Tagged: lubrication

Lubrication Explained

What is Lubrication?

Lubrication is the process of reducing friction, wear, and heat between moving surfaces by introducing a lubricating substance, such as oil or grease.

The Purpose of Lubrication

If you walk into any industrial facility, you will find lubricants. While they come in all types of textures (greases or oils), viscosities, and packaging, one thing remains true: We need them. Lubricants were designed to reduce friction as their main function. However, that’s not their only use.

Although lubricants can effectively reduce friction, they can also reduce or transfer the heat built up in machines. This only applies to oils circulated through the systems and not grease that remains in place.

Additionally, lubricants can minimize wear by providing an adequate film to separate surfaces from rubbing on each other.

The 6 Functions of a Lubricant

Lubricants also help improve the efficiency of the machine by removing heat and reducing friction. They can also remove contaminants (for oils that are circulating, not grease) and transport them away from the machine’s internals. This is due to some additive technologies (such as dispersants or detergents).

Depending on the type of lubricant or its application, its function can also change. For instance, hydraulic oils are specifically used to transmit power, something that gear oils or motor oils cannot do. On the other hand, the lubricant can be considered a conduit of information if condition monitoring is considered.

Lubricants provide several functions depending on their application and environment. However, the main functions of a lubricant include reducing friction and wear, distributing heat, removing contaminants, and improving efficiency.

How Lubrication Reduces Friction and Wear

At the heart of lubrication is the main function of overcoming friction. When two parts move or two surfaces rub against each other, microscopic projections called asperities exist. Even on what appears to be smooth surfaces, asperities exist, and when these move over each other, friction is produced, which in turn can generate heat and cause wear.

Wear can typically occur in various forms, but in many of these, the touching of the asperities serves as the trigger point for wear to occur.

This is where lubricants really make a statement. They serve to provide a barrier between the two surfaces, almost allowing them to float over each other seamlessly. As such, friction is reduced once the asperities are kept apart, and this even influences a reduction in the occurrence of wear.

Wear can typically occur in various forms, but in many of these, the touching of the asperities serves as the trigger point for wear to occur. With the presence of the appropriate viscosity of lubricants, these asperities can be kept apart, and the occurrence of wear can be diminished significantly.

The Role of Lubrication in Preventive Maintenance

As we have noted above, proper lubrication can help to prevent wear. This is one of the many characteristics which make it ideally suited as a tool for preventive maintenance.

As defined, preventive maintenance can help maintenance professionals schedule time-based tasks / prescribed intervals¹. Any maintenance manual will include prescribed intervals at which lubricants should be changed (typically after 500 hours or 5000km).

OEMs (Original Equipment Manufacturers) defined these intervals as general guidelines for machine operators. This gives operators an idea of the lubricant’s expected life or the duration after which it would no longer be able to perform its functions adequately. By changing the lubricants at these intervals, one could avoid unplanned downtime.

Another aspect of lubrication associated with preventive maintenance is relubrication intervals. In some machines, there are minimum required reservoir levels that need to be maintained.

However, depending on the system, there may be some expected loss of lubricants during its lifetime. As such, relubrication intervals can help prevent unwanted downtime by injecting new oil or grease (with fresh additives) and maintaining the required reservoir levels.

Find out more in the full article featured in Precision Lubrication Magazine.

Oil Properties / Storage & Handling of Lubricants

Storage and Handling & Advancements in Hydraulic oils

Hydraulic systems have smaller clearances than many. As such, it is imperative that these oils be kept clean and free from any debris. Most hydraulic components have a required ISO 4406 rating that should be met to ensure that the oils do not allow foreign particles to enter as these can easily clog the clearances and cause the system to stop working.

Chevron Lubricants produced a document that compiles some ISO 4406 codes for various types of industrial off highway equipment, which also includes the hydraulic standards. It noted the recommended ISO Cleanliness for John Deere hydraulic Excavators can be ≤23/21/16, this can be found here (Chevron Lubricants, 2015).

Hydraulic oils should be pre-filtered before being placed in your equipment even though there are filters on the inside of the equipment by reducing the amount of contamination entering the system from the onset, you can ensure a longer life for your hydraulic oil. Hydraulic oils should also be stored in closed containers not those that are left open to the atmosphere!

Advancements in Hydraulic Oils

According to (Fitzpatrick & Thom, 2021), the hydraulic oil market was approximately worth USD 77.5 billion by the end of 2021. Mobile hydraulics account for 65% of the market while industrial equipment represents 35% of the market. Clearly, the larger market share exists for mobile hydraulics. However, OEMs are also moving towards smaller oil sumps with longer oil drain intervals that can impact on the volume of hydraulics needed periodically.

Changes by OEMs also impact the formulation of hydraulic oils. For instance, if a smaller sump is used then, the hydraulic oil must now be able to cool faster, transport the same (or larger) force and maintain the intended viscosity of operation while being under greater stress. In these cases, the additive packages involving the antiwear, thermal stability, viscosity index improvers, defoamants and dispersants must be formulated to work in unison without compromising the other.

There have been changes in additive technology that allow for larger tolerances for various characteristics but while additives are evolving, the refining of base oils is also trying to keep up. With all of these evolutions, the chemical composition of hydraulic oil today vastly differs from one created in the 1950s. The requirements of hydraulic oil have also greatly evolved, forcing these changes in formulation.

Hydraulic oils today need to provide longer oil drain intervals, better stick/slip characteristics, increased efficiency, improved conductivity and wear performance and an added level of sustainability. Formulators need to create hydraulic oils that can adhere to these characteristics while also not infringing on regulatory requirements. This makes hydraulic oils one of the most powerful types of oils because they must conform to these requirements while also transferring force from one place to another.

References

Chevron Lubricants. (2015, January 24). Chevron Lubricants Latin America. Retrieved from Chevron Lubricants: https://latinamerica.chevronlubricants.com

Fitzpatrick, A., & Thom, M. (2021, November 08). How the Global Hydraulic Fluid Market Is Changing—And What It Means for the Future. Retrieved from Power Transmission Engineering: https://www.powertransmission.com/blogs/1-revolutions/post/189

Mang, T., & Dresel, W. (2007). Lubricants and Lubrication Second Edition. Weinheim: WILEY-VCH.

Pirro, D. M., Webster, M., & Daschner, E. (2016). Lubrication Fundamentals, Third Edition Revised and Expanded, ExxonMobil. Boca Raton: CRC Press, Taylor & Francis Group.

Find out more about the article featured in Equipment Today Magazine.

Oil Properties

Are Consolidation and Cheaper Hydraulic Oils Worthwhile Considerations?

Given the various types of hydraulic oils that exist, can they all be consolidated into one hydraulic oil that can serve the purpose for all the applications? The short answer is no, the longer answer is that if there is overlap among OEM recommendations within the same viscosity, then there is a possibility of consolidation. Typically, OEMs will provide guidelines on the oils recommended for use and they should be sought out for these consolidations as they will be more familiar with compatibility issues, as well.

On the other hand, it may mean that the hydraulic storage area of the warehouse has numerous hydraulic oils. In this case, a proper labelling system should be in place to ensure that the correct oil gets to the right location. Since these are specialized, using an incorrect oil (or an oil that does not meet the right specification) can result in disastrous outcomes for the equipment especially for compatibility challenges.

Are Consolidation and Cheaper Hydraulic Oils Worthwhile Considerations

One of the most common issues with hydraulic equipment is the existence of leaks. Depending on the application, some owners prefer not to fix the leaks and use cheap hydraulic oil to keep the equipment working. However, this is not the best practice.

When hydraulic oil leaks out into the environment, this can be hazardous to the people on the site (spills or trips), equipment (skids or contamination) and the environment since it was not disposed of properly. By using cheap oil, this can also damage the equipment even more as that oil may not meet the OEM requirements. In these cases, more harm is being done to the environment and the equipment and there can be significant losses financially and operationally.

This is where the quality of the oil and operations (no leaks) can trump quantity (excess volumes of cheaper oil). Unless the leaks are fixed, then the volume of cheaper oil will continue to increase and there will be additional labour costs to constantly maintain the sump levels as well as delays to the project.

Therefore, the overall impact on the efficiency of the hydraulic equipment will be reduced. However, if the leaks are fixed and a quality hydraulic oil is used, then the machine can operate more efficiently, complete the assigned projects and possibly even reduce extra labour costs related to maintenance.

Ideally, consolidation can be achieved as long as the OEM requirements are being fulfilled. However, cheaper oil that does not meet the required OEM standard for a particular piece of equipment is not an ideal option as it can cause more harm than good in the long run.

Find out more about the article featured in Equipment Today Magazine.

Oil Properties

Are There Different Types of Hydraulic Oils?

Similar to there being endless types of greases, there are also many types of hydraulic oils specifically designed for certain systems. Hydraulics comprise of lots of different operations as such, they will be called upon to perform in various applications. Some of these can include being fire resistant, biodegradable or even being able to also act as an engine oil. These properties can be influenced by the type of base oil used to produce these oils. For example, fire resistant or rapidly biodegradable fluids or even specialty hydraulic fluids can use PAOs (Polyalphaolefins), PAGs (Polyalkylglycols), POE (ester oils) or other synthetic oils as their base oil.

As per (Mang & Dresel, 2007), hydraulics require special types of additives for their applications. The most important additives for hydraulic oils are:

“Surface active additives” – For hydraulic oils these can be rust inhibitors, metal deactivators, wear inhibitors, friction modifiers, detergents / dispersants, etc.

“Base Oil active additives” – For hydraulic oils, these can be antioxidants, defoamers, VI Improvers, Pourpoint improvers, etc.

Typically, the additives for hydraulic oils can be broadly classed into those which contain zinc and ash and those which do not. Zinc and Ash free oils can represent 20-30% of hydraulic oils on the market and are used for specialty applications where the presence of zinc or ash can hamper the functionality of the equipment.

One such example is the use of these oils in the JCB Fastrac 3000 series for the hydraulic oils. These systems contain yellow metals which can be easily degraded with the presence of zinc or the filterability of the oil can be impacted due to the presence of water. Hence, zinc and ash free oils must be used in these instances.

The following shows a chart of the types of hydraulic fluids as per (Mang & Dresel, 2007) broken down by hydrokinetic applications, hydrostatic applications and mobile systems.

Figure 1: Classifications of hydraulic fluids as per (Mang & Dresel, 2007) Chapter 11, figure 11.9.

As seen above, there are many different classifications of hydraulic oils. To provide some clarification on the symbols used in DIN 51 502 and ISO 6743/4, (Mang & Dresel, 2007) produced this table.

Figure 2: Classification of mineral oil-based hydraulic fluids as per (Mang & Dresel, 2007), Chapter 11, Table 11.3.

When looking at hydraulic oil classifications, these categories will come up and it is important to be able to understand what each of these mean as well as how it translates to your system. Typically, the most common are the ISO HM and ISO HV.

The ISO HM refers to oils with improved anti-wear properties used in general hydraulic systems with highly loaded components and where there is a need for good water separation operating in the range of -20 to 90°C.

The ISO HV oils are HM oils with additives that improve viscosity-temperature behavior. Ideally, these are used in environments that experience significant changes in temperatures, such as construction or marine, between the ranges of -35 to 120°C.

Find out more about the article featured in Equipment Today Magazine.

Oil Properties

What Are The Functions of Hydraulic Oils?

Hydraulic oils are used in many areas of our life, from the telescopic booms of cranes to the control valves in a tractor. These oils are special as they perform a particular function which is unique to them. In addition to the regular functions of an oil, hydraulic oils can transmit power which truly sets them apart. In this article, we will take a deeper dive into the world of hydraulic oils, how they can be used, ways that they should be stored and handled and of course some advancements that we’ve seen over the years.

What Are The Functions of Hydraulic Oils?

Before going any further, we must understand how hydraulic oils function and the impact that they create for our equipment. As per (Pirro, Webster, & Daschner, 2016), the concept of hydraulics revolves around the transmission of force from one point to another where the fluid is the transmitter of this force. Ideally, this is based off Pascal’s Law where, “The pressure applied to a confined fluid is transmitted undiminished in all directions and acts with equal force and at right angles to them.”

As applied to hydraulic oils, once a force is exerted on an oil, the oil can transmit this force to either help an actuator turn or stop an excavator from moving (through braking). This is the transmission of pressure, but hydraulic oils can also provide the functions of reduced wear, prevention of rust and corrosion, reduction in wear and friction and an overall improvement in system efficiency.

For anyone who has worked with hydraulic oils, they will be familiar with the fact that these oils have very tight clearances which requires them to be clean. As they are transmitting power through the fluid, having clean hydraulic oil is essential, so this flow is not disrupted. Since the force will be the same throughout the lubricant, having these tighter clearances allows for more force to be output per square area at the intended target without the contaminants.

Overall, hydraulics will perform the regular functions of an oil but with the added benefit of the transmission of force for these applications. But not all hydraulic oils are created equally and some need to be specifically designed for particular applications within our industry.

Find out more about the article featured in Equipment Today Magazine.

Used Oil Analysis

The Hybrid approach – Sensors & Labs

By Sanya Mathura (Strategic Reliability Solutions Ltd) & Neil Conway (Spectrolytic)

The above offers some advantages of using these inline sensors but what really sets the FluidInspectIR apart?

Historical inline sensors have employed dielectric or impedance-based sensing. Impedance based sensing is slightly more advanced than dielectric sensing but still only measures a few electrical parameters such as oil resistance, capacitance and inductance which assist in detecting the polar molecules in the oil.

However, complex algorithms are usually used to convert the electrical data into a meaningful value such as TBN or develop a trend based on a dimensionless value. Laboratories use MIR Spectroscopy which is the same technology utilized by FluidInspectIR. As such, the data / results are given in the same units and accuracy as labs.

The FluidInspectIR technology analyses the spectra in the wavelength ranges which have a chemical meaning for the application in which the sensor is being used, such as turbine oils, EALs, gear oils, engine oils etc. This specificity in the MIR spectrum, coupled with several mechanical and electrical design features allow lab accuracy in the field.

Figure 4: Market validation and asset examples

The Hybrid approach

While the FluidInspectIR Inline sensors can provide actionable data required for preventive maintenance strategies, there are some parameters where a lab analysis would certainly be advisable. These are more specialized tests such as Air separation / Demulsibility or FZG loading tests which require some fairly complexed processes in which the oil has to stand for some time during the procedure or different loads have to be added until a particular characteristic is met.

With that being said, inline OCM technology has made significant advancements and the FluidInspectIR is currently considered state of the art providing lab equivalent data in real time. In addition, it is also capable of measuring nonstandard properties, such as oxidation by-products which can relate to varnish by-products or the potential to form varnish as well as monitor the quantity of antioxidants. The monitoring of these parameters could not have been done a decade ago as the technology simply wasn’t available.

The future of oil analysis will certainly be a hybrid approach where inline sensors continuously monitor the fundamental parameters and when limits are reached (either below or above), or the trending analysis shows a peculiar behavior, then specialized additional testing can be pursued using the lab infrastructure and expertise.

In this way, resources are conserved when the oil appears to be within its limits and functioning as it should. However, when these limits are reached and the component could be in danger, specialized resources will be deployed to ensure that the component does not suffer a fatality. The way forward for oil analysis is definitely a hybrid approach mixing the traditional with some of the cutting-edge technologies.

Bio:

Neil Conway – Applications Manager, Spectrolytic

Neil is the Applications manager for Spectrolytic where he develops and manages new and current measurement applications for all the product lines. Neil is also extensively involved in sensor characterisation, product development, customer training, and technical marketing.

Previously Neil has held Process Engineering positions in semiconductors with Motorola and Atmel and operated as Wafer Fabrication Manager with IR Sensor company Pyreos where he developed and commercialised the first thin film PZT IR sensor manufacturing line.

Neil is a chartered Engineer (CEng) and Scientist (CSci) and corporate member of the Institution of Chemical Engineers (MIChemE) and holds a BEng (Hons) in Chemical & Process Engineering from Strathclyde University.

Bio:

Sanya Mathura, REng, MLE

Founder, Strategic Reliability Solutions Ltd

Sanya Mathura is a highly accomplished professional in the field of engineering and reliability, with a proven track record of success in providing solutions to complex problems in various industries. She is currently the Managing Director of Strategic Reliability Solutions Ltd, a leading consulting firm that specializes in helping clients improve their asset reliability and maintenance practices.

Sanya holds a Bachelor's degree in Electrical & Computer Engineering as well as a Masters in Engineering Asset Management from The University of the West Indies and has over 15 years of experience in the industry. She has worked with several well-known companies and has been recognized for her exceptional work in the field of reliability and lubrication engineering. Her expertise in developing and implementing asset management strategies, risk assessments, and root cause analysis has earned her a reputation as a subject matter expert.

As the head of Strategic Reliability Solutions Ltd, Sanya leads a team of highly skilled professionals who provide a wide range of services to clients across various industries, including oil and gas, manufacturing, and transportation. Under her leadership, the company has expanded its services and is now recognized as a leading provider of reliability engineering services in the industry across the globe.

In addition to her work at Strategic Reliability Solutions Ltd, Sanya is an active member of several professional organizations, including the International Council for Machinery Lubrication and writes technical papers for several organizations. She is also a sought-after speaker and has presented at various conferences and seminars on the topics of reliability engineering and lubrication. She is also an avid advocate for women in STEM.

Find out more in the article featured on Engineering Maintenance Solutions Magazine.

Used Oil Analysis

Emerging technology – FluidInspectIR®

By Sanya Mathura (Strategic Reliability Solutions Ltd) & Neil Conway (Spectrolytic)

Spectrolytic’s FluidInspectIR-Inline is a comprehensive fluid monitoring system that uses an array of sensors (MIR, OPC, wear, viscometer, conductivity) to provide real time data on oil and fluid degradation parameters. At the heart of the system is a novel mid-infrared (MIR) sensor that measures the chemical composition of the fluid with parameters such as; TAN, TBN, ipH, oxidation, sulphation, nitration, water, glycol, soot, fuel dilution and additives. These can be measured, as a first in the field, with the same accuracy and in the same units as conventional labs.

There are a couple of areas where the FluidInspectIR can offer advantages as compared to traditional oil analysis. Here are a few of them:

Real Time Monitoring and Faster Results – with these online monitoring devices, users can readily get data throughout the day without waiting for the sample to be taken, shipped to a laboratory and then tested there. This significantly reduces the time between making decisions which could negatively impact the equipment’s performance. Within our industry, this time is absolutely critical as the cost of unplanned downtime for the affected assets can be millions of dollars.

Cost-Effectiveness – every time a sample is taken, there is a cost involved. The sample taking process is usually quite lengthy as often permissions have to be obtained since more organisations are trying to reduce potential health & safety risks by minimizing human-machine interactions.
Once a sample has been obtained it needs to be shipped to a laboratory. This not only has costs attached to it, but many couriers are now making it very difficult to ship oil samples. In addition, each shipment of a sample carries also an implied CO₂ footprint.

Figure 1: Comparison of different routes of oil sampling

As shown in figure 1 the resulting cost savings from utilizing real time inline sensors compared to other methods can be summarized as follows:

Human assets can be utilized more effectively without allocating time for them to take oil samples
Trend analysis based on real time; laboratory equivalent data allows the end customer to move from a time-based maintenance process to a data driven maintenance process
Early failures can be spotted very easily and unplanned down time, the nightmare of every asset manager, can be minimized
Oil drain intervals can be extended in a safe and controlled manner which can result in significant operational efficiency gains and reduced CO₂ footprint

Accuracy and Reliability – getting an accurate representative sample using conventional oil sampling methods can be challenging at times. If the sample is taken at the wrong point (right after the filter or at a dead leg), it might not be representative of what is happening on the inside of the equipment. As such, it can completely derail the trend being established for that component and allow the users to believe that something is terribly wrong with that component.

With the FluidinspectIR online monitoring system, the sample delivery to the sensor is automated and standardized ensuring that the sample is delivered to the sensor in the correct way every time. Therefore, the users can rest assured of getting the sample taken at the right location (ensuring a proper representation of the system), at the same location (ensuring an accurate trend of the data) and with the same technique (which completely avoids any variation from human operators).

As the FluidInspectIR uses mid-infrared spectroscopy which is identical to the technique used by laboratories (FTIR), the data provided by the FluidInspectIR system has, at least, the same accuracy as those produced by a laboratory as shown in figure 2 below.

Figure 2: Comparison of the FluidInspectIR technology to periodic oil checks using a laboratory (red circles)

Actionable data and improved maintenance – with real time data, failures can be prevented and major unplanned downtime eliminated. With the online monitoring system, it is easier to trend an increase in wear metals, change in viscosity, water ingress or any other parameter changes which would warrant some form of maintenance intervention. This provides users with the information they need at the right time without any further delays due to shipping of samples or an inaccurate sample being sent off as shown in the case study in figure 3 where a diesel engine on a dredging vessel saw spiked concentrations of water that coincided with the vessel being moored in harbour. With the quick action of the inline sensors, they were able to save £115k over 9 months.

Figure 3: Case Study for Diesel engine customer

Data Integration and Remote Monitoring – traditionally, oil analysis results lived in databases which could be accessed electronically, or they were emailed and stored in a filing system. But these results are only available after a sample has been taken and sent off to the lab. This is how FluidInspectIR takes it a step further where assets can also be monitored remotely, in real time.

Imagine being able to monitor the conditions of a particular component while being offsite or multiple components for various sites. This can be particularly useful when trying to troubleshoot an issue related to a system process, especially across sites. This is one area that traditional oil analysis would not be able to mimic as the sample may not be taken at the exact same time as the ongoing system process therefore not allowing a correlation.

Of particular importance is the ability to trend data across multiple assets. This can be critical if there is a significant environmental factor influencing the condition of the oil which may affect many of the components in the fleet. Being able to easily and quickly detect this can be the difference between a productive day and one that has gone into unplanned downtime.

Find out more in the article featured on Engineering Maintenance Solutions Magazine.

Used Oil Analysis

Revolutionizing oil analysis: Traditional vs Cutting edge technology

By Sanya Mathura (Strategic Reliability Solutions Ltd) & Neil Conway (Spectrolytic)

In our last article we focused on the question of whether oil analysis was still relevant today? While this is an age-old process, the benefits of oil analysis still continue to live on today although the methods involved have significantly evolved since its inception. In this article, we will do a deeper dive into the traditional methods of oil analysis versus some of the new cutting-edge technologies which exist today and whether we may see a replacement of one method over the other or a union moving forward.

If you’ve ever performed an oil analysis you know that this process follows certain standards which are listed in the report. These standards govern the world of oil analysis and form the basis of how these tests are executed. There are committees dedicated to revising these standards to ensure that they are still relevant to the applications of today, one such committee falls under the ASTM body (American Society for testing and Materials).

Revolutionizing oil analysis Traditional vs Cutting edge technology

Equipment has changed over time where oil sumps have become smaller but now produce more power. Oils are under more stress as they are expected to perform at higher temperatures under elevated environmental conditions and still protect the equipment. Global oil manufacturers work together with OEMs (Original Equipment Manufacturers) to ensure that the oils developed can work with their components in these increasingly harsher conditions. But what constitutes an oil “working properly”?

This is where oil analysis / sample testing plays a crucial role. Oil analysis tests have been standardized through authorized committees to ensure that the same test can be performed in different parts of the globe using the same procedures. This ensures that there can be a fair comparison of the results of these tests across the globe. These tests should also be repeatable (or get the same results every time they are performed).

Typically, these tests are usually carried out in a laboratory environment, using state of the art equipment to achieve / maintain the required standards. However, sample taking, sample shipping and other human factors often result in misleading and / or extremely delayed reporting of the results. This is where emergent technology can alleviate some of these challenges.

Find out more in the article featured on Engineering Maintenance Solutions Magazine.

Storage & Handling of Lubricants

How Do We Prevent Contamination?

Contamination exists all around us, but we must prevent its intrusion into our lubrication systems to help keep our machines alive for a longer period. Some simple steps can be performed to help reduce levels of contamination. Also, lab tests can identify the presence of contaminants.

Storage & Handling

Unfortunately, this is the area in which many of the contaminants enter the lubricant. There is no discrimination in this area because all solids, liquids and gases can easily contaminate the lubricant.

Some best practices to follow are to first ensure that all lubricants are properly labeled and that everyone on the team knows the different uses for each lubricant. While this may seem simple, some people think that “oil is oil,” and any oil can work. Educating them on the differences and their effects of being mixed is critical to ensuring that they don’t get mixed up (or used as a contaminant to another lubricant).

Typically, with construction equipment, a lot of smaller sumps do not require a full pail of oil or may require an odd volume of oil. This often means that new unused oil either remains in the original packaging or is transferred to a holding container. If the new oil remains in the original packaging the user should ensure that the packaging remains sealed after use; is airtight (not to allow any other particles in); and stored in a cool, dry place.

If it is decanted into another container, this container needs to be:

Clean (not previously used for another oil, not “cleaned” using fuel or some other substance)
Properly capped (to prevent any contaminants from entering)
Kept in a cool, dry place

Filtration

While this may seem trivial, lots of users assume that their new lubricants meet the required cleanliness standards for their machines. This is not true. New lubricants can be dirty and should be filtered before use. The filtration specification will vary depending on the cleanliness required for your machine.

For instance, the cleanliness specification for a hydraulic machine will be different from that of the engine oil specifications because hydraulics have closer clearances. Although many machines contain system filters which will also catch some of the contaminants, it is always a best practice to filter all lubricants before placing them in your system.

Oil Analysis

Oil analysis is not a likely method to prevent contamination, but it can inform end users of the presence of contaminants. Because of this benefit, it should be used to monitor the level of contaminants in a lubricant and trend their increase or decrease over time. This can spot whether a leak in the system, if a correlation between wear and contaminants exists or an anomaly is present in the system.

The tests that should be used to identify the presence of contaminants include:

Viscosity (to determine if there is change in this value)
Fourier transform infrared spectroscopy
Elemental (to identify wear metals, additives and contaminants)
Karl Fischer or crackle for the presence of water or fuel

Elemental analysis can easily help identify the presence of wear metals or contaminants, but it can also identify the presence of additives that are not representative of the oil in use. This is a good way of identifying the presence of an incorrect lubricant or solution that may have been used during a top up for that component.

Example

A mixed fleet operator began noticing that the jobs allocated to the excavation crew were taking twice as long as usual, and the costs associated with those jobs for materials also increased. He decided to tag along with the site manager for one of these projects to understand the escalation of the hours and costs.

At the site, the project began smoothly and ran as it should for the first two weeks. Afterwards, he noticed that the equipment began experiencing some downtime on the site. Typically, this occurred on the day after the site maintenance crew carried out their lubricant top ups.

The lubricants were being stored in the elements close to a makeshift shed that held some other necessary tools. The maintenance crew did not have smaller containers to decant the oils for the hydraulic equipment, so they used their disposed soda bottles to “help.” Any lubricant that remained in the bottle was left open to the atmosphere, and then this was topped up by the new lubricant.

Unknowingly, these users were contaminating their oil before placing it in the machines. This led to the unplanned downtime and extra resources, such as more oil, filters and hours for the mechanic. Immediately, proper storage and decanting containers were purchased. The onsite staff was trained in using these containers, which were also color coded to avoid the mixing of different lubricants.

The allocated time for these jobs returned to normal. In addition, the costs associated with the materials decreased because they no longer had to purchase extra oil to make those oil changes when the equipment shutdown.

Contamination can have a significant impact on the downtime of your equipment but can be easily prevented by using proper storage and handling techniques and monitoring the presence/absence of particles through oil analysis.

References

SKF, (June 6, 2024). Solutions for Contamination. Retrieved from SKF: https://www.skf.com/group/industries/mining-mineral-processing-cement/insights/solutions-for-contamination.

Find out more in the article in Equipment Today Magazine.

Storage & Handling of Lubricants

Is Oil Contamination Affecting the Performance of Your Equipment?

Often, the particles we don’t see are the ones that affect us most. For instance, we can’t see bacteria or germs but those can easily get into our body and make us sick. Something similar occurs with our equipment and the lubricants which are used to help them work more efficiently. SKF notes that contamination and ineffective lubrication are responsible for 51% of bearing, coupling, chain and other machine component failures in equipment.

Logically, if we control the amount of contamination, we can control the number of failures and all the resulting consequences, such as unscheduled downtime and rush expenses (for called out or specialized labor and parts). In this column, we explore how contamination can impact the performance of your equipment, ways to combat contamination and some examples.

Is Oil Contamination Affecting the Performance of Your Equipment

What Is Contamination?

Contamination is anything that is foreign to the environment. For machinery lubricants, these are usually classified in three main groups: Gases, liquids and solids. When speaking about gases, this can be air or other gases (such as ammonia or methane) that encounter the lubricant. For liquids, this includes water, fuel or any other liquid that can enter the lubricant, particularly other lubricants or liquids that can be added knowingly or unknowingly. Lastly, solids can mean dirt (from outside the process), metals (from inside the machine) or any other solid particle in the lubricant.

Gases

Gases are the most unsuspected forms of contamination since many people believe that a gas will not affect the lubricant or by extension the machine. However, if air gets trapped in a closed loop system, this can lead to foaming (if the oil makes its way to the surface) or to microdieseling if it remains entrained in the oil.

With foaming, this typically occurs in gearboxes or equipment that are subjected to high churn rates of oil. Foam can settle at the top of the oil and cause the lubricant to not form a full film to separate the contacting surfaces. As such, this can lead to wear of the equipment.

On the other hand, microdieseling or the entrainment of air in the system can also prove to be dangerous because the trapped air bubbles can give rise to temperatures in excess of 1,000°C if they move between different pressure zones. This will lead to oil degradation, often producing some coke or tar insoluble as final deposits. Additionally, this trapped air/gas can also advance to cavitation inside the equipment.

Additionally, if the gas trapped is not air but a catalyst to a chemical reaction, this can incite further or more rapid degradation of the oil making it no longer able to protect the equipment. Therefore, identifying the presence of unwanted gases in your lube oil systems or preventing their entry in the first place is important.

Liquids

Liquids are trickier than gases because they somehow seem to enter the lubricant more easily or get mixed in unknowingly. When a liquid enters a lubricant, it can directly impact the viscosity of the lubricant, either increasing it or decreasing it. In either of these cases, this can be detrimental to the equipment.

If the lubricant’s viscosity increases above the essential value, then the machine will demand more energy to execute its required functions. This will directly impact its efficiency and energy consumption. On the other hand, if the lubricant’s viscosity decreases outside of the essential value, then the lubricant may not be able to adequately protect the contacting surfaces. Therefore, this increases the amount of wear that may occur on the inside of the machine.

Typically, water and fuel are the most common culprits of liquid contamination. These can easily get into your lubricants through poor storage and handling practices. Water can increase the viscosity of your lubricant and cause some additives to drop out of it, reducing its level of protection. Fuel will decrease the viscosity and possibly add to the fire risk of the system. Both can severely damage your equipment.

Another common culprit is the mixing of different types of oil. On an average day, things are busy, and people can get confused and pick up the wrong oil to perform a top up on a system. If we add gear oil or hydraulic oil to an engine oil system, we can have a catastrophe! These oils would have different viscosities, and their additive packages (or even base oils) may not be compatible. This can cause the equipment to stop working, leading to unplanned downtime and then exorbitant resources to get the machine operating again.

Solids

Solids can easily get into our equipment either from the outside or the inside. If there are openings to allow solids to enter then they will. However, sometimes solids enter our lubrication systems without us knowing. This can happen through poor storage and handling practices.

Once solids enter the system, they can:

Increase the viscosity of the oil
Increase the amount of wear occurring inside the equipment
Act as a catalyst (depending on their nature)
Block smaller clearances causing unwanted downtime in the equipment

Typically, solids are usually dirt, which can enter from outside the equipment. However, these hard particles can cause some metal to be damaged on the inside the equipment which can then lead to the metal being a catalyst for another degradation mode.

Some solids are formed inside the equipment as deposits. These deposits can occur if another contaminant (liquid, gas or another solid) enters the system and reacts with the oil to produce them. As such, these deposits may clog injectors, other valves or tight clearances causing the equipment to malfunction.

Find out more information in the article in the Equipment Today Magazine.