vibelube

Condition Monitoring Blog
Vibration Analysis, Thermography Inspection, Oil Analysis, Motor Current Signature Analysis, Ultrasonic Evaluation
Update Your Knowledge
Predictive Maintenance, Reliability Programs, Condition Based Maintenance, Precision Maintenance, Dynamic Balancing, Machinery Alignment
Previous
Next

The Importance of Correct Oil Sampling for Machinery Oil Analysis

Oil sampling is one of the most important parts of any oil analysis program. In fact, the effectiveness of the whole program depends on the suitability of the sampling practices.

Any good sampling practice should address below items:

    • When?
    • Which tools?
    • Which method?
    • How much?

The oil analysis will fail to reach to its goals if it is not accompanied with correct sampling practices. This post is a quick review on the most important aspects of a good sampling practice (coming soon).

 

 

Resonance Correction

Resonance occurs when a machine generates vibration at a frequency close to a natural frequency of
the rotor or structure. Resonance greatly amplifies the vibration amplitude; the high vibration
amplitude reduces the life of the bearings and the machine structure. The vibration analyst can get
involved in two ways:

  1. First the vibration analyst can identify the source of vibration that is exciting the natural frequency and seek to reduce that vibration amplitude. For example, if there is unbalance which is exciting the natural frequency then one solution is to simply balance the machine.
  2. The second way that the vibration analyst can help is to perform tests that identify the natural frequencies and then propose modifications to the structure so that the natural frequencies no longer correspond to the frequencies being generated by the machine. The most common situation is where the running speed of the machine corresponds with the natural frequency, however other sources of vibration such as the pump vane rate, blade passing frequencies and other can also excite natural frequencies. It may be necessary to increase the stiffness of the structure to increase the natural frequency so that it is no longer excited by the vibration generated by the machine.

Commissioning

There is often an assumption that components, lubricants and the machines themselves are in perfect condition when they are purchased. Sadly, this is not always the case. Bearings may not be transported or stored correctly and may suffer from false-brinelling. Lubricants may not meet cleanliness standards.Rotating machinery may suffer from resonance and other conditions when operated under normal conditions. Too often rotating machinery are not designed with energy efficiency and reliability in mind; instead they are designed with purchase cost in mind.

Acceptance testing provides a way to test that machines and components are in good condition before they are installed in the plant. Acceptance testing puts pressure on the supplier to make sure they are delivering the highest quality products. Acceptance testing guidelines can include specifications on several parameters, but from the vibration analyst’s perspective the key standard is to set vibration limits that may not be exceeded. Tests may be performed at the OEMs workshop or after being installed on-site. It is important the conditions for the test are clearly specified, including RPM, load, and mounting. Acceptance testing should not only be performed on new equipment, it should be performed when repair and overhaul work is performed. This can include motor rewinds, rotor balancing, and pump or compressor rebuilds.

Vibration Analysis

Any abnormal noise, vibration, temperature, pressure and current draw are indication of a problem or defect in machine components. If left unattended, the defect can progress to a failure and costly repairs. On-site mechanical inspection and hands on examination is a significant part of any machinery diagnosis. Vibration analyst collects vibration data as well as other parameters and performs analysis for detecting defect(s) followed by corrective actions.

Unbalance, misalignment, incorrect belt tension, poor lubrication practices, incorrect machine operation, and resonance are common root causes of failures in rotating machinery, however many others exist. Whenever the vibration analyst detects a fault in the machine, he or she should always attempt to determine the root cause. Once the root cause is identified measures should be taken so that root cause is eliminated. It is clever to be able to detect a bearingdefect, but it is not very clever if the same bearing exhibits the same fault condition just months later. The vibration analyst will need to determine the most appropriate action that he or she can take at their place of work to avoid a repeat of the fault.

mechanical vibration control

Condition Monitoring

Condition Monitoring (CM) which is often referred to as Predictive Maintenance (PdM) is monitoring of
parameters such as vibration, noise, temperature, pressure and current on machine components for
tracking changes and verifying its condition. Monitoring can be done periodically or continuously.
Vibration Analysis as a key component of a CM/PdM program will always be required, even when the
best reliability improvement programs are well-established.

VibeLube is a premier provider of predictive machine condition monitoring and analysis services that
align with customers’ high standards for reliability, availability and uptime. VibeLub’s Reliability Services
utilize flexible deployment models, proven diagnostic software and unmatched analytical expertise to
deliver sustainable, scalable and cost-effective condition-based maintenance programs. The company’s
bundled solutions enable customers to choose comprehensive, proven programs that ensure asset
availability and maximize productivity.

Predictive Maintenance

Condition Monitoring (CM) which is often referred to as Predictive Maintenance (PdM) is monitoring of parameters such as vibration, noise, temperature, pressure and current on machine components for tracking changes and verifying its condition. Monitoring can be done periodically or continuously. Vibration Analysis as a key component of a CM/PdM program will always be required, even when the best reliability improvement programs are well-established.

VibeLube is a premier provider of predictive machine condition monitoring and analysis services that align with customers’ high standards for reliability, availability and uptime. VibeLub’s Reliability Services utilize flexible deployment models, proven diagnostic software and unmatched analytical expertise to deliver sustainable, scalable and cost-effective condition-based maintenance programs. The company’s bundled solutions enable customers to choose comprehensive, proven programs that ensure asset availability and maximize productivity.

Troubleshooting

Any abnormal noise, vibration, temperature, pressure and current draw are indication of a problem or defect in machine components. If left unattended, the defect can progress to a failure and costly repairs. On-site mechanical inspection and hands on examination is a significant part of any machinery diagnosis. Vibration analyst collects vibration data as well as other parameters and performs analysis for detecting defect(s) followed by corrective actions.

Unbalance, misalignment, incorrect belt tension, poor lubrication practices, incorrect machine operation, and resonance are common root causes of failures in rotating machinery, however many others exist. Whenever the vibration analyst detects a fault in the machine, he or she should always attempt to determine the root cause. Once the root cause is identified measures should be taken so that root cause is eliminated. It is clever to be able to detect a bearingdefect, but it is not very clever if the same bearing exhibits the same fault condition just months later. The vibration analyst will need to determine the most appropriate action that he or she can take at their place of work to avoid a repeat of the fault.

mechanical vibration control

Precision Alignment

Mass Imbalance, as well as Shafts Miss-Alignment are the most common causes of high vibrations in rotating equipment. Balancing reduces rotating forces which can damage bearings and the machine structure. Likewise shaft alignment reduces the stress on bearings, couplings, and the shaft itself. For smooth & safe operation of any rotating equipment, it is recommended to check vibrations and perform balancing & alignment, particularly when they are new installed machines or newly repaired or
overhauled.

VibeLube offers expert field balancing, alignment and vibration analysis services. We bring extensive experience along with the most advanced portable instrument and software to your plant to perform an excellent job.

Dynamic Balancing

Mass Imbalance, as well as Shafts Miss-Alignment are the most common causes of high vibrations in rotating equipment. Balancing reduces rotating forces which can damage bearings and the machine
structure. Likewise shaft alignment reduces the stress on bearings, couplings, and the shaft itself. For smooth & safe operation of any rotating equipment, it is recommended to check vibrations and perform balancing & alignment, particularly when they are new installed machines or newly repaired or overhauled.

VibeLube offers expert field balancing, alignment and vibration analysis services. We bring extensive experience along with the most advanced portable instrument and software to your plant to perform an excellent job.

Acceptance Testing

There is often an assumption that components, lubricants and the machines themselves are in perfect condition when they are purchased. Sadly, this is not always the case. Bearings may not be transported or stored correctly and may suffer from false-brinelling. Lubricants may not meet cleanliness standards.Rotating machinery may suffer from resonance and other conditions when operated under normal conditions. Too often rotating machinery are not designed with energy efficiency and reliability in mind; instead they are designed with purchase cost in mind.

Acceptance testing provides a way to test that machines and components are in good condition before they are installed in the plant. Acceptance testing puts pressure on the supplier to make sure they are delivering the highest quality products. Acceptance testing guidelines can include specifications on several parameters, but from the vibration analyst’s perspective the key standard is to set vibration limits that may not be exceeded. Tests may be performed at the OEMs workshop or after being installed on-site. It is important the conditions for the test are clearly specified, including RPM, load, and mounting. Acceptance testing should not only be performed on new equipment, it should be performed when repair and overhaul work is performed. This can include motor rewinds, rotor balancing, and pump or compressor rebuilds.