To resume our “The Rights of” blog post series which included The Rights of Precision Balancing and The Rights for Precision Shaft Alignment, I decided to give compressed air leak detection and repair a try with some basic rights when using PdM technologies like Airborne Ultrasound and Acoustic Imaging.


Here are my 14 rights to help you find those pesky and costly air leaks. Can you think of any others?

  • Right safety procedures before you start your survey.
  • Right leak management procedure to help you find-and-find leaks.

Download our Infographic Find-and-Fix Procedure to help environmental sustainability with reduced energy waste.

  • Right pre-survey check of compressed air system layout/drawings.
  • Right pre-survey gauge check (PSI)
  • Right pre-survey inspection of pipe location, valves and fittings.
  • Right leak detection instrument

Now days you can choose from an airborne ultrasound tool like our SDT ULTRAChecker all the way to an ultrasonic acoustic imaging camera like our new SDT Sonavu.

  • Right leak location before you tag it.
  • Right measured dBuV value in defect log.
  • Right LOTO procedures before you start repair.
  • Right leak location and severity report.
  • Right leak elimination.
  • Right re-measured dBuV value in work order.
  • Right estimate of the cost impact of leaks.
  • Right comprehensive reports to share your wins throughout your organization.


Download our SDT LEAKReporter App to help you document and quantify your energy savings $$$.

by Ana Maria Delgado, CRL

We previously discussed misaligned couplings and how to reduce failures when ultrasound and alignment meet in “Ultrasound and Alignment Meet at the Coupling to Reduce Failures.” In this follow-up blog, we will discuss how ultrasound and alignment come together to improve belt-driven performance.

Misalignment in belt-driven equipment is one of the leading causes of failures throughout the industry. It breaks down machines and often costs your company thousands upon thousands of dollars in repair expenses and unplanned downtime. Imagine if you could combine two technologies you may already be using to prevent some of these failures. Ultrasound and precision laser alignment will make your maintenance department ever more proactive than ever before.

Figure 1

Belts can be too loose, too tight, or be running on misaligned pulleys. Loose belts will slap and produce a noise similar to whiplash. Tight belts and misaligned belts will generate additional friction which will again be audible ultrasonically. Figure 1 is a sample time signal of slapping belts.

An easy way to detect and prevent failures is to add your belt driven machines to your ultrasound routes. It will require a few extra measurements on each route and some trending. However, the benefits will far outweigh the costs. By being able to tell when a belt system needs to be aligned and properly tensioned before it breaks down, we can be more proactive and less reactive.


Once the imminent failure is being detected, we can address it with a realignment of the belt drive unit using our Easy-Laser XT190 pulley alignment system. It is easy to use and it will provide the user with a PDF report for documentation and accountability.


This blog was inspired by Uptime Magazine’s article, “There’s Something in the Air”, July 2009, pp. 48-53, written by Thomas J Murphy with SDT Ultrasound Solutions.

Download our 5-Step Sheave Pulley Alignment Procedure which provides a simple and effective procedure for sheave pulley alignment of belt-driven equipment. 

by Diana Pereda

Misalignment in rotating equipment is one of the leading causes of failures throughout the industry. It breaks down machines and often costs your company thousands upon thousands of dollars in repair expenses and unplanned downtime. Imagine if you could combine two technologies you may already be using to prevent some of these failures. Ultrasound testing and precision laser alignment will make your maintenance department more proactive than ever before. For example, we all know couplings can be misaligned, and couplings can be loose. Infrared training tells us that a misaligned coupling generates heat. This heat is generated by the periodic friction caused by the coupling being squeezed with each revolution. Remember, friction we can hear. Therefore, a misaligned coupling will generate a periodic ultrasound signal like the one shown in Figure 1.

Figure 1

If you are already using ultrasound and laser shaft alignment, you are already there.  All you have to do is add the coupling data point to your current ultrasound routes. This simple step combined with some trending will tell you when you need to check and correct the misalignment on the pieces of equipment along the route. Furthermore, a loose coupling will generate an ultrasound signal caused by the fretting of the coupling halves rattling. This fretting will be harsher and less periodic in nature than misalignment (see Figure 2).

Figure 2

Once the imminent failure is being detected, we can address it with a realignment of the machines using an Easy-Laser laser alignment system like the XT770. It is easy to use and it will provide the user with a detailed PDF alignment report for documentation and accountability.

Ultrasound Coupling Inspection with Flexible Sensor

For more information on Ultrasound coupling, refer back to our blog, “Airborne Ultrasound Keeps Flexible Couplings Reliable” as shown above featuring our SDT340 Ultrasound Solution.


This blog was inspired by Uptime Magazine’s article, “There’s Something in the Air”, July 2009, pp. 48-53, written by Thomas J Murphy with SDT Ultrasound Solutions.

Download our 5-Step Shaft Alignment Procedure which provides a simple and effective procedure for shaft alignment of rotating equipment.

As an additional resource, we recommend watching, “Utilizing Ultrasound for Reliable Coupling” a presentation by Robert Dent with SDT Ultrasound Solutions

by Diana Pereda

Ultrasound for coupling inspection?  What?  Yes, ultrasound technology has many pillars for asset management.  The technology is amazing and can be used in a variety of different not so obvious applications.

Fig 1 – Worn out grid coupling


Types of couplings you can inspect with Ultrasound and how

There are many different types of couplings used in the industry for rotating equipment. These can range from short-flex, spacer type, to even Cardan shaft. Some require lubrication and others do not. One proven method to assess coupling conditions is to use an ultrasound analyzer with dynamic capabilities and a flexible airborne sensor and collect data for approximately 5 seconds per coupling. From there, a user can analyze the data using the Ultranalysis2 software to view the dynamic data (time waveform and spectrum).

Some machines may be running misaligned; therefore, the couplings may be loose.  If we had a thermography camera, we could take an image of the heat signature which might show the periodic friction (squeezing of the coupling as it goes through each revolution).  However, more often than not this will not be possible as all equipment must have coupling guards present during operation. Therefore, a flexible ultrasound sensor will be able to pick up that friction being generated by the coupling.

If you are currently not using an ultrasound system to check your couplings, it’s time to start!

Lack of lubrication and worn out grid coupling example:

Time Waveform for Fig 1
Impacts at running speed with harmonics for Fig 1


by Diana Pereda

Ultrasound Measurement Application Mining 870x460

The many applications of Ultrasound, as diverse as they are, rarely get used to their fullest capacity.  The Mining Industry poses many challenges in condition monitoring due to various machine types, speeds, and access.

Below are 10 of some of the prime applications for Ultrasound:

  1. Air Compressors and Blowers designed to supply air on demand often run inefficiently due to leaks. Use Ultrasound and SDT Leak Reporter to locate, document, and report leaks. Download our Leak Management: Find-and-Fix Leak Procedure for an effective procedure to survey your systems and detect leaks.
  2. Fugitive dust is an environmental problem and is often contained in the mining industry with the use of Baghouse Dust Collectors. The dust collectors require compressed air and diaphragms to purge the baghouse “socks.” A common failure mode for these socks is the ingress of moisture. One source of moisture ingress in compressed air lines are leaks.  Another area to utilize ultrasound is for the diaphragms themselves.  Use ultrasound to sweep across the diaphragm header to pinpoint a ruptured diaphragm.  Typically these are only found after the differential psi indicates plugged bags and requires a physical inspection.  Be proactive and efficient with ultrasound.
  3. Combustion Chambers in dryers that utilize natural gas are another area that can be prone to leaks. Check all the valves, and flanged connections periodically to identify a potential leak.
  4. Dryers and Kilns run at very slow speeds. Slow speed condition monitoring can be quite difficult using Vibration techniques. The slower the speed, the longer the sampling time and lower the amplitudes.  Ultrasound can be utilized to quickly assess the bearing health and to ensure proper lubrication.  Although the speed can be quite low, the frequencies of sound generated in rolling element bearings are ultrasonic due to friction of an inadequate lubrication film, or from the presence of subsurface asperities in the early bearing failure stages.
  5. High Voltage Electricity with potential for arc flash is used both above and below ground. Ultrasound can be used to safely locate arcing, tracking, and corona, without the need to open any panels. Use ultrasound underground on the 4160 V terminal connections, or on your miner Nips to ensure a good tight fit free of discharge.  Scan the overhead electrical cables while driving down the conveyor lines and listen for electrical discharge.
  6. Mines are loaded with long Belt Conveyors both on the surface and underground. Ultrasound is great for monitoring the head pulleys, tail pulleys, take-up pulleys, and for noisy trough idler rollers and return rollers.  We all know the havoc a seized idler can wreak on the belt and belt splices.
  7. The use of grid couplings is quite common on Fans and Crushers. Grid couplings require periodic lubrication and inspection for wear.  This requires shutting down the equipment, performing lock out tag out, and disassembly.  Use ultrasound and a flex wand to listen under and around the guard of a dryer for a loose fit coupling.
  8. Hydraulic Systems are used in many applications such as compactors, crushers, and booms on continuous miners. Use the contact RS2 probe to look for faulty psi relief valve and check valves.
  9. Mines typically have many designated Oxygen-Acetylene Bottle Storage areas. Acetylene is very unstable and can be quite explosive at atmospheric pressures.  Use ultrasound to check for leaks and help lower the risk of an explosion.
  10. Hoists are used to bring ore up from underground. The bearings of the crown sheaves and drums can be quite difficult if not impossible to monitor with vibration analysis as the RPM of the equipment rarely stays constant long enough for good reading.  With ultrasound, we need only about 15-20 revolutions for quality reading.

Today’s blog is inspired by a LinkedIn post written by our partners at SDT Ultrasound Solutions.

by Diana Pereda

Ultrasound Coupling Inspection with Flexible Sensor

Simon is a condition monitoring specialist from a local oil refinery. He contacted SDT for advice on predicting flexible coupling failures. Currently, they perform condition monitoring on their pumps and motors using vibration analysis.  They identified most bearing failures in time but could not detect coupling defects; there was no safe place to mount a contact sensor. Several unexpected failures caused shaft damage and unplanned downtime.

Within the facility they identified 58 pump systems considered “A Critical”, meaning if they go down, the plant goes down. I suggested ultrasound as a fast, safe, and affordable coupling monitoring solution. The model I recommended not only provided Simon with a means to observe couplings, it also measures vibration, eliminating the need to carry two data collectors.

Vibration analysis performs poorly on flexible couplings for two reasons. First, there is no suitable contact point for an accelerometer. Second, the primary defect symptoms of a defective coupling are friction and impacting. These are best detected with ultrasound. An airborne sensor placed near the coupling quickly detects problems. If necessary, Simon can capture a dynamic measurement and trend the defect as it worsens. The SDT270DU gives Simon two choices. He can periodically check for defects (Good) or Simon can integrate all 58 couplings into his established bearing routes (Best).

I explained to Simon how several clients already trend couplings using the Flexible Wand. The SDT270 collects a STATIC ultrasound measurement that gives four indicators of condition. The first two – Overall RMS and Max RMS – indicate the level of friction produced by the defect. When these indicators rise, maintenance may consider corrective alignment during a planned shutdown. The second two – Peak and Crest Factor – identify the emergence of impacting. Together, all four indicators establish a lifecycle trend for each coupling.

Once impacting appears, the Peak indicator increases in step with Overall RMS. Since Crest Factor (CF) is a ratio between RMS and Peak, a rising CF indicates that the window for simple maintenance has narrowed. At this stage inspectors collect a DYNAMIC measurement. The DYNAMIC measurement gives a visual representation of friction and impacting severity using the time view. For both STATIC and DYNAMIC measurements, it’s important to define the signal acquisition time.

User defined signal acquisition time, available exclusively on SDT instruments, is a luxury that lends ultrasound technicians the highest level of precision. Without the ability to set the sample time, inspectors must guess when to pull the measurement trigger, and then question the validity of their data. Simon explained that all 58 pumps turn at speeds above 1800 RPM. Accordingly, he should set his SDT270’s signal acquisition time to between one and three seconds. This guarantees data samples over 30-90 shaft revolutions.

Shaft couplings are guarded for safety and ultrasound inspectors working around rotating equipment must follow company safety policies. SDT designs safety considerations into their solutions. The Flexible Wand’s 10mm diameter sensor allows access to couplings without the need to remove safety guards. The 21” long sensor sports a comfortable, ergonomic grip that keeps inspector’s hands at a safe distance.

Simon seemed convinced but wanted to #HearMore. Since this solution was already working well at a nearby paper mill, I introduced Simon to the plant manager, Sunil, and invited them both to lunch. Sunil and Simon connected on many common reliability issues that afternoon. He confirmed the affordability of this solution based on coupling failures alone but went on to explain how their mill was rolling out ultrasound for acoustic lubrication, steam trap monitoring, electrical inspection, and air leak management. Simon and Sunil continued their conversation well into the afternoon. They agreed that ultrasound, with its 8 applications pillars for reliability, represented a fast, safe, and affordable technology with the potential to revolutionize reliability culture. I sat back, happily watching two passionate specialists strategize about reliability culture. I love my job.


by Diana Pereda

There are four condition indicators RMS, Max RMS, PEAK, and Crest Factor. Easy to explain and use, it can give you an overview of an assets health with just one reading.
Ultrasound Four Condition Indicators
Let’s go over them in more detail:
  1. RMS – use it to indicate trends in friction levels (lubrication, stage 1&2 bearing failure)
  2. Max RMS – use it to indicate ultrasound signal stability (steam traps, chain drives, flexible couplings, linear bearings)
  3. PEAK – use it to indicate impacting (shift from stage 2 to stage 3 bearing failure, fatigue, gear mesh, broken gear teeth)
  4. Crest Factor – use it to correlate the relationship between friction and impacting on any asset (perfect for VFDs!!)
Here are some ways in which these condition indicators can be applied. They can be combined as follows:

Friction & Rubbing:

  • Gas & Valve Leak – RMS
  • Lubrication – RMS
  • Steam Trap – RMS & Max RMS (+Peak for flash steam)


  • Bearing, Gears – Peak & RMS (+Crest Factor)


  • Cavitation – Peak


Check out our SDT 200, 270, and 340 featuring the four condition indicators to detect, trend and analyze ultrasound and vibration.

by Diana Pereda


Compressed air is one of the three highest cost utilities in use at your plant. It is also one of the least maintained in terms of system leaks. Leaks are expensive and wasteful, but most often ignored. Leaks may occur anywhere in your compressed air system. Here’s our list of top ten most common leaks:

  1. Connections on air supply lines (pipes)
  2. Quick couplers
  3. Filters
  4. Pneumatic cylinders
  5. Pressure regulators
  6. Air dryers
  7. Isolation valves
  8. Control valves
  9. Automatic drain traps
  10. Air separators

Finding and fixing these leaks is an easy way to reduce energy costs, but finding them is not easy because of background noise. A good quality ultrasonic detector can hear turbulence despite the ambient noise of the factory floor.

Download our LEAK SURVEYORS HANDBOOK and learn how to reduce or eliminate wasted compressed air with ultrasound through effective leak detection and repair.

Source: Ultrasound Leak Surveyor’s Handbook by SDT International.

by Diana Pereda



Condition monitoring helps manage over-lubrication.

Ultrasound is a guide to precision grease replenishment in motor bearings. It is also known for its versatility for leak detection, valve assessment and electrical fault detection.

Acoustic lubrication is an integral component of ultrasound programs. Fewer than 95 percent of all roller bearings reach their full engineered life span, and lubrication is the culprit in most cases. In fact, poor lubrication practices account for as much as 40 percent of all premature bearing failures. Yet, when ultrasound is used to assess lubrication needs and schedule grease replenishment intervals, that number drops below 10 percent. What would 30 percent fewer bearing related failures mean for an organization? Download our 5-STEP Acoustic Lubrication Procedure – An effective lubrication procedure to grease bearings right

To understand the role precision lubrication plays in bearing life extension, it helps to understand basics of bearings, their lubrication mechanism and how ultrasound helps.

The insides of a bearing consist of four components. The inner and outer raceways form a path for the rolling elements to glide on a thin film of lubricant. A metal cage separates the rolling elements, keeping them evenly spaced to distribute the load and stop them from crashing into one another. These components move in concert producing frictional forces from rotational inertia, surface load, misalignment, imbalance and defects. Zero friction is impossible, but optimal levels of friction are achievable with correct installation techniques and proper amounts of lubricant. Download our Induction Heating Procedure – Bearing Mounting – A simple and safe procedure for proper bearing installation

Ultrasound works on the FIT principle—it responds well to defects that produce friction, impacting and turbulence (FIT). For motor bearings, two of these phenomena apply: friction and impacting. Ultrasound detects high-frequency signals produced when two surfaces slide together or come in contact with any force. Stage 1 bearing failures happen at the micro level. Because ultrasound ignores low-frequency audible signals, it forms the perfect companion for measuring, trending and analyzing defects despite high levels of noisy interference encountered on the factory floor.

Ultrasound detectors detect friction and impacting as acoustic energy from rolling friction and defect impulses. When lubricant levels are optimum, the energy created is at its lowest. As frictional forces increase, so does the acoustic energy. Ultrasound instruments measure friction and impacting as energy using the scaled value dBµV (decibels/microvolt). The results are presented as condition indicators, and there are four of them:

  • root mean square (RMS)—an indicator of friction
  • maxRMS—an indicator of stability
  • peak—an indicator of impacting
  • crest factor—which surmises the relationship between friction and impacts

Condition indicators are most responsible for transforming ultrasound technology from a simplistic, “point the gun and pull the trigger” gadget, to being recognized as analysis and trending technology. Condition indicators add validity to trending by going beyond the single decibel. If a user currently uses an ultrasonic gun that does not have condition indicators, they should question the data. Click here to read the entire article “Use Ultrasound to Optimize Grease Replenishment”


by Diana Pereda

We’ve all read about it: leak detection should be a top priority since leaks can account for up to 30 to 40% of consumed volume… So, why is this issue still on the table? Why is it difficult to change things in the field?

In industry, one of the most common applications for ultrasonic detectors is to search for leaks to achieve greater energy savings. For both service providers and maintenance engineers, the hardest task is not so much to localize the leaks, which is child’s play if you have the appropriate tool, but to generate a report of the problems found, organize the required repairs and communicate the resulting savings to management and others within the company. A company-wide cost reduction program will be efficient only if all stakeholders are involved. When the implementation of an efficient program aiming at minimizing the energy costs related to compressed air fails, it is not due to technology, which almost never fails, but to human factors. All surveyed companies that had initiated a leak detection program that did not last over the long term had something in common: a lack of communication.

The successful implementation of an energy-saving strategy relies on good communication between all stakeholders, directly or indirectly. What you need to do is involve five different persons or groups, each having a very specific role to play in this campaign. The first person is the Ultrasound Inspector: he/she knows the network and where to find the losses. The second person is the Purchasing Officer: he/she buys the equipment required to manage the program and possibly negotiates power supplies. The third person is the Maintenance Planner: he/she will schedule the repairs to be done after inspection of the network. The fourth group is the Maintenance Supervisor and Technician(s) who will repair the defects that have been localized. The fifth person involved is the most important one: he/she is the Executive Sponsor whose role is to motivate and drive the project and communicate the savings achieved to all concerned. By highlighting these savings within the company, he/she will make the project come alive with visible and measurable results.

It’s easy to say, but in reality takes a lot of time and organization. However, since the advent of smartphones, tablets and other connected devices in the maintenance world, you can now use free assistance tools available as iOS/Android applications to measure leak-induced costs and document them with pictures. These applications can also be used to assist the various stakeholders and monitor the different steps to complete the implemented program (e.g., LEAKReporter, LeakSurvey). These tools are now able to automatically assess the costs of the defects detected over an entire year. Communication between all departments affected, directly or indirectly, by the program is now simple and natural.

In 2018, we worked with a company located in the North of Manchester, England, which, for many years, has used measuring instruments to detect leaks. However, no energy savings have been observed nor measured. As a result, the team was experiencing a loss of motivation and had given up on its cost reduction strategy. Thus, our customer’s request was simple: give a new life to their projects. The first steps consisted in clearly redefining everyone’s role. The second step was to train the team in the use of newly available tools: leak detector and mobile applications. The third step was to set up a “think tank” inviting all stakeholders to reflect on the best approach to adopt to manage and organize a leak detection campaign before, during and after our intervention (see diagram below). Finally, the fourth step was to celebrate our results with all the persons involved in the project. After two days on site, everyone precisely knew what was expected of him/her. 17 leaks were localized, representing potential yearly savings of 3,934 GBP (4,481 EUR or $5,111 US) and, after the quick repair of 7 leaks; actual savings of 1,648 GBP (1,877 EUR or $2,142 US) were quantified. As a result, the inspector has a better control of his/her network and of compressed air losses and actual needs; the purchasing officer can calculate the return on investment; the technician feels valued by the savings generated from his/her work; and finally, everyone is thankful to the sponsor for (re)establishing communication between the different departments.

Automatic savings sheet and automatic work order were generated by the SDT LEAKREPORTER mobile application.

Loss (£/year) = $249 US


We also share with you our LEAK MANAGEMENT: FIND-AND-FIX LEAKS PROCEDURE: An effective way to survey your systems and detect leaks.

Thank you Benoît Degraeve with SDT Ultrasound Solutions for sharing this case study with us!

by Diana Pereda

The SDT270 system was used to collect ultrasound data at a methane plant for start-up and commissioning of newly installed equipment to get a baseline condition on the motor’s and gear reducer’s bearings and gears. We were immediately able to pinpoint a defect in the drive end motor bearing using the SDT270 as well as collect and record a sound file (play below) and present it to the customer.


After removal and inspection of the motor bearing it was found that the motor had been stored in a basement and got water into it through the electrical conduit during a monsoon storm that flooded the facility in late summer, causing the bearings to rust and corrode. It was also found that the electrical disconnect box for the motor had water in it as well.

Pump: Progressive Cavity Seepex Pump

Motor: WEG 75HP 1775 RPM

Not only were we able to identify a bearing fault but also the “smoking gun” root cause, thereby thwarting further damage in the electrical system.

After troubleshooting the entire facility we were able to save several other motors stored in the basement that had also had water exposure through the electrical conduits.

Thank you Brian Franks with JetTech Mechanical LLC for sharing this success story with us!

by Ana Maria Delgado, CRL

As Published by Maintworld March 2018 issue

CRISTAL UNION (CU) is an agroprocessing cooperative company ranking among the top European sugar and alcohol producers.
Most of its facilities are established in France (18 sites). The BOURDON site in AULNAT (in the Puy-de-Dôme département) has a production capacity of 4,500 tons of beets per day.

The company contacted SDT Ultrasound Solutions regarding the implementation of a preventive maintenance program based on the collection and analysis of ultrasonic signals. This project dealt with about 400 rotating machines.

After purchasing an SDT270 ultrasonic data collector and its analysis software tool, SDT and CU have defined the outline of a training program suited to the monitoring of rotating machines. The first step consisted in creating a database containing all 300 machines and then, performing the first data collection in order to determine the initial mechanical condition of each bearing. After simple on-site analysis (ultrasonic listening) and more detailed analysis (overall or static measurements and spectral or dynamic measurements), 1 800 thresholds were defined (pre-alarm, alarm and danger).

Using these background data, technicians were then able to identify, at a glance, the machines having an alarm condition.

Click here to read the full article.

by Yolanda Lopez

While we’ve been using calendars and calculators to determine grease replenishment requirements in bearings for a long time, this science is wrong. Most bearings never reach their L10 engineered life, and poor lubrication practices are attributed as the primary failure cause.

Bearings fail when they are over-greased. We lubricate them too often, and we use too much grease.

Change Your Thinking.
We lubricate bearings to manage friction, but over time, grease gets old and needs replenishment. The first sign is when friction levels increase. Ultrasound performs well at sensing and measuring changing in friction levels. It’s the perfect technology to guide lube technicians during the lubrication-replenishment task.

Lubrication Solution
We want to grease bearings correctly. That means using the right grease, at the right location, following the right procedures and intervals, injecting the right amount, and receiving the right feedback when the task is done. New technologies from SDT are engineered to do just that.

The days of relying on calendars and calculators are over. Use our 5-Step Acoustic Lubrication Procedure  and start greasing bearings the right way!

Download our Ultrasound Lube Technician Handbook to learn more!

by Yolanda Lopez

  1. Prevent metal-to-metal contact (which creates wear particles) by using condition-based lubrication through ultrasound. Ensure the proper oil viscosity and additive package is selected and that the bearing load does not exceed its design capacity through proper installation, alignment, balancing and operation.
  2. Use desiccant breathers.
  3. Adopt an aggressive fluid management program that establishes acceptable ISO cleanliness targets for new oil by machine type. Take care to use methods of adding and sampling oil that minimize contamination ingress. These include quick connect couplers and point-of-use filtration. Install an oil recirculation system to remove particles as soon as they are created and introduced.

by Yolanda Lopez

Compressed air is the fourth most commonly used source of energy in industry. Walk through any facility and see miles of pipe transporting this house-made energy source to its point of use. On this journey its fate is undecided. Will it arrive to deliver the intended value? Or is it lost along the way?

Why Do We Tolerate Leaks?
On average, 40% of compressed air goes to satisfying the false demand of leaks. Why do we tolerate this waste in an otherwise efficient economy? Lots of reasons.

  1. Low Safety Risk?—Compressed air Leaks are rarely considered a risk. Odorless and colorless, they don’t make a mess on the floor, and we can’t hear them over plant noise.
  2. Lack of Education—Many believe compressed air is free. Yet a leak costs a thousand times more than lights that are left on.
  3. Complacency—The reliability culture does not always extend to the compressor room. Energy efficiency must be written into an organization’s aims and objectives.

Facts and Figures Don’t Lie.
Air is free. Compressed air is not. It requires another energy source to compress it. How much energy? Here’s the cost breakdown of a typical compressor system:

  • 13% CAPEX
  • 12% Maintenance
  • 75% Energy
    A small compressed air leak can cost $2,000+/year. Consider that hundreds of leaks may exist in your facility. What are you waiting for?

Leak-Management Solution
Manage your leaks with ultrasound. Their turbulent flow produces sounds that generate peaks in the 35kHz to 40kHz range—exactly where SDT’s ultrasound detectors are engineered to perform. SDT pinpoints leaks at their source, regardless of background noise.

Use our Airborne Ultrasound Leak Management: Find-and-Fix Leaks, and start reducing waste plus save money!

Download our Leak Surveyors Handbook to learn more!

by Yolanda Lopez

Are you adding grease to a bearing and not hearing any changes from your ultrasound equipment? If so, start wondering where the grease is going. It is a fact that if grease gets into a bearing the ultrasound decibel will either go down on a bearing that needs grease or go up on a bearing that is already over-lubricated.

Look for a blocked grease tube. Grease may be going into the windings on an electric motor. Do you see grease on the tube of the grease gun? Maybe a greaseable bearing was replaced with a sealed bearing at the motor shop after a repair. These are just some of the things you need to consider if you get no ultrasonic decibel change after injecting grease to a bearing.

Download 5-Step Acoustic Lubrication Procedure

by Yolanda Lopez

The diesel engine is the heart of heavy construction equipment and replacement costs are in the millions. Ingress of dust due to leaky air intake systems shreds components in short order.  The SDT TIGHTChecker quickly and easily pinpoints leaks in the air intake system.

Dust is no friend to a diesel engine. But when the integrity of the air breather and turbo charger is compromised by leaks, microscopic grains of silica and other contaminants are sucked inside. There, they wreak havoc on the engine’s internal components costing organizations millions of dollars in premature wear and downtime.

Worse yet, you may not even realize you have dust ingress unless you are conducting regular oil analysis. These leaks are nearly impossible to find using conventional methods. Visual inspection takes hours and is often unsuccessful. Production does not have the patience to wait. They need that asset back in the field, leaks or not.

But what if there was a way to identify those leaks in minutes, instead of hours? SDT Ultrasound Solutions teamed up with mining giant Rio Tinto in Labrador, Newfoundland to devise a simple procedure for identifying turbo leaks in the engines of their huge loaders.

Using SDT ultrasound technology, a transmitter is placed inside the air filter basket. The high frequency sound waves are contained inside the piping unless there is a leak. Any microscopic air gap in the pipe is instantly recognized by the handheld flex ultrasound detector.

An 8 hour inspection that often ended in frustration is now a worldwide success story that continues to save Iron Ore Company of Canada $8 million per year.

by Yolanda Lopez

Guest Tip by Bob Dunn from I&E Central, Inc.

In some environments, reflected sounds can make it difficult to locate a leak.  If you are in a confined area (a smaller room, or beneath/inside a machine), the leak can seem to be almost anywhere.  A good ultrasound leak detection solution is to adjust the sensitivity downward.  Ultrasonic sounds will reflect, but lose energy each time they reflect.  By reducing sensitivity, the reflected sounds drop into the background, allowing you to locate the actual source of the leak.

Note that SDT inspection tools have separate adjustments for sensitivity and headphone volume, so you can manage sensitivity without affecting your ability to hear!

Download our Find-and-Fix Leaks with Airborne Ultrasound Infographic!

by Ana Maria Delgado, CRL

Question: When is it OK to over-lubricate your bearing?

Answer: NEVER!!!!, (almost) the exception is when high vibration exists.

If you attended the SDT/LUDECA Acoustic Lubrication Workshops then you now understand grease as a lubricating mechanism. You understand that the Churning Phase of the lubrication task is inevitable, and long-term, detrimental to the health of the grease. Therefore, we want to move as quickly as possible from the Churning Phase to the Bleeding Phase. This is the natural progression of precision lubrication.

Grease is not a robust grease mechanism. It is actually quite fragile compared to an oil only system. But we need grease as a lubricating mechanism in bearings because the properties of grease help to keep the lubrication in and around the warzone while sealing out contaminants.

Vibration is inherent in every machine system. Excessive vibration however, negatively impacts the ability of grease to lubricate. Some machine systems are intentionally vibrated as part of their function and process. Other equipment vibrated excessively because of a defect such as imbalance, misalignment, poor installation, or poor workmanship. For these machines, it might be best practices to over-grease their bearings.

I know that sounds counter to what we teach and know, but consider this. It is better to have thickener and oil in the warzone of the bearing, than it is to set up a bleeding mechanism and have the reservoir destroyed because of high vibration. If we let this happen we may never get any oil where it’s needed.

High vibration? Slightly over grease your bearing and allow a little thickener to exist in the warzone. It is the best compromise.

Download our 5-Step Acoustic Lubrication Procedure.

by Yolanda Lopez

There are 3 techniques that can facilitate your work in the field: the shielding technique, the covering technique and reflection management.

Shielding technique protects sensor from parasite ultrasound

1. Shielding technique

This technique greatly reduces the influence of interfering leaks. It consists in using a piece of cardboard or foam(*)… to create a barrier between the “parasitic” leak noise and the location where you want to detect/locate a leak.

(*) Any material will work. It will reflect approximately 90% of the energy coming from the interfering leak.

Practical advice: the precision indicator tip placed on the internal or flexible sensor acts as a shield. This technique is very useful when leaks are very close to one another.

Covering technique blocks a known leak from disturbing detection of other leaks in proximity

2. Covering technique

This technique also greatly reduces the influence of interfering leaks. It consists in:

Either covering an interfering leak with a rag or glove while you inspect an area.

Or covering the sensor with a rag or glove in the zone you want to inspect.

A leaking valve body can be conveniently covered with a cardboard carton too.

Ultrasound signal reflecting off a wall or hard surface can be tricky

3. Reflection management

When searching for leaks, we sometimes get the impression that a leak is coming from a place where there is clearly no compressed air, such as a wall or a partition. This is due to the phenomenon of reflection. Ultrasounds from the leak are bouncing off the reflective surface. You will find the leak by following the angle of reflection. The angle of reflection is equal to the leak’s angle of origin relative to the reflection surface.

Download SDT Leak Surveyors Handbook to learn more!

by Yolanda Lopez