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A customer with a need to monitor machinery remotely and limited to a small budget invested in the VIBCONNECT® RF system to keep their machines running. During a routine check of the data, it was noticed that a certain machine was in alarm. The OMNITREND® software easily identified the machine that was in alarm by the red indicator (see Fig. 1).

The customer contacted LUDECA to assist in analyzing the issue. The frequency did not match any of the components given for this machine. The waveform data showed extremely high levels of vibration and indicated that something was seriously wrong with this machine (see Fig. 2).

It was suggested that the machine be visually inspected for any abnormalities, including a strobe for the visual inspection. The strobe was locked into the known frequencies that were showing in alarm. The customer was able to identify that a broken belt was the cause of the high vibration levels (see Fig. 3).

New belts were installed and the pulleys were properly aligned using the DotLine Laser pulley alignment tool to prevent future belt failures due to misaligned pulleys.

Thermal growth compensation has become fairly routine among laser aligners. For machines that run at high temperatures, most manufacturers will recommend a target to align to that compensates for the thermal growth that the machine is expected to undergo. That target only tells half of the story though. In many of the situations we see, once operating, there may be more horizontal movement than vertical, and both movements are often far different from the specified amounts. These differences usually arise from sources such as pipe stress, foundation looseness, operating load variances, and other factors.

To ensure perfect alignment under operating conditions, you can monitor the positional change of machines at your plant using the ROTALIGN® ULTRA and Live Trend module. During your next shutdown, mount the lasers to the machines and monitor the cooldown. During the shutdown, align the machines using your newly discovered targets and even verify the accuracy by re-measuring the positional during start-up and run-up to final operating condition.

You’ve just completed your horizontal live move and you’ve re-measured to double-check your results. Now, it seems your coupling results are not at all what you were expecting. Does this sound familiar?

All too often when this occurs, the reasons are quite simple, such as some residual soft foot, or coupling strain that affected the accuracy of your initial readings. But if you’ve already eliminated these causes, perhaps the cause is more basic.

Double-check your dimensions screen again. It’s not that uncommon to “fat-finger” the values. Perhaps, intending to enter 2.5 inches you accidentally entered 25 inches instead! Also, make sure the units (mm or inches) are correct while you’re there.

Another often overlooked detail is the process of moving itself. Care must be taken when performing any move to prevent the laser systems heads from being bumped or jarred. Laser alignment is a very precise business and the detectors can “see” very fine movement. Unintentional movement of the laser/detector from hammer blows to the machine can cause a false reading to occur giving you an inaccurate representation of the final move result.

Always use jackscrews whenever possible!

The “Move Simulator” program is extremely useful on all types of machines but we have found it most helpful on multi-coupling train units.

We recently performed an alignment on a 350 HP turbine/gearbox/pump train in one of our cracking units. The turbine had been replaced by the area Maintenance Group and the machine was supposed to be a like-for-like drop-in exchange. This was not the case for this unit. Two problems: A bolt-bound condition and height difference on the turbine. Due to time constraints, removing the turbine and modifying support feet was not a viable option.

We used the Rotalign® ULTRA IS, took readings on both couplings and then used “Move Simulator”. We were able to adjust the gearbox height and move it horizontally to achieve acceptable alignment to the turbine. The pump side had been found almost perfect (per targets) and we ended up maintaining the offset but disturbed the angularity slightly but remained within tolerance for the coupling.

The “Move Simulator” was certainly a time and labor saving program on this occasion. —J.W., Reliability Technologist – Eastman Chemical Company

Precision alignment is an essential part of a proactive reliability program as it can eliminate many machine failures and defects. This Infographic outlines an easy and effective way to align your rotating equipment.

Download Infographic

A few weeks ago, I was at an engine manufacturing facility, training the technicians on using our ROTALIGN® ULTRA IS Laser Alignment System. They were using it to align their engines for proper testing. To begin, the technicians rough-align the engine. To test the engine, they couple it to a gearbox with a 5-foot-long spacer coupling. They set up the laser and receiver at 12 o’clock and then turn the shafts clockwise, using Continuous Sweep mode. In one instance, at about 45 degrees of rotation, they ran out of measurement range. Due to a combination of the long separation between laser and receiver, the large misalignment, and the small amount of rotation, they were not able to achieve good repeatability.

So I suggested the following solutions:

First, I recommended zeroing the laser at the 12 o’clock position but starting the measurement at around the 10 o’clock position and rotating clockwise. They were able to achieve a rotation of about 85 degrees and obtain great repeatability. The customer’s comment was “We are used to starting the measurements at the 12 o’clock position from old dial indicator practices”. It may be convenient to zero the laser in the 12 o’clock position, but you can start taking readings at any rotational position, even with the beam at the edge of the detector range. This way you can maximize the measurement range of your laser alignment system.

Secondly, I suggested that they zero the laser at 12 o’clock and start rotating the shafts while observing on the computer screen in which direction the laser beam moves on the detector. Stop the shafts and readjust the laser beam as far as possible in the opposite direction to the observed movement. Start taking readings in that position, and again this will maximize the measurement range of the detector and consequently also increase the amount of shaft rotation you can get before running out of range. If you can achieve at least 70 degrees of rotation, you will obtain accurate readings.

I also made a third suggestion: If the misalignment is so bad that you cannot obtain 70 degrees of shaft rotation before you run out of measurement range, no matter how far you initially adjust the beam in the opposite direction to its track, then use “InfiniRange”. This feature is available in the Multipoint measure mode and lets you stop to readjust the beam while taking readings, as often as necessary in order to achieve the necessary rotation to get good readings.

So, keep these ideas in mind and no amount of misalignment will ever stymie you in the field again!

Attendance at professional conferences can be expensive and remove the employee from the workforce for several days. So why allow your employees to attend a professional conference?

1. The employee is allowed to network with others performing the same job functions. This allows sharing of knowledge and experiences that can be used to make improvements in your company.
2. The employee will experience new tools,  technologies,  processes, ideas, and standards that can be used for improvements within your company.
3. The employee can demonstrate their knowledge by doing presentations, participating in subject matter forums, etc., enhancing the reputation of your company.
4. The employee can generate awareness about your company and its products.
5. The employee will return with valuable knowledge that can be shared with other employees within your company.

You are cordially invited to visit our booth at these conferences where we will be exhibiting our shaft alignment, pulley alignment, vibration analysis, and balancing products.

One of the big problems I’ve seen people run into when doing alignments is a lack of repeatability due to high vibration from nearby machinery. It’s obviously pretty difficult to align something that’s moving several thousandths. There are still ways to get accurate readings with some laser alignment tools.

Let’s say you are in the same situation but aligning with dial indicators. The indicator needle is jumping back and forth between 35 and 42. Most likely,  you will settle for the average midpoint of 38 or 39. You can do the same with lasers.

The first thing to do would be to switch over to one of the “manual” measure modes (like Multipoint mode) rather than the fully automatic measurement modes (like Continuous Sweep or Pass Mode.) In Multipoint,  you can adjust the averaging (sampling time) for each reading and spend a little more time taking each point. A longer sampling time will allow the tool to take much more data at each measurement position and average the data together very accurately, unlike guessing as with the dials. It is also a good idea to take several positions (8 or more) around 360 degrees of rotation. While the minimum required is 5 points over 70 degrees of rotation, the more points and the more rotation you have, the better your results will be. Check your repeatability. If it’s not good, look at your Standard Deviation values. These should be very low. If they’re not, then perhaps your averaging still isn’t set high enough to overcome the surrounding vibration problems. If you can’t get repeatable numbers, spend a little more time taking readings. No one likes chasing their tail making fruitless or inaccurate corrections.

Live move can also run into some problems in high vibration scenarios. Make sure you adjust the averaging value for the Move Function to the same value with which you took successful readings. It may take longer for the results screen to update but will steady the move and greatly improve its accuracy.

The thing to keep in mind is that a good laser alignment system measures down to 1/25,000 of an inch. If the laser is moving, it will affect your readings. Just know how to overcome the problems when you run into them.

We recommend that you take a look at our Alignment Matters Repeatability Video Tutorial

Putting your machines away for future use may appear a simple operation; however,  there are pitfalls that you should try to avoid. Storing machinery for certain lengths of time can bring about damage that could render that machine or some of its components inoperable to you when the time comes to use it. Here are some storage tips for success:

• First, select the driest environment available for storage. Surface corrosion is the enemy of every machine and thrives in moist air.
• Also, coat any and all exposed metal surfaces with a lubricant or oil mist to help prevent oxidation. Now that the machine and components are in storage, do not forget to maintain them. If your machine has moving parts, regular movement and rotation of its movable components will ensure that they run smoothly when brought into service.

Surprisingly, often on larger machines like gas turbines and diesel engines coupled to generators or compressors, there is less space to mount your brackets than on small machines. The large size of couplings and shafts frequently means that there is very radial clearance in the OD of the coupling hub to provide line of sight, or piping or other structures interfere with rotation, limiting your axial clearances on the shafts as well.

Also, shrouds or other obstacles limiting access to the shafts can cause difficulties in turning them. Yet, there is almost always a way to do an alignment with Pruftechnik tools. Our brackets do not need to be mounted on the shaft, provided the coupling hub is solid to the shaft (ie. rigidly mounted to the shaft.) A variety of magnetic brackets and offset adapters lets you overcome almost any obstacle to rotation or to the line of sight. In fact, anywhere that you can devise a way to mount a dial indicator, you can also mount a bracket to hold a laser component. Here are a few examples:

Here we see the ROTALIGN® SMART EX laser component and Bluetooth module mounted on a solid hub, shooting the beam through the coupling bolt hole. The laser emitter is mounted on the magnetic coupling bolt hole bracket designed for applications like this, and the Bluetooth module is mounted on a compact magnetic bracket, illustrating that the two components need not always necessarily be mounted on the same bracket. This setup allows the laser beam to be shot through an unoccupied bolt hole of the coupling without any hardware protrusion beyond the OD of the coupling.

Here we see the ROTALIGN ULTRA IS sensALIGN laser (on the right) mounted with a compact magnetic bracket to the axially protruding face of the solid hub of the double-engagement gear coupling, in a very limited axial space that would not permit a standard chain bracket to be mounted on the shaft. An offset adapter moves the laser unit forward axially, permitting the setup to overcome the axial obstruction of the machine housing at 3 o’clock.
Here we see the ROTALIGN ULTRA laser (on the right) mounted on a magnetic bolt hole bracket to the flywheel of a methane gas engine, overcoming the axial space limitations posed by the shim disk-pack type coupling.

Here we see the ROTALIGN ULTRA receiver mounted on offset support posts on a compact magnetic bracket, overcoming both an axial space limitation preventing the use of the chain brackets and a radial obstruction posed by the pipe seen in the foreground on the left.

Here we see the ROTALIGN SMART EX receiver mounted on a compact magnetic sliding bracket, overcoming both an axial space limitation and a situation in which the shaft cannot be turned by hand. Instead, the magnetic sliding bracket is slid around the solid coupling hub to each measurement position while the laser is rotated past the receiver as the other shaft is rotated using the Pass Mode measurement mode for uncoupled shafts.

Machine components are susceptible to premature wear and corrosion due in part to the harsh environments they are placed in. To combat this, here are a few suggestions to keep your machines running:

1. Proper lubrication
   Always make sure the movable components in the machine are getting the lubrication they need. Lubrication not only keeps parts cooler and moving freely but also prevents corrosion.
2. Cleanliness
   Keep the machine components as well as their environments as clean as practical. This can aid in preventing wear stemming from particle ingression and friction.
3. Keep logs
   Keep a log of all the PM (preventative maintenance) done on your machines so as to avoid duplication and prolong the life of its components.

If you follow these simple guidelines, it will help prevent breakdowns in your plant and save money.

We recently visited a water treatment plant in Boca Raton, FL, and needed to align an interesting five-machine train. The train consisted of a 1000 HP motor short-coupled  to a clutch, water pump, another clutch, and diesel engine (see Figure 1):

The main drive unit is the dark gray motor on the right, which spins clockwise and drives the blue pump in the middle through a clutch (the light gray machine.) The second clutch in the train is to the left of the pump (hidden in the picture above) and is oriented backward from the first one so as to disengage the yellow diesel engine at the far left of the train when the motor is running. When electric power fails and the motor cannot be used (such as during hurricanes or when an accident disables the electrical grid), the engine is automatically started and spins counterclockwise, driving the pump in the same direction as before through the left-hand clutch, whereas the right-hand clutch now disengages the motor from the train. It is an ingenious arrangement, designed to keep this critical machine train operational even if one of the drivers were to fail. Some vibration trouble was being experienced and misalignment was suspected.

We brought a ROTALIGN ULTRA IS to the site with four sets of sensALIGN heads. Using the multi-coupling measurement feature in the ROTALIGN (available with the Expert level of the firmware), we were able to take a set of readings across three of the four couplings simultaneously using the Continuous Sweep mode in just minutes. However, since the diesel engine is disengaged from the rest of the train while rotating clockwise from the motor, its shaft does not turn with the rest of the train. This problem was overcome by uncoupling it from its clutch and using a turning gear to rotate the engine shaft separately while utilizing the Pass Mode measurement mode for uncoupled shafts across this coupling.

Although short-coupled with double engagement gear couplings, the fairly large size of each of these couplings meant we could treat them as spacer couplings since the 8-inch span between the ring gears is greater than the minimum 4″ distance between flex planes recommended to consider the coupling as a short coupling.

As the diesel engine was manually turned with a turning gear to various positions, the sensALIGN laser on the clutch shaft passed the sensALIGN receiver on the engine shaft several times during the rotation of the train. This way, the entire train alignment could be captured with just one rotation of the shafts:

After the readings were completed, it was time to look at the results. We zoomed the view out to look at the overall alignment of the entire machine train and found this situation in the vertical plane, with the diesel engine on the left set as the reference machine:

The results showed that the pump would have been dropped by nearly 20 thousandths at the left pair of feet and nearly 30 thousandths at the right pair of feet. Since it would be very difficult and inconvenient to move this heavily piped pump, we decided to explore alternatives by using the Static Foot function to set the Pump stationary as well. This meant that ROTALIGN would now draw a new optimized centerline through the two stationary machines (the engine and pump) and show us the relative positions of the remaining three machines with respect to this optimized centerline, as shown below:

Since the motor too was large and inconvenient to move, with heavy, inflexible conduit connections, we decided to explore whether alternative shimming solutions existed to achieve a satisfactory alignment by moving only the two clutches in the train. To this end, we now opened the shimming and move simulator in the Rotalign Ultra and discovered that we could in fact achieve an excellent alignment throughout the entire train by moving just the two clutches to get into spec. The left-hand clutch (coupled to the engine) could be shimmed up by 10 thousandths at the left pair of feet (closest to the engine) and shimmed up 13 thousandths at the right pair of feet (nearest the pump.) This would achieve an excellent alignment between the clutch and the pump on the right side without compromising the already good alignment between the clutch and the engine on the left side, as illustrated below.

Next, we would pivot the right-hand clutch (nearest the motor) by raising its left pair of feet (nearest the pump) by 9 thousandths while at the same time lowering its right pair of feet (nearest the motor) by 9 thousandths as well. This would simultaneously achieve an excellent alignment of this clutch to both motor and pump. See below:

Leaving the sensALIGN components installed, we were able to monitor the alignment throughout the entire train live as the corrections were made at the two clutches. After the shimming corrections were completed the entire train was remeasured and was found to be within tolerance, with no further shim changes or horizontal moves required.

The entire alignment of this five-machine train was accomplished in just 4 hours and 37 minutes using the Multicoupling feature for simultaneous measurement across all four couplings, the Continuous Sweep and Pass Measure Modes, the Shimming Simulator, and Live Move feature of the ROTALIGN ULTRA IS. Only a tool like the ROTALIGN ULTRA IS could have allowed us to accomplish this complex task with such speed and ease.

The machine owner informed us afterward that this alignment typically scheduled at least two man-days with traditional methods and was very pleased to get his critical machine train back online so quickly, saving lots of money in the process.

Purchasing a condition monitoring tool is one step in your journey to implementing a reliability program. Proper training on how to use the new technology,  planning the work correctly,  ensuring the work is completed on schedule and done so correctly is critical to success. Just as important is understanding the risks associated with your equipment, especially when it fails. A criticality assessment along with failure modes and effects analysis will help you understand those risks and determine where to focus your maintenance activities.

I recently spoke to a plant engineer that had purchased alignment equipment and vibration equipment from LUDECA. He had performed several alignments and collected baseline vibration data. The decision was made to start aligning machines that required maintenance and this was a wise choice to ensure failure modes were not inserted into equipment during routine maintenance activities. Unfortunately, this facility had not performed a criticality assessment on their machinery! It turns out that the plant had a catastrophic failure on a piece of equipment that was vital to the overall production processes of the plant. The first comment made was “why did we have this failure when we recently invested in alignment and vibration equipment?”

You must fully understand the risks to safety, production, environment, and profits that your equipment imposes on your facility. As you can see from the example above, not understanding these factors may lead to continued equipment failures and their undesired consequences. To ensure that you do not continue to experience maintenance failures requires that you fully comprehend the risks that each piece of equipment entails. Had this facility understood the failure modes and the (criticality/risk) impact each machine posed, they would have been able to focus their maintenance efforts where they were most needed to keep the plant efficiently operational.

As part of this endeavor, it is important to apply condition monitoring (vibration analysis and properly targeted alignment, among other things) on the equipment within your plant, because it is extremely difficult to be reliable without doing so. However, you must understand how and where to direct those efforts to ensure that unwanted risks are reduced. Understanding how your equipment can fail (FMEA), the consequences of those failures (RCM or risk assessment), and what equipment is most important to keep your plant operational (criticality assessment) are all important to ensure that your maintenance efforts are properly focused. These efforts may avoid the experience this facility had and prevent your plant from experiencing the same unwanted effects.

SOLAR gas turbine centering tool with X-Y tracking

The centering tool for SOLAR TURBINES is based upon shaft travel in the vertical plane. As the top knob is turned,  a plunger pushes the shaft from the top position all the way down to the bottom position. The tool allows the technician to count the number of turns of the top knob to determine the amount of travel of the shaft. Upon traversing the full extent of the travel range from top to bottom,  the technician then applies only half the number of turns in the opposite direction to return the shaft to the center of its vertical travel range. Performing this task with the ROTALIGN® ULTRA laser shaft alignment system allowed this job to be performed much more accurately. The laser/sensor combination takes the centering of the shaft to a new dimension by tracking not only the shaft’s vertical position but its horizontal position as well.

LUDECA’s donation of its laser alignment system to Midlands Technical College prepares students for the real world.

  
Matthew Lester,  an industrial training instructor for Midlands Technical College,  was mindful of the good that would come from the donation of equipment from LUDECA. When Midlands Tech finally received the laser alignment systems and equipment, his dream of helping students prepare for their future jobs came true. Read the rest of the blog by Plant Services Magazine.

You’ve always heard the adage,  “Laser on the Stationary and Receiver (or Prism) on the Movable.”  In this day and age, however, this “truism” has become obsolete. You see, the concept of the “stationary” machine, per se, is obsolete. ALL machines CAN be moved if they really need to be (no machine grew out of the ground, like a tree!), so instead, we emphasize that the laser should be mounted on the machine that is “more difficult” to move (usually the pump because of the connected piping.)

The flexibility that all ROTALIGN® (and OPTALIGN SMART® products) offer through their static feet function, as well as the ability to freely flip or rotate the view of the machines to suit your needs, means that you no longer need to concern yourself with “stationary” machines. Your real goal is to find the easiest and most expedient way of aligning your machines. In some cases, this may mean moving one pair of feet on the pump just a little to keep from having to move the motor feet a lot.

So, let’s just amend our setup statement a bit: I always say “LLLaser on the LLLeft and RRReceiver on the RRRight!” (or RRReflector, as the case may be.) This will help you to remember and keep your setups consistent. But what if your pump and motor are mounted close beside a wall, and you can only access the machines from one side? As luck would have it, that side is always “the wrong side” as dictated by Murphy’s law, with your pump on the right and the motor on the left, instead of the way you are used to seeing them. No matter! Still, mount your laser on the left machine. Now, since the Rotalign and Optalign want to move the right machine by default, you can now employ the “Flip Machines” feature, which will automatically swap the view of your machines left and right, so you can see them the way they really are in the field, and easily move the left machine now, even if you have mounted your laser on it.

If you have two equally hard-to-move machines, each of which you would ordinarily like to consider stationary (such as a heavily piped little steam turbine driving a heavily piped compressor), then it really just boils down to which machine (or combination of feet on both machines) is the most expedient to move. Again, mount the laser on the left. You can always use the static feet function to declare the machine on the right stationary and make the machine on the left movable or ask the tool to make any combination of feet movable so as to find your smallest possible moves or optimal combination of moves to solve bolt-bound or base-bound situations in the field. The ROTALIGN ULTRA products are especially versatile for this, since they let you explore fully optimized centerlines (move ALL the feet in the train), as well as under-constrained and over-constrained centerlines, to cope with the exigencies of the situations you encounter in the field.

Lastly, if you ever need to compare your alignment or your target specs to a drawing or to someone else’s report that shows the machines the other way around from the way you set up, you can always use the Rotate View functionality to look at your results from the other side. You use this feature “after the fact”—in other words, after your setup is already complete, with readings taken and results obtained, you can always rotate the view and see your results as if you had walked around to the other side of the machines.

To summarize, the concept of “stationary” and “movable” is history. Use the Flip View feature right at the beginning, when you set up, to make your setup conform to the actual situation in the field. Use the Static Feet Function to make any machine movable or stationary, and to explore “best possible” correction alternatives.

Lastly, use the Rotate View feature to look at your alignment differently, after it’s already done.

Learn how these features work in the ROTALIGN ULTRA, OPTALIGN SMART, and SHAFTALIGN® laser shaft alignment systems.

At Enterprise Products an 8000 HP Siemens Electric Motor is short-coupled to an Ariel KBV six throw compressor. Unit was suffering from very large amounts of vibration causing excessive wear and tear on various components of the machine.

This alignment is performed using the compact magnetic brackets attached to a huge Thomas shim disk-type coupling. The shafts are turned using their 15-ton overhead bridge crane with a suitable nylon strap. The alignment was performed using the OPTALIGN® SMART alignment system and the Multi-point Measure Mode. To take readings,  the unit must be turned with a 15-ton overhead crane. Since the rotation is not even and start-stop positions cannot be exactly controlled, measurements are taken at various locations along the rotation. The Multi-point Mode is ideal for this situation.

I have been using OPTALIGN SMART Laser Equipment for years. The OPTALIGN SMART makes it simple and easy to align very small equipment as well as very large equipment. We use the OPTALIGN SMART to align all rotating equipment in our facilities. The two pieces of equipment grow together within .001” to .002”. This was confirmed when a hot alignment was performed. We check alignment both hot and cold every 4000 hours of run time. The OPTALIGN SMART takes the guess work out and definitely saves valuable time.” —D. Thomas, Enterprise Products

When performing shaft alignment,  the most important goal is to align the machine to within proper tolerances.

One criterion that has an impact on the tolerances that should be used is identifying and selecting the correct coupling type. In the setup shown below in Figure 1, spacer coupling tolerances were being used. However, in order to achieve a proper alignment, the alignment should have been performed using short flex tolerances.

Between the two shafts, a long coupling is used to connect them, however, the connection between the motor shaft and the spacer (left side in the picture) is rigidly coupled and has no flexible element. Thus this setup should be treated as a continuous extension of the motor shaft. Therefore, the alignment should be performed using the short flex tolerances at the flexible coupling on the right side. Spacer tolerances should only be used when the distance between the two flex planes of coupling is four inches or greater.

Happy to share two great articles by MAINTENANCE TECHNOLOGY Magazine about The Importance of Shaft Alignment and Precision Shaft Alignment For Improved Uptime:

1. The Importance of Motor Shaft Alignment
2. Motor Shaft Alignment For Improved Uptime

Maritime Reporter & Engineering News • AUGUST 2014

If you operate a vessel,  its machinery, without a doubt, will require alignment many times during the course of its life. When misalignment is present components will be worn, efficiency will be lost, and, if left uncorrected, mechanical failures are imminent. This translates into a strain on mechanical systems, your budget, and your peace of mind.

When speaking of alignment in marine applications, it is usually shaft alignment that is being referenced…

Read the entire article Laser Alignment – Keeping Your Machinery in Line to Maximize your Bottom Line by our client AME Solutions featuring our ROTALIGN® ULTRA laser alignment system