Archive | May, 2008


6:00 am
May 1, 2008
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Hushing Up A Serious Problem: Gaseous Noise

0508_noise_11No joke, it’s getting a lot quieter out there. You, your equipment and your processes have a number of cutting-edge noise attenuation solutions to thank for it.

Uncontrolled noise in process operations is a serious problem. Unresolved issues with noise can lead to health problems, vibration and, in the most extreme cases, equipment damage. All noise attenuation solutions are not created equal, and no one product will be effective in every situation. It is, therefore, important to understand what is creating noise before attempting to fix the problem.

Noise 101
The most significant factor impacting noise is fluid velocity—a significant rise in velocity can produce noise beyond safe limits.

When fluid travels through a conventional singleseated, globe-style valve, a “vena contracta” (point of narrowest flow restriction) develops directly downstream of the narrowest throttling point. At this point the fluid reaches a minimum pressure and maximum velocity that rapidly recovers to a lower pressure than the inlet pressure. When fluid pressure in the valve drops, the fluid velocity rises—this is called the “Bernoulli Principle.” As the velocity of the fluid increases, the noise generated by turbulence in the fluid also increases (see Figs. 1 and 2).


The driving force behind velocity and, accordingly, noise, is the difference between the inlet pressure and outlet pressure, which represent the energy available to generate noise. When this difference is low, the energy contained in the fluid stream will be low and the noise that is generated typically will be low as well. Each noise solution will have a range of pressure drops where the design is most effective.

0508_noise_fig31Noise attenuation solutions
Most globe valve attenuation solutions use cages with a variety of designs available on the market. A typical solution with drilled holes is shown in Fig. 3. (Pressure through a multi-stage valve is shown in Fig. 4.) Different solutions using one of the noise reduction mechanisms listed in the accompanying sidebar—or a combination of such mechanisms— also are available.

Reducing pressure while controlling velocity is a common method for reducing noise, accomplished by dividing a large pressure drop into smaller pressure steps, which will produce far lower velocities at each step. For example, a sudden contraction followed by a sudden expansion can decrease pressure by creating turbulent zones in the fluid flow. The turbulence takes energy out of the fluid in the form of pressure. This is the effect primarily used by orifice plates. Using several orifice plates will create a high overall pressure drop while generating lower velocities than would a single plate designed to create the same pressure drop.

Design solutions, such as small flow passages, also can help reduce noise. Small passages accentuate the friction formed by the passage walls. As the passage grows smaller more pressure is required to force the fluid to flow.

A mutual impingement design also will reduce pressure without adding velocity to the flow. Mutual impingement is created when two flows impact at 180°, forming a highly turbulent zone that dissipates energy.

Sudden turns in the fluid path are another way to cause the pressure in the fluid to drop. The angle of the turn can have a dramatic effect on the energy loss—angles sharper than 90° are difficult to manufacture but are more effective in reducing pressure.

An acoustical attenuation solution can provide a barrier that blocks noise. This can be accomplished in a number of ways, including insulating the pipe and increasing the distance to the noise source.

Careful engineering of the noise solution includes evaluating any existing attenuation. Often thermal pipe insulation can be used in the evaluation of the noise to reduce the predicted noise level without adding cost to the system.

Understanding the Peak Frequency Effect can offer alternative options for decreasing noise levels. Most noise in a control valve produces a range of frequencies that have a bell curve type distribution and a peak frequency—changes in the geometry of the valve design will shift this peak. It is possible to shift this frequency out of the range of human hearing, which lowers the perceived noise and damage to human organs. Shifting the peak higher also reduces the level of noise that will pass through the pipe, which has a naturally low frequency. A common way to raise the peak frequency is to make smaller outlet holes in the noise control device—cutting a hole diameter in half can lower the overall noise level by up to five decibels. This type of solution is available from all major control valve manufacturers as a cage with small holes.

0508_noise_fig41WaveCracker® technology is a patented technology that reduces noise as flow passes through irregularly shaped cross sections. Tests have shown this technology can effectively reduce noise by more than 10 decibels. WaveCracker works by forming an irregular cross section shape. Sound waves reflecting off the walls of the passage have irregular patterns that cause the sound pressure wave to lose intensity as it moves down the passage (see Fig. 5).

One cause of noise could be harmonic vibration—something that occurs when the valve and pipe approach a common frequency. This problem is characterized by a tell-tale “screech,” where a single frequency is pronounced. Because screech occurs when the frequency of the valve and pipe match, it is not easily predicted.

Noise also can worsen due to reflective surfaces that amplify noise coming from a pipe. A single, flat surface near a valve, like a concrete floor, can add three decibels. Two hard, flat surfaces (like a floor and flat ceiling) that are parallel to one another will add more than six decibels. Adding walls, a ceiling and a floor can add 30 to 40 decibels.

Noise prediction
Careful noise predictions will prevent most noisy applications. A number of noise prediction techniques exist with varying degrees of accuracy for different applications. Unfortunately, no standard exists that is the most accurate for all possible conditions.

Most manufacturers have proprietary techniques that will produce acceptable prediction under a range of conditions and with equipment the manufacturer is familiar with. When used outside the acceptable range or with other equipment, however, proprietary techniques can be significantly different than actual noise produced.

0508_noise_fig51The IEC committee has developed the IEC standard 60543-8-2 in an effort to provide an accurate standard that can be used to compare products from different manufacturers. Although it’s not perfect, this method does create a clear baseline that can be used to compare equipment from a variety of suppliers. If noise control is critical around your operations, it is important to study all factors, such as flow conditions, valve design, system installation and available noise prediction methods.

Before you buy…
Before purchasing expensive noise suppression equipment, you should ask yourself a few important questions:

  • How much noise attenuation is actually required?
  • What are the low-cost alternatives to noise attenuation?
  • And, if noise attenuation devices are necessary, what lower-cost equipment can be specified?

If the predicted sound pressure level (SPL) exceeds 85 or 90 dBA, noise suppression devices should be considered. If the noise is not associated with equipment damage and is located in a remote location away from people, however, higher noise levels may be acceptable. Other possible low-cost alternatives to noise suppression are piping insulation, discharging the valve into a vessel, relocating the noise source outside an enclosed area, reversing the flow direction through the valve and reducing the pressure drop across the valve.

When noise levels are critical, it always will be important to consult a control valve noise expert. In these cases, the expert will need to gather information and data on your specific application. The more information you are able to provide, the higher the expert’s success rate will be. MT

Selecting The Right Noise Attenuation Solution

  • The Flowserve Tigertooth design is most effective at high pressure drops where it reduces sound pressure levels using the sudden expansion and contraction phenomenon. The design features highly-engineered concentric grooves—or teeth—machined into the face and backside of a series of circular stacked discs that form the seat retainer. Legs separate one disc from another, providing a gap between individual discs, forming flow passages. The passages are self-cleaning, and grow wider as the fluid passes to allow large solids easy passage through the trim.
  • Flowserve MegaStream technology (like that shown in the cutaway in Fig. 3) employs a heavy-duty drilledhole seat retainer with up to seven stages to lower noise levels. It is one of the most common solutions to control valve noise. Pressure drops are distributed between the throttling point of the plug and seat ring as well as the stages of the retainer. Each stage is designed to take a small pressure drop, avoiding the high velocities present in single-throttling-point trims. Fluid expansion and velocity are controlled by increasing the flow areas of each subsequent stage. Cutting the MegaStream retainer hole size in half will reduce the noise level by up to 7 dBA through frequency shifting effects.
  • Flowserve Type I Trim reduces noise generated by moderate pressure drops. By changing only a few parts, the noise reducing cage can be added to the standard valve without special plugs or seat rings. Type II Trim adds a skirt-guided, drilled-hole plug to the attenuators used in the Type I design. The Type II design is most effective at reducing noise generated by moderate to high pressure drops. Type III Trim uses the same skirt-guided, drilled-hole plug as the Type II design and adds a heavy-duty drilled-hole cage. The Type III system is most effective at reducing noise generated by higher pressure drops.
  • The Flowserve RLS-System Trim design tightly controls fluid expansion and velocity for maximum efficiency at all plug positions. The four-flange body provides more pressure drops, and small holes in each stage create frequency shifting, producing lower-noise levels while attenuating upstream noise.
  • Flowserve XStream Trim eliminates noise in moderate to high pressure drops. Using four drilled hole stages and a contoured plug, the XStream provides noise reduction and turndown. Using small holes in each stage for frequency shifting, the XStream produces lower noise levels while attenuating upstream noise.
  • Multi-Hole Trim uses a cost-effective, skirt-guided plug head with drilled holes and reduces noise generated by moderate pressure drops. This trim also generates less noise than conventional designs by using small holes in the plug skirt to shift the frequency and lower noise. The Flowserve SilentPac Trim design also reduces noise generated by moderate pressure drops. The noise reducing cage can be added to the standard valve without special plugs or seat rings.
  • Z-Trim combines the benefits of an advanced control valve with the simplicity of a ball valve. It is most effective with low- to medium-pressure drops, and excels at eliminating noise in high-flow services. The simple design reduces noise by passing the fluid through as many as five stages of pressure reduction.
  • Anti-noise plates can also be installed downstream of a control valve as a simple, cost effective way to reduce control valve noise without making any changes to the valve. Plates provide lower noise by lowering turbulence, providing back pressure to the valve and providing attenuation on noise generated inside the valve. Plates are most effective in low- to medium-pressure drop application.
  • An all-in-one solution For the most demanding applications, Flowserve’s Valtek Stealth® design combines all of the most effective noise- and pressure-control mechanisms into one product. The Stealth trim is produced by laser cutting circular discs to form fluid passageways and then braising the discs together to form a seat retainer. Three different discs are cut and matched together to form a flow path set. A number of disc sets are then stacked together and the whole assembly is brazed together to form a stack.

    Similar to Tiger Tooth, an important mechanism reducing the pressure in Stealth trim is the sudden expansion and contraction phenomenon that takes place as the flow passes over the teeth. The Stealth trim also takes advantage of frequency shifting by providing small outlet holes. Stealth also features WaveCracker technology that provides extra noise attenuation without creating additional pressure drops in the valve. Angled exit flow paths increase the flow capacity of the valve, reduce exit turbulence and lower noise. Other mechanisms at work in the Stealth design are pressure control, velocity control, attenuation, frequency shifting and noise cancellation.

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6:00 am
May 1, 2008
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Solution Spotlight: IR: A Key Diagnostic Tool In PdM Programs

Being proactive is what predictive maintenance is all about.

With coal-fired plants generating a substantial percentage of the electricity produced in the United States, it’s vital to ensure their reliability. Keeping such a plant up and running calls for continual monitoring of equipment and maintenance planning. Even the smallest of components have the potential to shut down operations. That’s why infrared thermography (IR) can be such a powerful tool around these facilities.


IR technology
Thermal or infrared energy is light that is not visible because its wavelength is too long to be detected by the human eye. It is the part of the electromagnetic spectrum that we perceive as heat. Unlike visible light, in the infrared world, everything with a temperature above absolute zero emits heat. Even very cold objects, including ice cubes, emit infrared. The higher the object’s temperature, the greater the infrared radiation emitted. IR allows technicians to see what their natural eye cannot.

Infrared cameras produce images of invisible infrared or “heat” radiation and provide precise non-contact temperature measurement capabilities. Nearly everything gets hot before it fails, making infrared cameras extremely cost-effective and valuable diagnostic tools in many diverse applications. And, as businesses strive to improve manufacturing efficiencies, manage energy consumption, improve product quality and enhance worker safety, new infrared thermographic applications continually emerge.

Mirant Mid-Atlantic, LLC is one organization that has recognized the value of IR in its business. The company generates electricity for various localities in the mid- Atlantic region of the U.S. It owns four power plants in the Washington D.C. area and the coal-fired Chalk Point station in Maryland handles a large portion of the electricity generation for the mid-Atlantic assets.

The Chalk Point facility’s maintenance organization is responsible for ensuring that processing equipment performs as required. Infrared cameras now play a big role in condition monitoring and overall predictive maintenance. Before IR, point measurement was the only type of temperature gauge used. There was no way to look at a whole area or piece of equipment and anomalies were not easily identified.

Mirant Mid-Atlantic currently uses FLIR’s ThermaCAM® T400 infrared cameras as part of its PdM efforts. The information obtained with the T400 is furnished to schedulers and planners so they know what equipment to schedule for repair and when. Having this information gives them the necessary lead-time to order parts and schedule maintenance. The camera also helps identify equipment that does not need maintenance. Eliminating properly functioning equipment from the maintenance list saves time and money.

In these power gen operations, coal is transported from storage to the generating facility by conveyor belt. The FLIR cameras are used to identify problems with pulleys, gearbox drives and roller bearings along the conveyor belts. They also are used to find leaking valves, identify blockages of coal going into the boiler and in boiler tubes. The infrared technology and resulting data lets technicians locate and determine the severity of faults and plan their maintenance activities accordingly.

Maintenance technicians cover a lot of ground in surveying equipment in these operations. The T400 is small and lightweight, making it easy for them to get the job done. The large viewing window and lenses that rotate make it possible to capture images when equipment is in difficult-to-reach places.

Real results
Results of thermographic inspections vary from equipment to equipment, but understanding the impact of even one piece of equipment or component helps illustrate the benefits of this powerful technology in a PdM program.

A study done by Mirant Mid-Atlantic found that by fixing a typical leaking valve, it saved an average of $5700 annually. In 2007, the company identified 187 valves. The cost of an infrared camera and other diagnostic tools is clearly a solid investment when fixing leaking valves. While the problem may have seemed to be a small one, solving it delivered savings of more than a million dollars.

Catastrophic failure of a conveyor belt also could have an enormous impact on production and costs. Although reserve coal for such situations is available, without new coal entering production, these reserves would quickly diminish and cause electric generation downtime. The ability to see problems before they become catastrophic allows Mirant Mid-Atlantic’s maintenance team to plan and schedule repairs as needed, helping save in terms of maintenance expenditures, downtime and lost production. MT

FLIR Systems, Inc.
Billerica, MA

About FLIR

FLIR Systems, Inc. designs, manufactures and markets infrared imaging systems worldwide for a variety of thermographic and imaging applications. FLIR’s thermography products are being used in diverse applications, including predictive maintenance, condition monitoring, non-destructive testing, and research and development and manufacturing process control. To learn more, go to

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6:00 am
May 1, 2008
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Uptime: Meeting Of The Minds


Bob Williamson, Contributing Editor

Rosemont, IL in April could never be confused with the sunny south. Nor will it ever be classified as a relaxing resort, entertainment hub or exotic portof- call. Nonetheless, despite having made a weeklong pilgrimage to Rosemont around this time for the past five years, I keep coming back for more.

This year, as usual, the huge “buffet” I have grown accustomed to finding in Rosemont did not disappoint. Over time, it has continued to serve up a vast selection of the tastiest, most nutritious items for our times. With many places to visit, the lines were again short and the crowds, representing a cross-section of people from all over North America and the world, were very friendly. Year after year, those of us who join in this pilgrimage spend our time sharing with each other about our interests, our work and the many and varied mysteries in our lives.

No, my annual trip to Rosemont is not a family outing. It’s not recreation. It’s not a vacation. What it is, however, is one of the best work-related venues available to those in our industry. It’s where participants— regardless of company and specific job titles and responsibilities—can get fired up about reliability, get excited about change and get answers to most, if not all, of their maintenance and reliability mysteries. The Maintenance & Reliability Technology Summit (MARTS) event provides so much for so many. This year, as always, it was a true meeting of the minds, focused on improving plant, facility and equipment performance and reliability.

Plenty of offerings
This April, I met many people who had been reading my columns for years—and many more who had just begun reading them. They came from a wide variety of industry sectors, including manufacturing industries, power & utilities, petro-chemical processing, mining and production, higher education, facility engineering and more. More than 190 companies were represented, from 36 states, five Canadian provinces and two from outside North America.

The “nutritious buffet” went well beyond the meals to include something for every maintenance and reliability person in attendance:

  • Nearly 30 highly experienced and insightful professionals presented in 11 pre/post-conference workshops and 47 conference sessions on 30 different subjects.
  • Forty exhibitors displayed state-of-the-art products and services for improving maintenance and reliability.
  • For those seeking another competitive advantage, MARTS provided the CLS (Certified Lubrication Specialist) review workshop and an on-site exam, and the CMRP (Certified Maintenance & Reliability Professional) review workshop and on-site exam sponsored by the Society of Maintenance & Reliability Professionals (SMRP).

Come to think of it, MARTS is not just a meeting of the minds; it’s a veritable “one-stop shopping” destination for today’s (and tomorrow’s) maintenance and reliability leaders!

Plenty of take-aways
I met people from many different industries and locations who were looking for something specific, be it in the form of a tools, a strategy or just a new way to help improve their plant or facility performance and reliability. Some were new to our profession, some were old hands. Some of the participants were there with teams of others from their respective companies, dividing up among the sessions to learn about as many answers/solutions as they possibly could in a few short days—answers/solutions that they could take back to their plants and begin sharing with others.

While I wasn’t able to sit in on all of the sessions, I listened to a range of variety of presenters who told of their maintenance and reliability challenges and how they successfully addressed them. I heard from seasoned veterans and leading experts—people who I have followed throughout my own career—as they talked with authority about maintenance and reliability best practices.

Session participants asked some very hard-hitting questions about problems or opportunities back at their workplace—and expected hard-hitting answers. They received invaluable advice. MARTS sessions not only covered the nuts-and-bolts topics, they also covered some of the “soft” side of maintenance and reliability—i.e., people, organizations, training and work methods. Here are just a few of the nuggets I gleaned from MARTS 2008:

  • A “business case for reliability” helps increase shareholders’ return on assets (ROA).
  • Functional separation in organizations leads to disconnected improvement strategies.
  • Get the basics right first. Avoid the “new technology/ tool traps.”
  • Standardized plant-specific training for operations and maintenance improves performance.
  • PM optimization begins with eliminating nonvalue- adding tasks and adjusting frequencies.
  • PM optimization has removed 12,000 maintenance hours and improved reliability.
  • Involve operators in startup checks, minor maintenance and end-of-shift cleaning/ inspection.
  • Maintenance apprenticeship programs are restarting to stem the Baby-Boomer retirements.
  • “5S” methods “error-proof” the workplace and increase employee efficiency, safety and quality of workmanship.
  • 70% of mechanical failures and 20% of energy costs can be attributed to the lubrication program.
  • Operations is not the “customer” and maintenance is not the “supplier.” These departments are partners for capacity and reliability assurance.
  • Partnership organizations improve equipment and process reliability and lower life-cycle costs.
  • Unreliable equipment leads to higher costs and lower profits. Oil and gas prices are higher in part because of refinery problems and pipeline leaks in North America.
  • Hydraulic fluid should last forever. Cleanliness, lack of moisture and temperature prevent this.
  • Firefighters reflect a good model for maintenance and reliability, through their ready-state of preparedness and controlled work processes in the context of absolute chaos.
  • Visual cause-and-effect diagrams help solve complex problems and improve communications.
  • Reliability is a common goal for quality, safety, environmental and equipment performance.

Plenty of tools
“Tools you can use” is a term that frequently came to mind as I was sitting in the conference sessions. In other words, what all of us were picking up at MARTS were real tools we could take back to our jobs and immediately put to use. Sometimes these “tools” were the ones that could be used to pry some of the old ideas and paradigms out of the rut we often find ourselves in back at work.

The well-prepared exhibitors also provided tools and methods for addressing specific performance issues with modern and not-so-modern, plants and facilities. Smart tools and smart equipment incorporating some of the “smartest” technologies in the marketplace were demonstrated everywhere we looked in the exhibit hall.

An added bonus at this year’s MARTS was the participation of the 2007 North American Maintenance Excellence (NAME) Award winners. Representatives of the two honored plants—Alcoa Mt. Holly, SC, and Baldor Electric/Reliance Dodge, Marion, NC—discussed their “winning ways.” In both cases, these operations had created a “reliability culture” using the proven methods of Total Productive Maintenance (TPM) to achieve best-in-class equipment and process reliability. The “lessons learned” from past NAME Award winners included examples of operational excellence focused on a foundation of health, safety and environmental plans; clear organizational and strategic planning goals; reliability engineering and defect elimination teams; operators involved in routine maintenance; and asset reliability as a shared responsibility between manufacturing and maintenance.

Plenty of satisfaction
The part of this two-day conference and the two days of pre- and post-conference workshops that impressed me the most was how “hungry” for knowledge the participants were. As noted previously, I talked with countless attendees who were looking for something specific—something that they could put to work back at their facilities to help make their jobs easier, their plants more reliable and their businesses more competitive. Their gnawing hunger certainly appeared to be satisfied by week’s end!

Thanks to you
To all of you who attended and presented at MARTS 2008, I wish to thank you for sharing your insights with me and with each other. Every year at this event, I learn so much about your various challenges—and so much about the effective solutions that you’re implementing to address those challenge. As a contributing editor, your sharing with me is extremely important. It helps me to focus more accurately on the types of issues that confront you day-in and day-out. Everyone who participated (regardless of your role) added great value to this and future MARTS—as well as future issues of this magazine. I am already looking forward to meeting you next year in Rosemont to learn even more from you.

This year’s meeting of the minds may have come to a close, but the tools, the ideas and the insights are no doubt being put to good use by all of you to make your jobs easier and more productive. What you learned at this year’s MARTS (and those of past years) will contribute to your own organization’s performance, reliability profitability and growth, as well as bolster your respective countries’ competitiveness in a difficult global economy.

We’ll see you at MARTS 2009. MT

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6:00 am
May 1, 2008
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Balancing and Vibration Test Solutions For Air Cycle Machines

If you’ve ever flown anywhere (or plan to in the future), you’ll appreciate the importance of adequate and reliable balancing and testing of this equipment

Modern jetliners rely on air cycle machines to provide air conditioning throughout the passenger cabin. Not only is this provision available on the ground, where outside tarmac temperatures can reach well over 100 F, but also in flight at altitudes reaching over 30,000 feet and temperatures reaching below -30 F. Air cycle machines are a vital component in maintaining a safe and comfortable cabin environment for millions of passengers around the globe. This means big business for OEMs and overhaul facilities worldwide.

The air cycle machines (ACMs) consist of three main components: fan, compressor and turbine. These three components are mated to a single shaft and support by two journal air bearings, with typical operating speeds between 30,000 and 50,000 rpm.

0508_vibration_11The problem
Each rotating component contains an element of unbalance. Unbalance— an uneven weight distribution—is caused by factors in the manufacturing and assembly processes. This unbalance causes vibration that can lead to stress, fatigue, noise and, ultimately, bearing damage during operation. Therefore, ACMs must be carefully balanced and undergo vibration analysis before entering service to ensure long life and reliability.

Balancing of the ACM components requires a small horizontal balancing machine. The compressor, turbine and fan components are balanced individually using tooling arbors. (Editor’s Note: Schenck’s RS1 soft-bearing balancing machine can accommodate a majority of the ACM components, including the shafts, and provides flexibility for a service facility to balance other smaller components. For larger components with lower tolerances and those using tooling, an HM2 balancing machine is suitable for the balancing tasks.) Service facilities may have specific requirements and ACM models, so balancing solutions must be determined based on individual needs.

Vibration analysis
Before an ACM is entered into service, it has to pass several tests specified by the OEMs for the individual ACM, including pressure tests, break-in tests, performance tests and balance verification tests. During the tests, numerous parameters are recorded and monitored. Some of the tests require vibration analysis for which Schenck also provides testing equipment.

0508_vibration_21Vibration analysis includes the measurement of housing vibration and shaft excursion. Housing vibration can be measured using accelerometers. Shaft excursion, also called relative shaft vibration, is measured using two non-contacting displacement pickups (Eddy Current Sensors). Displacement sensors must be installed with a slight shaft clearance perpendicular to each other. The sensitivity of the sensors is dependent upon shaft material and shaft dimensions, so this has to be determined for each type of ACM.

OEM manuals require the monitoring of two components of the shaft excursion signal: synchronous vibration, the component related to the running speed of the rotor, and non-synchronous vibration, vibration not related to the running speed. To provide these readings, the vibration measuring unit uses a tracking filter. A reference signal for speed and phase is provided by laser if the shaft end of the inlet fan is accessible. Should the shaft end be inaccessible, the use of a magnetic sensor is possible providing that the shaft material is steel and incorporates a keyway or other trigger feature. Synchronous vibration is caused primarily by the residual unbalance of the rotor or misalignment, where the components are not mounted concentric and perpendicular to the shaft. If the synchronous vibration exceeds a certain limit, the assembly must be trim balanced.

Synchronous vibration readings (amplitude and phase) are taken at different running speeds. From these readings, an “optimization” procedure is used to calculate the correction weights to minimize the vibration for the complete speed range. Corrections are then performed at the shaft ends. Non-synchronous vibration is an indication of bearing instabilities. In this case, vibration that exceeds tolerance requires the unit to be disassembled and checked. MT

Roland Kewitsch is manager of the Vibration Analysis and Condition Monitoring Group at Schenck Trebel Corporation in Deer Park, NY. His experience in the field spans more than 20 years both in Europe and the USA. E-mail:

Jan Dittmar is senior applications engineer with the Schenck Jet Engine and Aerospace Group in Deer Park, NY. E-mail:

Schenck Trebel Corporation Deer Park, NY, US

Providing Complete Solutions…

Backed by over 100 years of balancing experience, Schenck Trebel provides a complete line of vertical and horizontal balancing machines for the production, maintenance and repair of any rotating component—from a fraction of a gram to over 600,000 lbs. The company offers a range of vibration analysis equipment, including field balancing machines, balancing tooling and condition monitors for precision rotor performance. Schenck’s nationwide Balancing Technology Centers also provide rotor balancing services and various on-site services, including predictive maintenance and on-line condition monitoring services for critical equipment. But, that’s not all.

Schenck’s total support program goes beyond balancing to provide equipment and technical services, balancing certification, on-site and off-site seminars and in-house balancing services. With more than 60,000 machine installations worldwide, Schenck can offer the right solution. For details, visit:

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6:00 am
May 1, 2008
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Viewpoint: A Lasting Solution: Closer Than You Think


Susan Wasley, BE&K Director of Special Programs

Where on earth will you find enough skilled labor to keep your plant running or finish your next job? Perhaps you should start looking in your own backyard.

Available labor in the maintenance and reliability arena appears to have hit a critical low— and the situation seems to be growing grimmer by the day! Yet, the pool of 80 million women in the American work force has barely been tapped to help fill the void. These days, industry experts tell us, fewer than 20,000 women actually are “in the trenches turning wrenches.” What’s really the problem here?

Could it be that women don’t want to work in traditionally male-dominated trades? Research tells us that they want the same thing men do from their jobs—good pay, fair treatment, a chance for growth and an opportunity for a better life. The fact is, very few young women are encouraged to explore careers in the skilled trades. High school educators and career tech advisors wrongly assume that “girls” aren’t interested in “those types of jobs.” But, when young women learn the facts about crafts training, especially about the earning potential, they are very interested, indeed. Thus, we need to make sure teachers and advisers have the facts and keep an open mind about nontraditional employment options. Could it be a matter of women not being able to do the work? Archeological research on prehistoric humans indicates that males and females participated equally in chores of daily living, including the construction and maintenance of the family’s shelter. As recently as World War II, women proved they could succeed in all types non-traditional roles, performing every kind of job America had to offer while the men went to battle. It worked then because everyone agreed that in order to win the war, jobs had to get done. Americans successfully united to march to the beat of a patriotic drum. Women were recruited, hired, trained and compensated well for doing what was traditionally referred to as men’s work. They were proud of their work and men were proud of them!

Or, could the problem be that men simply don’t care to have women in the skilled trades? What the vast majority of men working in these areas really care about are safety, quality and doing a job right the first time, every time. That’s what the vast majority of women care about as well. When given the right training, mentoring and opportunity, they, like men, work safely and produce consistently high-quality work. Proper training allows everyone—regardless of gender—to focus on what all people on the job should be focused on: the work!

Today, our nation faces a different kind of threat than that posed by World War II—an economic one. If we don’t tap into a new and robust labor pool, many of our industries and much of our infrastructure will suffer and our economy will continue its downward spiral. The solution lives and breathes in homes across America, but we must stop pointing fingers at one another and unite just as we did more than 60 years ago. Solving the problem lies in the building of partnerships among industry, education, government and communities—and in tapping under-utilized labor pools.

If your operations are desperately seeking skilled labor, prepare for the problem to get worse. It will! Take action now. Recruiting and training women is a short-term, yet powerful solution with lasting benefits. The skilled trades need good people and women need good-paying jobs. Let’s begin looking in our own backyards for a way to end this labor crisis. MT

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