by Dennis Shreve, Commtest

Pumps & Systems, September 2007

Economic pressures to minimize production downtime and improve operating efficiency are increasing the emphasis to accomplish on-site problem detection, analysis, and resolution as fast as possible. These requirements place a great deal of pressure on maintenance personnel to have all the right tools readily available in one place.

Competitive Sunset: An Evolution

Over the last several decades, our industry has experienced an evolution of portable instruments: from those that read the data (detection), to sophisticated host-based software that determines root-cause (analysis), to yet more equipment that offers the problem solution (correction).

The level of sophistication in modern handheld electronic devices, coupled with the experiences and success of new technology in predictive maintenance, now allow all three functions (detection, analysis, and correction) to be integrated into a single, compact, easy-to-use package.

Two major drivers affect the development activities of portable instruments and systems - available technology and user requirements. A tradeoff lies between what can be provided in a new product on the technology front relative to what users really need and can afford to pay.

Although the following list is by no means comprehensive, it represents a typical set of requirements from a predictive maintenance (PdM) user's viewpoint:

  • Small, lightweight, and handheld package.
  • Proven platform for performance.
  • Accurate and reliable.
  • Functionally independent, with no major dependence on host software.
  • Easy to use and intuitive operator interface.
  • Complete package, with all accessories and peripherals included.
  • On-board data storage and recall.
  • Built-in analysis capabilities for vibration amplitude, frequencies, and phase.
  • Two-plane balancing capability.

Note that these qualities span all three fundamental elements of asset management: detection, analysis, and correction. This means new portable vibration analysis technology must somehow move beyond the evolution in portable instrument design and incorporate the latest advances in electronics that address all three of these elements - at the same time.

Competitive Sunrise: A Revolution

In other words, to continue providing users with a competitive advantage under increasingly tough economic pressures, a revolution must take place in portable vibration analysis technology.

That revolution has started.

Though practical economics is always a major limiting factor in providing new instruments to market, the newest portable technology meets at least 95 percent of the identified needs above at a relatively low cost. Furthermore, in utilizing the latest technology available, new vibration analyzers are fully capable of including additional features and functions enhancements for years to come.

For example, one fundamental consideration for new vibration analyzers is to provide data collection, analysis, and correction (2-plane balancing) in one easy-to-use, intuitive package. This type of system allows users to get an active program underway with little or no training, yet be powerful enough to satisfy the needs of the most advanced analyst.

The newest portable technology meets user demands for vibration analyzers to be small and lightweight, yet with rugged packaging for portability. Handheld technology is now small enough for analyzers to be as compact as 10-in x 5.5-in x 2.25-in, with a weight of 2.5-lbs.

Some new portable instruments have breakaway straps and cables for safety. Neck strapping included with a vibration analyzer also allows for ease of carrying on route and using in data collection, analysis, and correction modes of operation. Coupled with the structured and predefined route for prompting the order of collecting data, the ability to skip machines, points and measurements is essential. New technology includes the ability to add off-route data to a predefined database.

New designs come with an ergonomic soft-key layout that duplicates dedicated function keys on the left and right sides to create versatility and flexibility for the user.

The newest technology includes a long life, lightweight lithium ion (Li-ion) battery that provides 8 to 10 hours of use on a full charge, enough power for full-shift applications. This enables the instrument to carry a high-speed processor for fast data acquisition and have a large memory capacity for flexibility in database formatting and data storage.

At initial power on, new vibration analyzers allow the user to quickly gather meaningful vibration data on time waveform, frequency, and rolling-element bearing condition via factory default settings and a prompting menu structure. That's not all. Advanced analysis capabilities, including cross-channel phase, coastdown, bump test, time synchronous averaging, and long-time waveform capture are readily available on the measurements menu screen.

Users have indicated the need for better graphical representation of data, including polar vector plots for amplitude and phase information, in an easy-to-understand format. In response, certain portable units now provide a large landscape-oriented, back-lighted HVGA gray scale LCD screen for high resolution presentation and good readability of data for clear graphics display and analysis.

Along with the inclusion of dual processors for speed of data collection and presentation, high resolution hardware is incorporated into the newest portable vibration analyzers to discern even the smallest vibration signal in the presence of noise.