Tag Archive for: vibration

Machine Failures Caused by Intermittent Damaging Events

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Over the years we have been tasked with identifying the root cause of machine structural failures. In many cases, we can determine the failure mode through strain and vibration testing, order analysis, modal analysis, and operating deflection shape analysis.  What tests can you run when the damaging conditions are intermittent and not easily identified?

In these cases, we like to install a cellular networked temporary data acquisition (DAQ) system that can autonomously log vibration and strain data along with machine status data. We have deployed two types of DAQ systems to collect data remotely.  An interactive system that includes an industrial PC running our iTestSystem software and National Instruments (NI) Compact DAQ hardware and a headless system that utilizes NI Compact RIO hardware.  Our test engineers prefer using the interactive solution for troubleshooting because they can view real-time signal waveforms and collected data files, and then adjust the test parameters accordingly without having to reprogram the hardware.

Rugged Measurement System

Figure 1: Headless networked data acquisition system

When potentially damaging events are identified in the vibration and strain data collected by these systems, it is important to know the machine’s operating status. Collecting the machine status information is just as important as collecting the structural data.  Many machines transmit these operating variables and operating stages over their network/bus.  Recently we have recorded process data from Allen Bradley Control Logix PLCs via Ethernet/IP, mining machine data from a Siemens controller via proprietary TCP/IP protocol, boiler condition data from a DCS via Modbus TCP,  machine pressures from PI historian via the UFL connector (TCP), and vehicle speeds and pressure via CAN.  Fortunately, we were able to use and adapt LabVIEW communication protocol tools to build applications and addons that allow this network tag data to be collected along with structural data.

LabVIEW Modbus to Shared Variable Code

Figure 2: Modbus to Shared Variable Tool

After the data collection phase, our engineers perform statistical analysis on the sensor and status channels in all data files and aggregate the results into a database for searchability. To identify the root cause probabilities, you can process the channel statistics data using your favorite correlation algorithm or application.  The image below shows an example data set containing related sensor data that was processed using a LabVIEW correlation test tool.

LabVIEW Correlation VI

Figure 3: Correlation Test Example vi

Contact Information: For more information about our remote data acquisition service, our LabVIEW development service, or iTestSystem contact:

Mark Yeager – Integrated Test & Measurement (ITM), LLC.  Email: mark.yeager@itestsystem.com or Phone: 1.844.TestSys

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FieldDAQ Sound & Vibration Module compatibility added to iTestSystem

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The FieldDAQ™ FD-11634 sound and vibration input module from National Instruments (NI) can now be used with the latest version of iTestSystem for your data collection needs.  The FD-11634 is similar to the NI-9234, NI-9232, NI-9231, and NI-9230 cDAQ dynamic input modules and can be used with IEPE type sensors such as accelerometers and microphones.  Like the other FieldDAQ™ modules, this module is IP65/IP67 dust and water resistant with an operating temperature range of  -40 °C to 85 °C.  Our test engineers would use these modules for collecting vibration data on mining and construction equipment, vibration data on rotating machinery within manufacturing facilities and test cells, and acoustic data for measuring equipment noise emissions.  No matter your need, data logging with this equipment is sure to impress.

The FieldDAQ™ FD-11634 module has 8 simultaneous sampled, ±1V or ±10 V, 24-bit differential input channels with AC/DC coupling. It has a maximum sample rate of 102.4kS/s and features built in anti-aliasing filters that automatically adjust to the sampling rate.

For advice about using the FieldDAQ™ FD-11634 sound and vibration modules in iTestSystem monitoring applications or with custom cRIO RT and FPGA control applications contact Mark Yeager or Chase Petzinger.

Click Here to view a video showing one of our test engineer collecting data from a submerged FieldDAQ™ module with iTestSystem.

Click Here for more information about iTestSystem.

iTestSystem Update: Joint Time Frequency Analysis Tool

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Over the past few weeks we have been updating our Joint Time Frequency Analysis (JTFA) tool for iTestSystem. In general, the JTFA tool is used to show how the frequency content of a signal changes over time. This tool is particularly useful for analyzing and visualizing vibration and strain data on rotating machinery.

After using the JTFA tool on an internal data analysis project with a colleague, we realized that with a few additions and changes, the tool’s capabilities and processing efficiency could be greatly improved. To achieve this, we added a configurable overall frequency band algorithm for trending frequency bands related to specific machine fault or vibration modes. We also added templates for quickly developing and switching between frequency band signatures and settings. Finally, we added the capability to export the results to a data file for later viewing in TestView Plus or Excel.

These changes are included in the latest version of the JTFA tool. For a free trial of iTestSystem and the JTFA tool, contact chase.petzinger@itestsystem.com.

Mark Yeager – Cat III Vibration Analyst Certification

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Congratulations to Mark Yeager for obtaining Category III Vibration Analyst Certification.

Category III Vibration Analysts are qualified to establish, direct, and\or perform programs for condition monitoring and diagnostics of machines including spectral, waveform, and orbit analysis. Category III certified Vibration Analysts are qualified to perform minor corrective actions involving operating deflection shapes, single-plane balancing, and diagnostic testing.

For information about our Vibration Testing Services, contact Ryan Welker at (844) 837-8797 x702.

Ryan Matthews – Cat III Vibration Analyst Certification

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Congratulations to Ryan Matthews for obtaining Category III Vibration Analyst Certification.

Category III Vibration Analysts are qualified to establish, direct, and\or perform programs for condition monitoring and diagnostics of machines including spectral, waveform, and orbit analysis. Category III certified Vibration Analysts are qualified to perform minor corrective actions involving operating deflection shapes, single-plane balancing, and diagnostic testing.