Archive | 2008

352

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November 1, 2008
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Utilities Manager: Uptime, Availability, Reliability…

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William C. Livoti

What do we mean by “uptime,” “availability” and “reliability,” and how do these terms figure into our quest for energy-efficient equipment systems?

Uptime refers to a plant’s ability to remain on line/ produce product. With an uptime rating of 100% as maximum, any unscheduled downtime will reduce the rating. We’ve all experienced unscheduled plant shutdowns. Since such events affect our uptime rate, it goes without saying that they have an impact on an operation’s bottom line.

Some plants/industries operate at varying capacity or loads. Availability for these sites becomes an issue when the plant cannot respond to increased load or capacity on demand. Again, this impacts an operation’s bottom line.

While different industries have varying perceptions of reliability based on their specific operations, given the background of this magazine’s readers, there’s little need to define the term here. What’s important to understand, though, is that equipment reliability goes hand in hand with uptime and availability—and energy efficiency. All of these things impact an operation’s bottom line.

So what are we really talking about? It boils down to sustainable growth in perhaps the most dynamic economic times in modern history. In other words, how do we maximize uptime, availability, reliability—and energy efficiency? Speaking strictly from an equipment perspective, the answer is “by optimizing our systems/ equipment.” If your operation is anything like countless others throughout industry, ample opportunities await you. Take, for example the following symptoms that indicate potential for improvement in pumping systems:

  • Systems controlled by throttle valves/dampers;
  • Recirculation lines normally open;
  • Cavitation noise at valves or pumps;
  • Multiple parallel pump systems with the same number of pumps always operating;
  • Constant pump operation in a batch environment or frequent cycle batch operation in a continuous process;
  • Systems that have undergone a change in function;
  • High system maintenance;
  • Motors that trip out.

All of these symptoms could impact your plant operation and ultimately your company’s bottom line. In many cases, these system issues can be corrected easily. If you don’t need a pump, shut it down. If a motor is tripping, you may need to throttle the discharge valve as an interim corrective action, then plan to investigate root cause as time allows. There are plenty of other simple, cost-effective solutions.

Your own bottom line If your operations fail to address existing issues that impact plant uptime, availability, reliability—and energy efficiency—there is a very good possibility your company may not survive the ongoing economic crisis in which we’ve found ourselves. Consider these two facts:

  • Since 1962, of the 1000 largest companies by size, only 160 stayed in that group.
  • Of S&P 500 companies in 1957, only 74 were still in existence in 1998 and only 12 gained in position.

Why? For the most part, it was companies failing to adapt to the changing times.

It should be fairly clear by now, in order to survive these changing/challenging times, we must adapt. “Business as usual” will not provide stability or sustainable growth.

Think uptime, availability, reliability—and optimized systems. UM


Bill Livoti is our new UTILITIES MANAGER columnist, is senior principal engineer for Power Generation and Fluid Handling with Baldor Electric Company. He also is vice chair of the Pump System Matter initiative. Continue Reading →

223

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November 1, 2008
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Utilities Manager: Fighting Friction In Rotating Equipment

Any time you knock out friction around your operations, you’re on your way to reducing energy consumption. Bearings are a good place to start.

Whenever rotating machinery is turning, friction can become a “spoiler”—potentially threatening the operation, reliability, productivity and service life of assets. For bearings, friction is problematic, as it can contribute to increased wear, generate unwanted heat and higher operating temperatures, limit speeds and power and reduce overall energy efficiency. The mission is to mitigate the negative effects.

Anti-friction rolling bearings (ball and roller types) provide a first step on the road to solutions. In contrast to plain (or sliding) bearings, with their sliding and frictionprone surfaces, ball and roller bearings inherently will minimize friction by removing almost all sliding between bearing surfaces and replacing the major internal contact areas with rolling interfaces. However, even with the benefits from one element rolling (not sliding) over another, some friction will occur with ball and roller bearings.

Specifically, multiple sources of friction can be pinpointed. Friction can be generated at the rolling contacts, in the contact areas between rolling elements and cage (as well as in the guiding surfaces for the rolling elements or the cage), in the lubricant and in contact seals where applicable.

Even though industry has devised calculations to determine “frictional moments” in advance, friction always can increase. The problem, though, can be managed by taking advantage of friction-reducing materials and designs for bearings and the proper selection and quantity of lubrication.

1108_fighting_img1Getting your bearings
In keeping friction at bay, rolling bearings must always be subjected at least to a given minimum load to allow for proper rolling element rotation and lubricant film formation in rolling contact areas. A general rule of thumb: Loads corresponding to roughly 0.02 times the dynamic radial load rating should be imposed on roller bearings and loads corresponding to 0.01 times the dynamic radial load rating should be placed on ball bearings.

Generally, roller bearings can support heavier loads than similarly sized ball bearings, and bearings incorporating a full complement of rolling elements can accommodate heavier loads than corresponding caged bearings. Ball bearings are used mostly where loads will be relatively light or moderate. For heavy loads and where shaft diameters are large, roller bearings typically will be specified.

Once the ideal load has been established for proper rotation and lubricant film formation, opportunities to minimize friction can be developed with the bearings themselves. For example, materials used to manufacture rolling bearing rings, rolling elements and cages can play a vital role in reducing the amount of friction. Bearing grade ceramics (silicon nitride) have helped create the category of hybrid bearings, which combine the silicon nitride rolling elements with steel rings to exhibit demonstrable advantages compared with conventional all-steel bearing counterparts. Among benefits, the ceramic balls are roughly 40% less dense than steel balls. This reduces centrifugal force and enables the bearings to run faster and with likely less friction at higher speeds.

In addition, due to higher values for the modulus of elasticity of ceramics and the increased stiffness this provides, hybrid bearings feature smaller contact areas. This, too, favors a reduction in the rolling and sliding friction components.

As another example of a material solution, polymer cages introduce superior friction properties compared with conventional steel or brass counterparts. Such PEEK (polyetheretherketone) cages additionally can operate at higher speeds, perform at higher temperatures and offer enhanced resistance to aggressive agents.

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Specialized coatings similarly can be enlisted in the fight against friction. Examples include a low-friction coating that can be applied on a bearing’s inner surfaces. Compared with standard uncoated types, bearings with the coating will generate less friction (and resulting heat) and can better tolerate potential damage from contamination and marginal lubrication. (They also are better equipped to resist wear, operate at higher speeds, accommodate higher loads and perform even during periods of insufficient lubrication.)

Bearing engineering, too, has kept pace in efforts to reduce friction. An entirely new generation of “energy-effi- cient” bearings has been developed as part of a system solution. They incorporate an optimized bearing raceway shape to minimize friction torque (or friction loss); a uniquely compatible grease minimizes friction torque associated with grease thickener and oil viscosity; and a polymer cage serves to reduce ball cage friction loss and channels more effective grease migration inside the bearing.

Once any bearing is installed and operating, users should be aware of the negative effects relating to the issues of clearance and/or misalignment. When bearing internal clearance is reduced due to high operating temperatures or high speed limits, friction will increase. Proper internal clearance should always be maintained. Misalignment, too, typically will increase friction, and self-aligning bearings offer one remedy to help solve the problem.

Looking at lubricants
Lubricants for bearings primarily deliver a separating film between a bearing’s rolling elements, raceways and cages. The film serves to prevent metal-to-metal contact and the resulting friction that otherwise would generate excessive heat that could cause wear, metal fatigue and potential fusing of the bearing contact surfaces. (Adequate lubrication for bearings further acts to inhibit wear and corrosion and help guard against contamination damage.)

The friction torque in a bearing will be lowest with a quantity of the lubricant with the correct viscosity (relative resistance to flow) sufficient only to form a film over the contacting surfaces. The friction will increase with greater quantity and/or high viscosity of lubricant. With more than just enough to form a film, the friction torque also will increase with the speed. The lesson? Lubricant with the correct viscosity for an application in the proper quantity will help succeed in keeping friction in check.

Grease has emerged as the preferred lubricant for rolling bearings, in part because grease is easy to apply, can be retained within a bearing’s housing and offers protective sealing capabilities. Oil represents another often-used alternative.

When grease lubrication is used and a bearing has just been filled— or refilled—with the recommended amount of grease, the bearing can show considerably higher frictional values during the first several hours or days of operation (depending on the speed) than may have been calculated originally. This is because the grease takes time to redistribute itself within the free space of the bearing and/or housing; meanwhile, it is churned and moved around. After this “running-in” period, however, the frictional moment will align with similar values as oil-lubricated bearings—and, in many cases, even lower values are possible.

Especially in high-speed and/or high-temperature applications, a major function of the lubricant is to remove heat, and circulating oil lubrication will be necessary. But, beware that excessive quantity of lubricant within a bearing’s boundary dimensions can increase friction and heat generation. This indicates that as much as possible, a proper flow rate of lubricant through the bearing should be obtained consistent with good lubricant film formation and heat removal.

Final footnote
In fighting friction, users can turn to these and other strategies for all the associated benefits. Regardless of the equipment applications, be they electric motors, fans, compressors, pumps, gearboxes or others, users should likewise consider turning to an experienced bearings manufacturer to help factor friction out of service. UM

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November 1, 2008
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Utilities Manager: How Healthy (Or Unhealthy) Is Your Network Power?

Network power—without power—would leave
you without a network. It’s a necessity, not unlike basic electricity needed to power your home or fuel to power your vehicle. But most companies don’t think about what goes into making a network run once it actually does.

In a standard, central offi ce power plant, there could be multiple power rooms, each containing rectifi ers, distribution bays, controllers and battery strings. What happens when one or more units malfunction due to over-utilization or neglect?

In an industrial environment, operational integrity is imperative. Businesses should consider the cost of an outage—downtime, lost productivity and the customer impact—as well as potential safety hazards. It is important not to have a false sense of security and later fi nd an outage could have been prevented by properly safeguarding your network. How acceptable is the loss of your network power for any period of time?

A fountain of youth for power equipment?
As part of comprehensive service performed by an expert, routine maintenance can be invaluable to businesses that depend on revenue generation from the reliability of power systems. That’s because alarming, plant capacity, overloaded breakers or fuses and overloaded AC panels can have a direct impact on network reliability. While not a magical solution, power plant maintenance can extend the life of network equipment, reducing the need for premature replacements—and therefore, reducing the overall cost of powering the network.

Evaluations, maintenance and adjustments should be part of any maintenance program. When performed by an experienced technician, potential problems can be caught before they do serious damage to the power equipment. Thermal scanning can be used to help identify overheating problems, such as overloaded busbars, undersized cables or loose connections.

Power plant capacity and irregularities also should be checked. For example, you should check the load against the capability and verify isolated ground planes and ground windows for contamination.

Always verify physical characteristics, operating capabilities and functionality when checking equipment, and be sure to compare installed equipment capacities with existing demands. Table I shows what elements should be maintained for batteries, power plants and DC Power Boards.

 

What happens when good systems go bad?
When systems are not properly maintained, results can range from simple, short-term outages, to explosions—like the battery room explosion in the opening photo—and expensive damages. Typical issues that can affect operations and reliability are loose or damaged connectors, defective circuit breakers, battery leakage, low-battery levels, improper ventilation, and wiring errors. These all can be detected during routine maintenance—which includes thermal scanning and calibration of power plant connections.

In the event of a commercial AC failure, diesel generators, fuel cells and UPS systems are designed to provide temporary AC power, allowing time for commercial AC to be restored. Regularly performed maintenance services with these back-up power systems ensures they are ready to engage should commercial AC power fail. Fuel is checked, visual inspections performed and systems are started to make sure they are in top running condition.

Similarly, in the event of a DC power plant failure, batteries provide instantaneous temporary DC power, allowing time for repairs to the power plant. Batteries are subject to numerous failures such as deteriorated power capacity, swelling, cracking, leaking, corrosion and releasing explosive gases. If the room in which the batteries are housed is not properly ventilated, the batteries overheat, the alarm fails and explosions occur.

Regularly performed maintenance services, such as taking critical battery output measurements, verifying battery connections and conducting visual inspections, can circumvent these types of failures by identifying problems well in advance of them becoming serviceaffecting events.

Low electrolyte and water levels reduce battery life and reliability. Loose and corroded connections can sometimes lead to serious overheating-related problems. A periodic maintenance program that includes thermal imaging services will quickly identify overheated connections that can easily be fi xed before a more serious event occurs.

What’s next?
The fi rst step for power plant operators to take is to identify a service provider that is willing to work closely with them in providing scheduled, preventive maintenance services. Using qualifi ed engineers and technicians is critical to help minimize the risk of back-up equipment failure in the event of power interruptions. Documented, extensive fi eld experience is a good indicator that a service provider understands your needs and can dispatch qualifi ed personnel to your site.

The service provider’s initial goal should be to help outline the entire package of required preventive maintenance activities, recommend a preventive schedule or multiple schedules of necessary services and provide complete documentation of findings and further recommendations each visit.

In order for them to deliver this type of comprehensive plan, the service provider must completely understand your current and future power demands and how the equipment you currently have will accommodate those demands. Your service provider also should be able to evaluate the working capability of your existing equipment with any new equipment you may need now or in the future.

Keep in mind that a service provider with multiple geographical or regional sites means that technicians are never too far away from your site(s)—and are ready and able to deploy for any emergency affecting your power service.

Is that bomb ticking?
Can you afford for your systems to go down in a crisis? And, how well do your competitors maintain their power equipment?

Power systems often are taken for granted until there is a loss of power and subsequent service is lost to valuable customers. Failures can happen at any time, with sometimes devastating results. Early detection can identify small problems before they become major repair costs. Take the next step. Don’t wait for that “bomb” to go off. Start your preventive maintenance today.

Brad Loy is regional installation manager for Lineage Power. During his more than 10 years working in power installation services, he has been involved with just about every conceivable iteration of power installation challenges there is. Telephone: (972) 284-2000.

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August 1, 2008
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Utilities Manager: Big Money Talks-Life-Cycle Costing & Energy Costs

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William C. Livoti, Baldor Electric Company

Life-cycle costing (LCC) is an often-used term in the pump industry, but one that rarely is implemented at the end-user level. Industry continues to use the same design criteria and specifications that have been in place for years—specifically, over-sizing of pumps, motors and valves. Energy costs won’t allow us to continue down this expensive path. LCC will become the rule rather than the exception around companies that want to remain profitable—or in business.

Interestingly, LCC is one of the most effective tools you can use to justify—and convince management to pursue—energy savings projects. Sometimes called Total Cost of Ownership (TCO), this methodology takes into account the following items when evaluating equipment and/or projects:

 

 

  • Purchase costs
  • Installation & commissioning costs
  • Energy costs
  • Other operating costs
  • Maintenance costs
  • Downtime costs
  • Decommissioning costs
  • Environmental costs

(More information on conducting LCC analyses is available online through any number of Websites. For example, to calculate the LCC of a pump, visit www.pumpsystemsmatter.org)

On the other hand, you can’t get your arms around LCC without fully understanding your utility costs— and you can’t measure them unless you know how to calculate your true cost of energy.

A typical U.S. industrial electric bill will include the following information required to calculate an operation’s true cost of energy:

  • Electric Usage History—Allows you to compare your electric usage over the past 13 months.
  • Power Factor Adjustment—A “billing adjustment’ that applies if the power factor for the metered service falls below 85% (or predetermined percentage) during the billing period. There is typically a large penalty for power factor deviation.
  • Usage Information—Includes the meter number for the point of delivery (POD), meter readings, days in billing period and total kWh usage.
  • Demand Information—Includes actual peak kW demand, on-peak and off peak demand and peak reactive power (kVAR).
  • Additional Facilities Charges—Indicates charges for additional facilities or non–metered services for specific account.

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The following equation can be used to calculate most any U.S. industrial electric bill:

Incorporate this equation in your LCC analysis. Don’t forget to take into account non-energy benefits:

  • Increased productivity
  • Reduced costs of environmental compliance
  • Reduced production costs
  • Reduced waste disposal costs
  • Improved product quality
  • Improved capacity utilization
  • Improved reliability
  • Improved worker safety

Capturing the benefits
You can learn a lot through an LCC analysis (and the analysis of your true cost of energy). Use it for the good of your operations. Learn and speak the language of management. Appeal to management’s profit motive. Relate savings to the plant’s bottom line. Whatever you do, remember that big money really talks!

Bill Livoti, our new Utilities Manager columnist, is senior principal engineer for Power Generation and Fluid Handling with Baldor Electric Company. He also is vice chair of the Pump Systems Matter initiative. E-mail: wclivoti@baldor.com

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August 1, 2008
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Utilities Manager: Spray Optimization Strategies

Using less compressed air, electricity and water in your drying and spraying operations can lead to significant savings. The right approach and the right device for the application are critical.

Systems that dry, clean, cool, coat and lubricate are easy to overlook as long as they seem to be providing the expected performance. That’s because the components in these systems are perceived to be quite simple. After all, if air is coming out holes in pipes and nozzles are spraying, everything is working properly, right? Wrong! Optimizing these operations can save tens or even hundreds of thousands of dollars annually by dramatically reducing compressed air, electricity and water consumption.

Let’s take a look at two strategies that are relatively easy to implement, eliminate unnecessary profit leaks and improve product and process quality.

Strategy 1: Slash or eliminate compressed air consumption
Most plants use compressed air to dry, cool or move parts. Typically, open pipes or pipes with drilled holes or slits are used. While this approach accomplishes the desired task, compressed air consumption is excessive when compared with alternate approaches. In fact, using air nozzles, air amplifiers or air knives instead of open pipes can reduce air consumption by as much as 92%. In some operations, the use of compressed air can be eliminated completely by using an air knife package powered by a regenerative blower. (An overview of the options and estimated reductions in air consumption is shown in Table I. Refer to Table II for specific cost savings.)

Air nozzles and air knife packages offer benefits in addition to reducing or eliminating the use of compressed air, including:

  • Perceived noise reductions from 28 to 60% with air nozzles; additional reductions achieved with air knife packages;
  • Improved worker safety;
  • More precise, repeatable drying and blow-off.

0808_um_spray_img11Air nozzles: versatile, efficient and suitable for many operations…
Air nozzles convert a low-pressure volume of compressed air into a targeted, high-velocity, concentrated air stream, flat fan or curtain of high-impact air. They come in a variety of types, capacities, sizes and materials. In addition, air nozzles can be used with CO2, nitrogen, steam or other compatible gases for special heating and cooling applications.

Air amplifiers: increased intensity and efficiency…
A variable air amplifier is another option when using compressed air. Air amplifiers produce a constant, highvelocity air stream for spot drying, blow-off, exhaust and robotic applications. Efficiency is maximized because additional free air is pulled through the unit along with the compressed air. Air amplifiers deliver higher volumes of air and operate at higher pressures than air nozzles for fast drying and blow-off.

Low-flow air knives: maximum efficiency in small areas…
Low-flow air knives deliver a high velocity, uniform air flow across the entire length of the knife. Drying and blow-off are fast and efficient and minimal air is used.

Designed for small areas, low-flow air knives are typically mounted close to the target. Maximum knife length (or combined length of all knives) is limited to less than 2′ (61 cm). Applications that only require one or two air knives can experience significant operating cost reductions by using low-flow models.

Some drying and blow-off operations are well suited to using regenerative blowers and air knives. Using blower air to power an air knife eliminates the need for compressed air and can result in substantial savings—including a reduction in operating costs by 95% or more. Air knife/ regenerative blower packages are rugged/reliable and require infrequent, minimal maintenance. They are ideal for applications that require:

  • High air velocity;
  • Oil-free operation;
  • Large application areas—more than 2′ (61 cm);
  • Heated air.

How much can you save?
Any plant with a drying, cooling or blow-off operation can likely experience savings. Table II provides estimated savings for a single operation.

If you currently are using open pipes, reductions in compressed air consumption are possible—and will quickly offset the cost of any new equipment. If you’re already using air nozzles, evaluating alternatives such as variable air amplifiers, low-flow air knives or air knife/blower packages is a good idea to see if further savings can be realized.

Strategy 2: Eliminate water waste by optimizing spray operations
Spray nozzles are precision-engineered components designed to deliver very specific performance. And, like all technology, newer, more efficient versions are introduced on a regular basis. Routinely monitoring the nozzles you use and exploring changes in the way you spray can lead to significant reductions in water consumption.

Nozzle wear = wasted water…
Using worn spray nozzles can be extremely wasteful—often going undetected, especially in the early stages, where the signs of wear aren’t readily visible. Monitoring nozzles closely and taking the appropriate action can save thousands of gallons (liters) of water per day.

As nozzles wear, their orifices become larger and, at any given pressure, the flow rate will increase. Nozzles that spray over capacity are not only wasting water. Electricity costs will rise due to excess pump operation, chemical consumption will increase and wastewater disposal costs will escalate as well. As shown in Table III, even slight nozzle wear can be extremely wasteful.

Some signs of nozzle wear may be visible. As drop size increases, spray patterns may change or become distorted. If the wear is due to erosion or corrosion, a quick look at the nozzles will reveal the problem.

What to do about nozzle wear…

  • Replace nozzles on a regular schedule. Many processors elect to changeout spray nozzles annually. Depending on the number and type of spray operations, the cost of replacement nozzles can be far less than the cost of wasted water even if the nozzles are only 15 to 20% worn.
  • Evaluate nozzle material. Changing nozzle material may minimize wear and waste. Nozzles made from harder materials generally provide longer wear life. In addition to standard materials such as brass, steel, cast iron, various stainless steels, hardened stainless steels, many plastics and various carbides, spray nozzles can also be supplied in other materials upon special request. Materials that offer better corrosion resistance also are available. The rate of chemical corrosion on specific nozzle materials, however, is dependent on the corrosive properties of the liquid being sprayed, its percent concentration and temperature, as well as the corrosion resistance of the nozzle material to the specific chemical.
  • Explore reducing spray pressure. Although it is not always possible, decreasing pressure, which will slow the liquid velocity through the orifice, may help reduce the orifice wear/corrosion rate.
  • Add line strainers or change to nozzles with built-in strainers. In many applications, orifice deterioration and clogging is caused by solid dirt particles in the sprayed liquid. This is particularly common in systems using continuous spray water recirculation. Strainers, or nozzles with built-in strainers, can trap larger particles and prevent debris from entering the nozzle orifice or vane to significantly reduce wear.

Consult the accompanying “Spray Nozzle Checklist” sidebar at the end of this article for more pointers.

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Consider changing the way you spray…
You may be able to conserve vast amounts of water by making some simple changes to your spray operations. As a starting point, you may want to consider taking these steps.

  • Use nozzles that precisely spray the target. Overspray is not only wasteful, it can cause excess maintenance and impede production.
  • Add handheld spray guns to open hoses to ensure water is “on” only when needed.
  • As spray nozzles wear out, replace with water-saving models.
  • Equip all hoses with spring-loaded shutoff nozzles and make sure they aren’t removed.
  • Instruct workers to use hoses—equipped with spray guns—sparingly, and only when necessary.
  • Change shower heads to smaller nozzles.
  • Install high-pressure, low-volume nozzles on spray washers.
  • Use fogging nozzles to cool products.

Consult the experts to maximize benefits
An on-site evaluation of your drying, cleaning, cooling, coating and lubrication operations from your spray nozzle manufacturer is the most expedient and thorough way to identify possible improvements and quantify the resulting savings. Leading manufacturers don’t charge for this service and will conduct a comprehensive audit of all your operations in a single visit and provide a written summary report that includes recommended changes. It’s a risk-free way to learn more about how to lower energy and water consumption and a valuable service for every processor with spray operations.

Spray Nozzle Checklist

Flow Rate – Each Nozzle
Centrifugal Pumps: Monitor fl ow meter readings to detect increases. Or collect and measure the spray from the nozzle for a given period of time at a specifi c pressure. Then compare these readings to the fl ow rates listed in the manufacturer’s catalog or compare them to fl ow rate readings from new, unused nozzles.

Positive Displacement Pumps: Monitor the liquid line pressure for decreases; the fl ow rate will remain constant.

Spray Pressure – In Nozzle Manifold
Centrifugal Pumps: Monitor for increases in liquid volume sprayed. (Spraying pressure likely to remain the same.)

Positive Displacement Pumps: Monitor pressure gauge for decreases in pressure and reduction in impact on sprayed surfaces. (Liquid volume sprayed likely to remain the same.) Also, monitor for increases in pressure due to clogged nozzles. Visually inspect for changes in spray coverage.

Drop Size
Examine application results for changes. Drop size increases cannot be visually detected in most applications. An increase in fl ow rate or a decrease in spraying pressure will impact drop size.

Spray Pattern
Visually inspect each nozzle for changes in the uniformity of the pattern. Check spray angle with protractor. Measure width of spray pattern on sprayed surface.

Jon Barber is a director at Spraying Systems Co., based in Wheaton, IL. The company, which is celebrating its 70th anniversary, offers nozzles in thousands of sizes, hundreds of configurations and dozens of materials. Designed to improve efficiency, these products range from quick-change units that require no tools for installation to anti-bearding nozzles that increase throughput. For more information, contact Barber directly. Telephone: (630) 665-5000; e-mail: jon.barber@spray.com

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August 1, 2008
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Utilities Manager: Color Your Lube Program Green

0808_color_img1Adopting “green practices” as a catalyst for change around your operations doesn’t have to be painful or expensive, but it does require open minds.

Things are changing around our plants and facilities these days. The exponential rise in energy rates coupled with a global shift toward protecting the planet and its resources has forced company after company to seek “greener” alternatives to their operating practices across the board. Growing out of the increased awareness and understanding of the challenges we face has been a real open-mindedness—even an eagerness—in implementing programs that benefit BOTH environmental and business goals.

If your company is going “green,” there is no better place to begin or enhance your efforts than by updating—or “greening”—your lubrication management program. It’s a simple rationale. Equipment wear is caused by friction. Choosing the wrong lubricant, applying a lubricant incorrectly and/or at the wrong time and allowing a lubricant to become contaminated are things that lead to excessive friction. That, in turn, manifests into higher energy requirements to overcome the increase in friction and abrasion that causes seal damage, which can result in environmentally-unfriendly leaks and spills.

Taking a “greener” approach in your lubrication efforts will result in signifi- cant energy-cost reduction, reduced lubricant inventories, reduced lubricant consumption, reduced lubricant spills, cleaner equipment, reclamation and reuse of existing lubricants, responsible disposal of old lubricants and substantial increases in equipment reliability, availability and throughput—for little or no capital outlay.

Check out the following seven tactics. Employing one, more, or preferably all of them will go a long way in coloring your lubrication program “green.”

0808_color_img2Tactic #1: Lubricant Consolidation
Many companies will carry an inventory of 20 or more lubricants throughout their plant, often stored in half-open containers exposed to atmospheric contamination and in danger of being spilled. Remember, TODAY’s lubricants often are capable of out-performing many of YESTERDAY’s lubricants—products you have continued to purchase, stock and use over the past decades. Consolidation programs easily can reduce lubricant inventories by up to 75% or more, depending on the industry, lowering and purchase carry costs and simplifying lubricant application. Most importantly, consolidation forces you to inventory ALL of your lubricants in the plant, and list every storage location.

Consult with your lubricant suppliers about performing a lubricant consolidation exercise. Such a program typically is offered at little or no cost, in exchange for a blanket order that also can work in your favor by fixing lubricant costs for a set period.

0808_color_img2Tactic #2: Contamination Control
Contamination is an enemy of both wear surfaces and lubricants. Fortunately, it can be controlled with a little effort and awareness. Contamination issues are largely caused by poor storage, handling and application practices. Fine-tolerance bearing surfaces and radial lip seals do not take kindly to lubricants carrying abrasive bodies to the wear surface. Why then, do some technicians/organizations continually grease nipples without first cleaning the grease gun and nipple, leave off reservoir lids and breather caps in hydraulic systems, leave off lubricant container lids, store barrels of lubricants outside and exposed to extremes in weather where they rust and collect water, and use non-dedicated and dirty lubricant transfer devices?

Review how you perform in keeping contaminants from entering your lubrication systems. Then, consider investing in better housekeeping practices and some of the many new dedicated transfer systems offered by your local industrial supplier.

0808_color_img2Tactic #3: Filtration
Poor machine filter management can manifest as reduced lubricant flow, and cause the bypass of deadly wear contaminants to your bearing surfaces. Ensure that filter replacement is a high priority in your preventive maintenance program.

In an effort to conserve and reuse lubricants, an external pump/filtration cart can be used to clean your large reservoir lubricants and ready them for reuse. This will save on lubricant, change-out and disposal costs. Contact your local lubrication hardware or filter supplier for details on this type of easy-to-use system.

0808_color_img2Tactic #4: Spill Containment
Oil spills are never easy to deal with. Prevention can result in a lot less effort should one occur. When storing lubricants ensure that all full or partially full containers are kept in an area protected by an impermeable berm that contains a spill in a localized area. The containment system can be a steel box tray, concrete berm system or one of the many plastic containment systems sold by your local industrial supplier. Don’t forget to keep a spill management kit on hand—just in case!

0808_color_img2Tactic #5: Engineered Lubricant Delivery
Both under- and over-lubrication will cause a significant spike in energy requirements—one to overcome the metal-to-metal collision and the other to overcome fluid friction. Tuning your lubricant delivery can result in energy savings as high as 20%. Invest in a Lubrication Operation Effectiveness Review (LOER). Conducted by an accredited lubrication consultant, an LOER will provide recommendations on how to improve your current approach to delivering the right lubricant, in the right amount, in the right place, at the right time, whether from a grease gun or fully-automated system.

0808_color_img2Tactic #6: Lubricant Disposal Program
In countless communities, local legislation is forcing companies to own their waste and put in place waste disposal plans or programs. Many companies operating under a consolidated program have been able to set up recycling programs wherein all their old reservoir lubricants are taken back, cleaned, reconstituted with additives and resold back to them as recycled oil—at savings of up to 25% of virgin oil. These programs save disposal costs and the environment, as well as reduce the costs to purchase new oil. Collecting oil by type makes it easier for the disposal company and reduces the disposal costs charged to you. Learn what program(s) your disposal company offers, then start capturing your own savings.

0808_color_img2Tactic #7: Lubrication Training
A little basic lubrication training can ratchet up your team’s understanding and enhance your program significantly. While lubrication may appear to be very intuitive in nature, it is perhaps the least understood area of maintenance—and still responsible for up to 70% of all mechanical failures. Investing in a basic lubrication training course will facilitate your program immensely.

Now that you have these seven tactics down, get out your paintbrush. You’ll soon be on your way to successfully coloring your lubrication program GREEN.

Contributing Editor Ken Bannister is the author of the bestselling book, Lubrication for Industry (Industrial Press), and the author of the new lubrication section of the 28th edition of Machinery’s Handbook (Industrial Press). He conducts lubrication effectiveness reviews and training programs throughout industry. E-mail: kbannnister@ engtechindustries.com

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218

6:00 am
August 1, 2008
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Utilities Manager: Utilities Manager

0808_heat_img11

In the quest for more energy-efficient operations, every little bit helps.

As companies demand more energy efficiency from their systems, valve heating could be a real consideration. One area where energy losses can occur is on long pipe runs and their intersections such as T-fittings and valves. On an individual basis, energy losses around valves might seem minuscule. But, when an application has multiple valves in a system, such losses can quickly add up. Since it is a given that some losses will occur in heating systems, it makes sense to use heaters with insulation to maintain temperature.

Problem overview
Valve heating is critical to many processes. Markets and applications such as petrochemical, freeze protection, metal casting, pulp and paper processes and transportation are just a sampling of the many areas that have valve heating needs. Moreover, these markets seem to be without boundaries. For example, hundreds of feet below the earth’s surface, an arctic mining operation might utilize flow valves that must withstand up to 5000 pounds of pressure per square inch while operating at a constant temperature. On the other hand, an instrumentation valve, which is a key component in an aerospace application, must be able to handle extreme swings in temperature. These applications require quality heating devices to maintain temperature, thus reducing the chance of failure. The heat produced from the heaters may be necessary to reduce viscosity of the medium as it flows through the valve. If the heater fails, it can cause serious damage, halt the process or compromise safety. Additionally, agency requirements such as, UL®, CSA, CE, or RoHS might be necessary.

As varied as the industrial marketplace needing valves is, so too are the many valve geometries being utilized. While valve shapes and sizes—along with application requirements and pricing—are unique, the basic functions of valves are quite similar. In general a valve is a pass-through device regulating flow. It can be made of lightweight aluminum and incorporate a measurement device with an actuator for an oil pump line or be as simple as a polymer ball valve for an irrigation system.

Understanding process needs
It is best to take an application’s heating needs into account in the early stages of the system design phase. Too often, though, system heat is an afterthought and the design engineer or field technician has to scramble for a solution. Fortunately, there are many heater types to choose from when it comes to valve heating.

Heaters can be applied by wrapping them around the valve. They also can be integrated as part of the assembly at the time of the initial design. Choosing the appropriate heater for the valve is as important as choosing the appropriate valve for the application. Such a task means understanding the marketplace with respect to heater offering. There are several heating options that warrant a more in-depth review before selection.

Picking the correct solution
If placing heat close to the medium is important, a cast-in heater is an excellent option. Depending on the size of the valve, heaters such as FIREROD® cartridge, cable or WATROD tubular heating elements can be utilized by placing them in direct contact with the valve body or used in open air near the valve. In smaller geometries, when space is critical, cable or cartridge heaters are excellent options. If casting the heater as part of the valve is not an option, drilling holes and utilizing a cartridge insertion heater is another good option.

Opportunities exist in the aftermarket for heating valves. Creating a heated enclosure or “hotbox” around the valve and utilizing a tubular heating element, silicone rubber heater or small, finned strip heater are excellent supplemental heater options. The heater enclosure helps contain the heat while protecting the electrical connections from the elements of weather—and the use of insulation in the enclosure is a great energy saver. These heaters also are good choices when heating manifold valve assemblies.

In particular, some applications utilizing manifold valves might require easy-to-install, blanket-type heaters in direct contact with the part. Blanket heaters can be designed with holes and notches to accommodate the obstructions. These heaters offer the operator easy access to handles or instrumentation without significant disassembly. As a bonus— including energy-saving benefits—these heaters can be shipped from the factory with an insulation backing. This reduces field service time by not having to add additional insulation.

Some valve heating applications require good controllability as a result of temperature limitations of the medium. In addition, temperature sensitive parts such as O-rings must not exceed melting temperatures. Incorporating a sensor (such as a thermocouple or RTD) as part of the heater solution can save headaches down the road. These sensors work in concert with the control system and keep the heater from over-temping, and therefore prevent the system from overheating.

0808_heat_img3If the heater is designed on a new OEM application or becomes an aftermarket requirement, pre-formed silicone rubber heaters with ¼-inch insulation that act as portable ovens around valves can be used. This type of heater works well when used on snow making equipment. The machine continuously produces snow as long as the water lines and valves are protected from freezing. At a recommended maximum watt density of five watts per square inch, these heaters can safely reach 300 F (149 C). In some cases this heater can contain integral bimetal thermostats to maintain temperature. These heaters also have an optional removable blanket with snaps for quick assembly. The blanket holds in heat while holding the heater in place.

When higher watt densities are needed for higher temperatures or faster heat-up requirements, the cable heater is an excellent choice. Some cable heaters can handle 30 watts per square inch and easily reach 300-500 F (149- 260 C) in just minutes.

The real cost
Safety clearly is a top concern when heat is needed in any system. The following is an account of an actual situation wherein a refinery system failed because of the slow action of an emergency cut-off valve that compromised human safety and cost the company significantly.

An emergency shutdown procedure took place as a result of abnormally high system pressure. Consequently, the delayed operation of the pressure relief valve due to a viscosity rise of the liquid was the contributing cause of the failure. Due to the high pressure that took place, a leak occurred and ignited a fire.

The slow action of an automatic switching valve was the result of low temperatures and high humidity. The instrumentation required heat in and around the valve to function properly, and the dehumidification typically prevents problems with the condensed water. A viable solution for this type of problem would have been to utilize a molded silicone rubber heater with an integral sensor. In other words, the accident at this refinery could have been prevented if heat was applied to the cut-off valve, which would have kept the moisture from freezing around the valve assembly.

Bottom line
Multiple valve designs and heating solutions lead to versatility in the marketplace. The heat required in an application can get overlooked at times. It is up to the system designer to identify early on when the heat generated by the process is simply not enough and then determine the best heater solution for the particular application.

John Pape has worked for Watlow for 19 years. His current duties include account management, and pre- and post-sales support

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6:00 am
August 1, 2008
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Utilities Manager: Mobile Real-Time Inspection Of Combustion Processes

0808_whatshot_img1Lenox Instrument’s portable FireSight® Diagnostic System provides efficient, real-time, color inspection of combustion and process control in boilers, furnaces, kilns and incinerators. This entirely self-contained unit allows diagnostics, testing, monitoring and recording of several individual boiler or furnace functions operating at any level via any available 1?” (41.3 mm) opening. It consists of an air filtration and power system and 8″ CCD color monitor in a durable case with telescoping handle and wheels. The air-cooled furnace lens assembly is offered with either a 24″ or 36″ lens, in either direct or right-angle view configurations. An optional mini-digital video recorder with an LCD screen also is available. Capable of operating in temperatures up to 3000 F (1649 C), this system is well-suited for use in power plants, steel mills, paper mills, glass plants, cement kilns and incinerators. Its high-color image clarity is particularly valuable in helping speed light off, evaluate flame intensity and patterns, determine the status of igniters, view flame impingement, NOx emissions, CO and O2 imbalance, high unburned carbon (LOI), eyebrows, slag, clinker and ash build-up. Among its many features, the Light Volume Control, a Lenox exclusive, lets operators easily adjust the amount of light transmitted to the camera, eliminating the bloom common with other systems and ensuring a high-quality color image from initial light-off to maximum load.

Lenox Instrument Company
Trevose, PA

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