By Daus Studenberg – Applications Engineer

There are certain cases where it is necessary to make sure that two machines have a considerable amount of parallel radial offset. Such machines are usually coupled by a cardan shaft where more than 4-6 degrees of angle exists between the cardan coupling and the machines. Once the offset is established, it is important to ensure the machines are parallel to each other. If angular misalignment exists (i.e. the machines are not exactly parallel to each other) a rapid change in the shaft RPM will result during operation, as well as an uneven bearing loading, which could shorten the life of the machine. 

 A special cardan bracket was developed specifically for this application. Its main function is to directly translate the axis of rotation of one machine to the axis of rotation of the other machine. 
 
With the bracket installed, a simple shaft alignment occurs using an uncoupled measurement mode as laser and receiver are both turned independently  of each other to take measurements. The ROTALIGN ULTRA and the OPTALIGN SMART both feature superior single beam sensor technology that allow uncoupled measurements to be taken accurately. The ROTALIGN ULTRA takes it a step further with its useful “pass mode”. The “pass mode” automatically takes measurements each time the laser is rotated past the receiver, thus reducing the time to take measurements. 

Here’s a video of the cardan bracket and the ROTALIGN ULTRA being used for an alignment on a paper mill roll:

Is your vibration analysis program or other Condition Monitoring technology simply predicting failures or also identifying the causes of the failures?

Vibration analysis is a very useful tool for identifying failure modes in equipment. Bearing failures, unbalance, misalignment, belt issues and many other problems can be easily identified with vibration analysis. However, the value of vibration analysis goes well beyond just simply identifying what equipment is about to fail. Stopping at this level will ensure that the same failure will most likely occur again in the future and identified again in the future by your vibration analysis program or other CM technology. 

A good vibration analysis data collector and software will have tools to help you identify what is causing the bearings to fail, misalignment to occur, etc in your equipment. Use this additional functionality to identify the root causes of the equipment failures that your routine vibration analysis efforts uncover. This will allow you to eliminate the things that are causing the failures in your equipment. This means that your facility will replace less bearings, do less alignments, etc. on your equipment. This will save maintenance dollars and increase the overall reliability of your equipment.

Most facilities have multiple Condition Monitoring technologies like vibration analysis, oil analysis, thermography, etc. However, most plants do not use these CM technologies to jointly identify, confirm and report equipment issues. Do not underestimate the value of using the results generated from these technologies together.

Have you ever had a Maintenance Manager or other manager in your facility not truly understand a CM technology and discount the results?  Management may make comments like “that magical black box cannot identify this type of problem or cannot give an accurate sense of severity“.  The Analyst or Reliability Engineer knows the truth and the value of the CM technology. Consider presenting the results from multiple CM technologies together in the same report. For example, what if you went to your management with information from both oil analysis and vibration analysis? You could demonstrate that what one CM technology had identified the second technology had confirmed. This increases the credibility of the CM technologies and your reliability efforts. It becomes much more difficult for management to discount a technology when the findings have been confirmed by another CM technology.

There is more to proper shimming of a machine for alignment than meets the eye. There are several things you should keep in mind and look out for.

First and foremost, you should be using high quality precut slotted stainless steel shims, such as Lawton Precut SS-304 Shims. If you think cutting your own shims by hand out of cheaper rolls of carbon steel or brass shim stock will save you money, you are very much mistaken. For one thing, you will only be able to cut the thinner thicknesses with scissors or shears; thicker thicknesses (over 0.004″) will require the acetylene torch or sawing, which is labor intensive and presents safety concerns. After you have cut your shims by hand, you must take pains to debur them carefully with a ball peen hammer and file. All of this costs you the most valuable commodity of all: time. Moreover, the end result will be fewer available shims resulting in less precise alignments. And, if you are cutting shims by hand, don’t forget to budget the time to visit the nurse for a Band-Aid.

Download Best Practices: Machinery Alignment Shimming including:

• Advantages of Precut Stainless Steel Shims
• Number of Shims
• Shimming Technique
• Unusual Circumstances: Step-Shimming
• Chart of Horsepower Ranges and Motor Frame Numbers Associated with the Different Sizes of Shims
• and more.

Fault frequency information is very important in vibration analysis and reliability efforts.  This information allows the analyst to correlate vibration data to specific components in the equipment that may be in some stage of failure. Correctly addressing these failure conditions will increase equipment reliability resulting in greater uptime, increased capacity, improved product quality, better safety, lower costs, and reduced risks.

Bearing related failures are one of the most common faults encountered in plant equipment. Obtaining the required information to accurately determine bearing fault frequencies is a constant challenge for vibration analysts and reliability professionals.  For this reason, LUDECA has created normalized bearing information that contains approximated bearing fault frequencies without the need to know the manufacturer and other difficult to obtain bearing information. Download your copy now!

This data is also available via a file download and direct import into our OMNITREND Condition Monitoring software.

iPURCHASE, A supplement from IMPO MAGAZINE • March 2012

Companies are attempting to operate leaner and more efficiently every day, with predictive maintenance still serving as a driving force. With a variety of tools on the market, there is something for every operation, large or small.

There is so much technology available to manufacturers and distributors, it’s hard to know where to start looking, especially when it comes to industrial maintenance equipment.

Getting Started

If you’ve thought about starting up a predictive maintenance program in the past, but have shied away because of the details involved, or if you currently have a program in place and just aren’t seeing the results that you would like to see, you are not alone – this is a complex topic with constantly evolving technological solutions. And from a distributor standpoint, possessing a purchasing and sales team that truly understands the functionality and value these tools can bring to the customer is a great way to stand out from the pack. Two individuals in the predictive maintenance industry who deal specifically with vibration analysis were willing to share their scoop on the issues that they found most critical to understanding the significance of this technology.

“Predictive maintenance technologies can be applied to almost any equipment or system that has rotating, electrical or lubricated components,” notes Trent Phillips, the Condition Monitoring Manager for Florida-based LUDECA, Inc. “This includes motors, pumps, fans, gearboxes, turbines, generators, compressors, milling machines and many more. Some of the common equipment faults detected with vibration analysis are bearing defects, lubrication issues, misalignment, unbalance, gear defects, electrical problems, belt issues, resonance, looseness, foundation problems, and many more.” It looks like everybody needs predictive maintenance equipment. 

Read entire article Predictive Maintenance Technologies