KCF Technologies Blog

Predictive Maintenance is Vital in Fixing America's Aging Water Infrastructure

Gregory M. Baird, Managing Director and Chief Financial Officer of AWI Consulting LLC, alsohas served as the CFO of Colorado's third-largest utility, and finance officer of California's 17th-largest city.  He has thus had a sharp eye on the emerging crisis of America's crumbling water and wastewater infrastructure--both from the perspective of revenue-strapped public utilities in a water-challenged West, and as an advocate of the best ways to meet the challenge.

Baird summarized much of his thinking in "The Aging Water Infrastructure," from which his consultancy's acronym was derived. It appeared in the November/December 2010 newsletter of Water Utility Infrastructure Management, available free in the US and Canada.  Those who prefer a graphic-rich presentation online can read Baird's 26-page pdf "The Aging Water Infrastructure (AWI): Needs and Challenges," prepared in October 2010 for the Rocky Mountain Chapter of the North American Society for Trenchless Technology (RMNASTT).

It is hard to overstate the extent of the challenges faced by the systems that carry and cope wit US water and wastewater, vital and related utilities we rely on everyday.  "Community water systems include over 1.8 million miles of network pipes," Baird notes, along with the breathtaking estimate that there are 21 feet of sewer pipe for each of 314 million Americans.

More disturbingly, much of the vast network of buried pipes and pumps that serve our largest cities were installed when most transportation was by horse and electrification was an emerging technology.  Any changes or improvement will be massive undertakings.  Furthermore, the gap between what it will take to repair and update this critical infrastructure and the money actually set aside for that work grows each year.

What Baird champions is an asset-management strategy that is both affordable and sustainable, in which work is allocated to extend the life of water and wastewater assets in the most cost-effective manner possible.  "There is no one-time fix," as he pointedly reminds us.  "This momentous task of addressing the aging infrastructure dilemma requires overcoming many challenges, especially during this extended economic crisis."

One of the keys to doing so, Baird says, must be predictive maintenance.

"As city councils are educated on asset-centric business practices, they begin to comprehend that the water and wastewater utilities are the most capital intensive industries," he observes.  "...in order to attain cost savings, operational efficiencies and lower future risks a return to properly maintaining our assets and extending an asset's useful life in a cost-effective manner is required."

"About 90 percent of US water and wastewater utilities use a geographic information system (GIS).  Every utility is actually on an asset-centric path using GIS for mapping, ...next expanding with additional GIS applications and finally achieving an enterprise-wide operation.  When the investment in GIS is the focus and the whole enterprise is the vision, the full power of GIS tools and functionality can be employed for long-term cost savings."

"An asset registry (geo-database) combined with a [computer maintenance management system] (CMMS) creates a foundation for an enterprise asset management system (EAMS) as promoted by the EPA.  This simple and powerful combination captures asset data, work history, and condition assessments necessary to produce cost-effective, condition-based and predictive maintenance programs."

"This era of sustainability, deliberation, and economic downturn is not for the weak of heart," Baird concludes."  [Water and wastewater] rates will need to increase, and if affordability is truly a core concern then there must be a change from the crisis management approach of waiting for the next sink hole and fixing it to a predictive methodology to avoid even higher rate increases."

Non-Intrusive Electric Load Monitoring Still Promises Tantalizing Diagnostic Potential

Dr. Michael R. Brambley has more than 30 years of academic and research experience related to energy.  He has spent the last 22 years at the U.S. Department of Energy's Pacific Northwest National Laboratory (PNNL) focused on improving energy efficiency in buildings.  At PNNL, Dr. Brambley has served in a wide variety of roles including principal investigator, project and program manager, technical group leader, department chief scientist, and research contributor.  Most of his work over the past 15 years has focused on improving the operating efficiency of buildings and other energy systems, including air conditioning.

In September 2009, PNNL published a short study by Dr. Brambley with a long title: "A Novel, Low-Cost, Reduced-Sensor Approach for Providing Smart Remote Monitoring and Diagnostics for Packaged Air Conditioners and Heat Pumps."  It begins by noting a basic conundrum: "Operation Faults are common in packaged heating, ventilation, and air conditioning (HVAC) equipment...commonly used for space conditioning space conditioning of commercial buildings with less than about 50,000 square feet and many larger buildings with three floors or less....Remote diagnostic monitoring systems have been developed, bu they are expensive and, as a result, have not achieved significant penetration into the market.  Both hardware and installation costs are too high."

Noting that, "Smart monitoring and diagnostic systems (SDMSs) built for field testing...ina a follow-on to the current project had an estimated cost of approximately &1,000 per SDMS unit," plus, "an installation cost of another $200 to $1,000," Brambley conludes, "a much more lower-cost monitoring and diagnostic system is required to serve this market effectively."

His proposed solution?  "Basic non-intrusive electric load monitoring (NIELM) techniques can be used to extract information about the electricity use and efficiency of individual components of the heating, ventilation, and air conditioning unit from measurement of power supplied to an individual HVAC unit.  By using very few sensors, the capital cost and time/cost required for installation will be minimized, creating a monitoring and diagnostic system with a cost an order of magnitude lower than previous systems developed by the research team..."

Brambley details the original idea as developed by George Hart at MIT in the 1980s, and its evolution into various diagnostics systems.  "We hypothesize that much smaller sampling periods of tens of seconds to a couple minutes might be used to distinguish the on-off events of packaged unit compressors and fans to quantify...electric energy consumption."  He contends, "This together with measurements of outdoor-air temperature (and possibly return-air or supply-air temperature) should be sufficient to detect," six different faults on larger packaged air conditioning or heat pump systems.

What could make a NIELM system powerful and affordable is that it takes these limited power samples from the air conditioner or heat pump only when starting.  Key steps needed to convert the concept into workable technology are, "Adaptation of algorithms from previous work and development of some new algorithms for using NIELM to extract on-off times, power draw, energy use, cycling frequency of packaged unit compressors, and fans from the power connection to the unit ans implementation of them in software," followed by, "Development of a very low-cost hardware package with the necessary processing, data storage and communication capabilities for implementing the NIELM and fault detection algorithms."

In conclusion, Brambley opines, "The changes possible from successfully developing and implementing the NIELM-based technology...will help transform how packaged HVAC equipment is operated and maintained, increasing its operating efficiency and decreasing the energy used for space conditioning the 90 percent of commercial buildings and the 55 percent of commercial floor area that these units serve."  The savings could be still greater, he notes, if the technology were built right into the packaged units.

The promise that Dr. Brambley notes in this intriguing study is real enough, but so too are the barriers that have yet to be overcome to make NIELM-based technology a diagnostic game-changer.  Perhaps someday they will fulfill that great promise.

'The Advantages Are Clear:' Wireless Vibration Monitoring Answers a $65,000 Question

You could scarcely ask for a more upbeat title than "Wireless Vibration Monitoring - Improves Reliability and Enhances Safety," written by Travis Culham.  Culham is the Rotating Machinery Engineer at the Barking Power Station in the large, eastern suburb of Dagenham in London, England.  His article was published three months ago in maintenance.co.uk, "a monthly E-zine, featuring a mix of news and editorial articles" produced in the United Kingdom by Conference Communications.

"Taking advantage of the ease [with] which new measurement devices can be introduced to an existing Smart Wireless network," writes Culham, "our Barking Power Station is using a wireless vibration transmitter to monitor rotating equipment remotely and in real time.  The introduction of this device is helping to improve maintenance schedules and prevent unexpected downtime..."

"Monitoring techniques for rotating machinery have improved greatly in recent years," Culham notes, "with advanced vibration monitoring and analysis tools now able to identify even the slightest changes in the condition of an asset--as they are taking place.  Online vibration monitoring can help to predict when a failure will occur and alert maintenance as to the health status of the equipment.  Early warning of impending failures can prevent process shutdowns that lead to lost production."

"Continuous monitoring is making an important contribution....At Barking Power many of the largest and most critical pieces of rotating equipment have vibration monitoring permanently installed: ideally, all rotating equipment should be monitored..."

But just how important can such a high level of proactive predictive maintenance be?  Culham gives the seemingly trivial example of a gas turbine starter motor, housed in a hard-to-access compartment, from which, Manual readings were taken using a handheld collector and then downloaded for analysis."  This enhanced level of maintenance scrutiny was, important as these motors have a history of problems that can lead to total failure requiring replacement of the entire motor."

"Despite the potential problem, we wanted to continue to run the the motor; otherwise this affected our ability to run the related turbine, reducing our maximum output capacity by 200MW.  Shutting the motor down...and completing a total overhaul would make the turbine unavailable for approximately 36 hours.  Potentially this could cost our company as much as £50,000 in lost revenue (about $65,000), depending on the price and demand for power that day."

A wireless vibration monitor proved to be just the ticket.  "This success gave us great confidence," Culham recalls.  "If smart wireless technology could be applied here, then it could be applied pretty much anywhere throughout the plant."

In addition to its accuracy, remote vibration monitoring had other advantages: "Without the wireless vibration transmitter, we would have been unable to monitor the starter motor safely and would have had to take it out of service--with all the negative production impact that would have entailed.  Additionally, removing the need for maintenance personnel to visit the plant floor reduced risk."

"At Barking Power we want to continue to use technology to avoid forced outages...," he concludes.  "The advantages are clear.  We no longer need to have plant personnel make as many trips to the field, so safety improves.  We receive vibration data transmitted from the motor....This enables us to estimate when a motor is going to fail.  The real-time information from the wireless vibration transmitter provides valuable insight that can prevent unplanned shutdowns and improve maintenance scheduling and reliability."

SmartDiagnostics® Feature Highlight: Dynamic Alert Icons

Last month, our SmartDiagnostics® Feature Highlight briefly explained how to set a base line after a sensor node is placed on a properly working machine.  Page 35 of the SmartDiagnostics® Vibration Monitoring System User's Guide introduces the important subject of alarms and warnings (Section 5.4).  One of the principal values of the SmartDiagnostics® Vibration Monitoring System (VMS) is that it facilitates exception-based monitoring of machine condition.

If you are implementing a facility-wide condition-based maintenance program, you may have a large number of machines to monitor on a regular basis.  When you configure and apply monitoring bands with warning and alarm thresholds, you can let the system do much of the daily basic monitoring for you.  When the VMS detects that a machine's vibration level is exceeding one of the thresholds, it automatically tells you of the event so that you can take action.

VMS indicates alert conditions in several ways to allow you to quickly and easily navigate to the machine that is having a problem and to see visually when and why the alert condition was raised.  In addition to the system wide-alert log, VMS presents four different alert indications.  The first of these are Dynamic Alert Icons on the Navigation Tree, discussed in Section

Any time a vibration sample exceeds an alarm or warning threshold in one or more monitoring bands, an alert is generated and presented as an alarm icon, or warning icon on the monitoring band, monitoring location, machine and facility levels in the Navigation Tree.

If there are multiple alerts triggered at the same level in the Navigation Tree, the higher level will propagate up the tree to the next level.  For example, if the warning threshold is breached in a band on one machine and the Alarm threshold is breached in a band on another machine, then the alert level for the facility as a whole will be set to the alarm level and will be indicated with the alarm icon.

The nearby Navigation Tree shows an example where one machine--Chiller One--has triggered and alarm and a second machine--Chiller Two--has triggered a warning, so the alert level of the West Campus HVAC Plant as a whole shows as an alarm.

The alert icons are dynamic and only show the alert level of the most recent vibration sample.  As such, if the machine temporarily exceeds a threshold vibration level and then returns to normal operation, the alert icon will show up briefly and then go away.  In this way, the alert icons in the Navigation Tree always give you a snapshot of the current state of your machines.

You can learn much more about KCF Technologies' SmartDiagnostics® technology here.

Wireless Sensors Work

In the world of vibration monitoring, wireless sensors can provide a cost-effective alternative to traditional machine monitoring methods.

The following article, authored by KCF Technologies employees Christopher Shannon and Matt Cowen, was published in the June/July 2013 issue of Uptime Magazine.

SmartDiagnostics® sensor
on a compressor.
Traditionally, machine vibration monitoring is performed in two ways: machines can be periodically monitored by utilizing a temporarily mounted sensor and a portable analyzer machine, or machines can be continuously monitored by permanently mounting sensors and wiring them into a high end diagnostic system in the plant.

The advantage of a portable system is that it can cost less to procure and install since there is no permanent wiring required. However, if a facility decides to hire an outside firm, even this option can be costly, running between $600 and $1,200 per day while still providing some level of predictive monitoring. The disadvantage of a portable system is that machine problems do not follow a schedule and there is a very real possibility that a machine can develop problems or even fail between the periodic assessments.

Permanently mounted sensor systems attempt to address the issues presented by portable systems, but they do so at a very high cost.  Acquiring and installing a permanent system can run into the hundreds of thousands of dollars when you factor in the costs of the sensors, diagnostic machine and software, and the installation and maintenance of long wire runs that are necessary to power the sensors and collect the vibration data. These costs can dramatically affect the return on investment (ROI) of continuous machine vibration monitoring for predictive maintenance and put such systems beyond the financial reach of most companies.

While permanent machine monitoring has traditionally been performed using wired sensors, costs for wiring vibration sensors are high, ranging from $50 to $100 per foot. Wire installation costs are a driving factor that limits the affordability of vibration monitoring. Wireless sensors address this cost issue.  Additionally, wireless sensors offer to simplify sensor installation, reduce maintenance associated with wiring faults, permit new sensor locations that would not have otherwise been accessible with wired sensors, and offer greater flexibility with easy installation or removal, as required.

In summary, wireless sensors have the promise to make vibration monitoring practical for most companies.  Read the rest of the article on the Uptime Magazine website.

Photo by Matt Cowen/KCF Technologies.  All rights reserved.

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