hydro Monitor is ideal for small and medium-sized hydro turbines where a compact and powerful ADAPT Hydrodistributed monitoring or protection system is appropriate.

What it is

ADAPT Hydro consists of a 3701/46 Hydro Monitor module, one or two 6-channel input modules, and a relay output module.  The six channels of each input module can be independently configured for Acceleration, Velocity, Radial Vibration, Thrust Position, Dynamic Pressure, Speed, and Keyphasor*, and there is also a seventh dedicated Keyphasor channel. Each measurement type has a default configuration, including a Rough Load Zone measurement for guide bearing vibration, and a Cavitation measurement for draft tube accelerometers.  Vector (1X, nX, etc.), band-pass filtered, and peak detection measurements can be added to a channel to detect vibration characteristics associated with specific malfunctions tuned to your specific machine.

What it does

Features:

  • Compact form factor for installation at the machine.
  • Accepts a wide array of vibration, speed, and pressure sensors.
  • Eight (8) configurable SPDT alarm and protection relays.
  • Raw transducer signal buffered output connectors.
  • Two independently addressable Ethernet RJ45 connections.
  • Modbus TCP protocol allows levels and alarms to be viewed via industry-standard displays.
  • Synchronous and asynchronous waveforms can be viewed real-time using the optional System 1* Basic display software.
  • Configured and validated with Bently Nevada Monitor Configuration (BNMC) software.

Benefits:

  • State of the art electronics and signal processing helps you focus on key machinery health indicators unique to your particular machine.
  • Cost-effective solution enables you to expand reliable protection and remote monitoring to more of your hydroturbine generating units.
  • New generation platform ensures robust, long term lifecycle support.

Where it’s used

The 3701/46 ADAPT Hydro Monitor is ideally suited for small and medium-sized ADAPT Hydro 2Francis, Pelton, and Kaplan turbines where high channel count and generator air gap are not required, and where bearing and other temperatures can be taken directly into the control system.  ADAPT Hydro easily connects to SCADA and unit controls so that specific machine conditions and problems can be remotely detected and managed.  The combination of ADAPT Hydro and 3701/55 ADAPT ESD can serve as a complete small unit protection system.

Ditch the vibration switch, and let ADAPT Hydro help you make intelligent machine decisions!

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Technical Topic


In each issue, we cover a machine malfunction or other technical topic relevant to hydro turbine generator units.  In this issue we’ll cover unbalance and shaft bow.  As we’ll see, although the root causes are different, the forces and resulting vibration characteristics are very similar.

Mechanical Unbalance

Mechanical unbalance is a non-uniform mass distribution about the shaft geometric axis and results in a periodic excitation force at rotational speed. This force produces a synchronous (one times running speed, or 1X) vibration. For machines that rotate at low speeds well below their first balance resonance (critical speed) the vibration amplitude increases approximately as the square of the machine speed. The vibration phase angle may remain fairly constant, or it may increase somewhat (in the lagging direction), depending on the specific characteristics of the machine.Hydro COrner

Some possible sources of unbalance are mechanical damage to the turbine runner, a bowed shaft, or distortion of the generator rotor due to loose banding or thermal effects. In the case of thermal effects, the vibration amplitude may not increase as the square of the speed initially, but may be dependent on generator loading which causes thermal distortion of the rotor.

If the mechanical unbalance is due to a combination of causes, the effects will depend on which effect is dominant. Any changes to the synchronous vibration amplitude or phase, whether increasing or decreasing, may indicate a mechanical balance problem.

Shaft Bow

Shaft bows in hydroelectric machines can be caused by the thermal effects of mechanical friction between rotating and stationary parts (i.e., bearings), or asymmetric heating in the generator rotor.  Any bow in the shaft system will produce synchronous shaft motion. Shaft bow will introduce a 1X vibration or run out in exactly the same way as a mechanical unbalance.

If the bow is present at the start of the run, the machine will behave exactly as if an unbalance were present. The vibration amplitude will increase as the square of the machine speed at a phase lag angle that is constant, or that is increasing slightly. If the bow is due to a shaft rub or other non-uniform heating effect, the vibration amplitude and phase will quite likely change over time.Hydro COrner 2

If the machine is tripped with a thermally-distorted rotor, the vibration amplitude will reduce as the square of the speed at a constant phase angle during the coast down.   This is because the rotor will not have time to cool significantly during the relatively short time that it takes for the machine to slow down and stop turning. When the machine is allowed to cool before restarting, it will behave in a normal way with the vibration increasing again with time as the thermal effects become dominant.

Magnetic Unbalance

Magnetic unbalance occurs when the magnetic field forces between the rotor and the stator are not uniformly distributed around the entire rotor. This will occur if an individual pole has a larger or smaller air gap than its neighbors, or if it has a smaller than normal magnetic field, due to shorted windings.

When an individual pole has a weaker than normal magnetic field, a unidirectional resultant force will be exerted on the rotor, in a direction that is 180 degrees away from the affected pole. If you can determine the direction of the magnetic unbalance vector (using the phase lag measurement), it may be possible to narrow down your diagnosis to the approximate area on the rotor where the shorted windings are located.Hydro Corner 3

In order to observe purely mechanical unbalance separately from the combined mechanical and electrical unbalance, you will need to take measurements with the rotor at speed, but with the field de-energized. Depending on the size and orientation of the magnetic unbalance force, vibration amplitude and phase could either increase or decrease when the excitation breaker is closed. The important point is that a change occurs at the exact time when excitation is applied to the field. If magnetic unbalance exists on a running generator, a corresponding vibration change may be observed at the moment that the excitation breaker is opened during unit shutdown.

Conclusion

As we’ve learned, unbalance and rotor bow show up as high and/or changing 1X vibration, with or without changes in phase angle.  To detect these malfunctions, a proper monitoring system should have guide bearing proximity probes and a Hydro Corner 4Keyphasor* transducer.  The monitoring system should have the ability to calculate and display the 1X vibration vector (amplitude and phase angle), and output these values to a SCADA system for trending.  An additional tool that can help you distinguish between mechanical and electrical unbalance and rotor bow is diagnostic software.  Systems like Bently Nevada System 1* or ADRE can display the 1X amplitude and phase data in useful formats such as bode, polar, and waterfall graphical plots.


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Links to More Information

 

ADAPT Product Family Webpage

ADAPT Microsite

Interactive Web Demo (click on “Product Animations” in the upper-left, and select the 3701/46M from the drop-down menu)

Download 3701/46 Data Sheet

Download 3701/46 Fact Sheet

System 1 Basic Product Webpage

System 1* Product Webpage

ADRE Product Webpage

 

To subscribe, or for more information on the contents, please contact your GE Bently NevadaTM product line representative or the author:

Mark Snyder, P.E.
Sr. Field Application Engineer
Email: mark.snyder@ge.com

© 2015 General Electric Company.
All rights reserved.

* Indicates a trademark of the General Electric Company.

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