Oil Properties Archives - Page 5 of 8 - Strategic Reliability Solutions Ltd

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 in the full article, "Are Hydraulic oils the most Powerful oils?" featured in Equipment Today Magazine by Sanya Mathura, CEO & Founder of Strategic Reliability Solutions Ltd.

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 in the full article, "Are Hydraulic oils the most Powerful oils?" featured in Equipment Today Magazine by Sanya Mathura, CEO & Founder of Strategic Reliability Solutions Ltd.

Oil Properties

What Are The Functions of Hydraulic Oils?

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.

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 in the full article, "Are Hydraulic oils the most Powerful oils?" featured in Equipment Today Magazine by Sanya Mathura, CEO & Founder of Strategic Reliability Solutions Ltd.

Oil Properties

The Future of Gear Oils

According to (Industry ARC (Analytics. Research. Consulting), 2024), the global industrial gear oil market size is forecasted to reach USD 5.2 B by 2027. While the Asia-Pacific market holds a significant market share for industrial gear oils in 2021 at around 56.2%, it is interesting that its nearest rival is Europe, at 17.7% or less than ⅓ of its size.

The rise in the Asia Pacific market can be accounted for due to the increase in the rising population and, by extension, the needs of that population and the service sectors they support, including the energy, oil & gas, construction, and steel industries. The figure below depicts the global industrial gear oil market revenue share by Geography for 2021.

Figure 6: Industrial Gear Oils (Mineral & Synthetic) Market Revenue Share by Geography 2021 adapted from (Industry ARC (Analytics. Research. Consulting), 2024)

From the research conducted by (Industry ARC (Analytics. Research. Consulting), 2024), helical gears appear to be the most popular choice for industrial gears. Interestingly enough, synthetic gear oil held the largest market share and is forecasted to grow by a CAGR of 5.6% for the forecasted period of 2022-2027.

Smaller gearboxes are being manufactured, tasked with outperforming their previous counterparts and producing more torque in a smaller space. With the advent of better, more precise machining tools for gears, there is an increase in the amount of pressure these gears now must handle in smaller spaces.

As such, we will continue to see the rise in the use of synthetic gear lubricants formulated to handle these extreme conditions, as well as more advanced additive packages that can help minimize foaming, reduce oxidation, and aid in the demulsibility of these oils.

References

Industry ARC (Analytics. Research. Consulting). (2024, September 04). Industrial Gear Oils (Mineral & Synthetic) Market - Forecast(2024 - 2030). Retrieved from Industry ARC: https://www.industryarc.com/Report/20008/industrial-gear-oils-mineral-and-synthetic-market.html

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

Mang, T., Bobzin, K., & Bartels, T. (2011). Industrial Tribology - Tribosystems, Friction, Wear and Surface Engineering, Lubrication. Weinheim: WILEY-VCH Verlag GmbH & Co. KGaA.

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

Rensselar, J. v. (February 2013). Gear oils. Tribology and Lubrication Technology - STLE, 33.

Sander, J. (2020). Putting the simple back into viscosity. Retrieved from Lubrication Engineers: https://lelubricants.com/wp-content/uploads/pdf/news/White%20Papers/simple_viscosity.pdf

Santora, M. (2018, March 20). Tips on properly specifying gear oil. Retrieved from Design World: https://www.designworldonline.com/tips-on-properly-specifying-gear-oil/#:~:text=CLP%20Gear%20Oils&text=Often%2C%20a%20gear%20manufacturer%20will,a%20CLP%20polyglycol%20PAG%20oil

Find out more in the full article, "Gear Oil: Types, Applications, and Benefits" featured in Precision Lubrication Magazine by Sanya Mathura, CEO & Founder of Strategic Reliability Solutions Ltd.

Oil Properties

Gear Oil Storage and Handling

Similar to most oils, gear oils should be stored in a clean and dry space. Often (especially in the past), these gear oils see a settling of the additives to the bottom of the container, indicating a slightly shorter oil life span than other lubricants. However, this is no longer a highly occurring incident with the advancements in additive technology and improved blending practices.

As usual, it is always best to adhere to the OEM’s expiry dates for these products, as different OEMs recommend varying storage times for their products. Generally, synthetic lubricants have an estimated shelf life of 5-10 years, while mineral oils usually last for around 2-3 years, but this is heavily dependent on the OEM and storage conditions.

In some cases, customers tend to store these drums outside in the elements as it makes it easier for them to be readily accessible for decanting into the equipment. However, in these environments, the drums can collect water, which will enter the oil and then, by extension, enter the gearbox. This can cause issues for the equipment and lead to accelerated oil degradation.

Ideally, these oils should be stored in a cool, dry place with ready access to decanting equipment where the decanted oil will not be easily contaminated. Many industrial gearboxes typically require larger quantities of oil, and decanting can take place directly from the drum into the equipment or via a pump.

In these cases, the level of contamination must be minimized by ensuring that the fittings, hoses, etc., are clean and have not been used to decant other types of oils.

Find out more in the full article, "Gear Oil: Types, Applications, and Benefits" featured in Precision Lubrication Magazine by Sanya Mathura, CEO & Founder of Strategic Reliability Solutions Ltd.

Oil Properties

How do Gear Oils Degrade?

The first set of additives to decrease in gear oils is often the antiwear or extreme pressure additives. This is no surprise, as these oils are subjected to high levels of wear and must withstand extreme pressures. One can also notice a decline in the rust and oxidation additives or even a change in the air release values.

All these properties significantly impact how a gear oil functions. As such, they should be monitored when establishing the health of the oil.

When monitoring the health of these lubricants, some guidelines can be utilized. If there is a change in viscosity of either ±10%, one should look for any other correlating changes.

Typically, if the viscosity increases by 10%, we’re looking at increases in wear metals or the risk of oxidation and development of some deposits in the oil or even contamination of the oil with some water. However, for a decline of 10%, one can expect some form of contamination, typically fuel or another substance which will thin out the lubricant.

The lubricant’s warning levels for wear metals will vary depending on the manufacturer/OEM. However, any consistent rise in wear metals indicates that some component on the inside of the equipment is slowly wearing away.

Find out more in the full article, "Gear Oil: Types, Applications, and Benefits" featured in Precision Lubrication Magazine by Sanya Mathura, CEO & Founder of Strategic Reliability Solutions Ltd.

Oil Properties

Gear Oil Characteristics and Naming Systems

From the information covered thus far, we can appreciate that gear oils need to accommodate many changes to their environment. A few characteristics stand out when looking at industrial gear oils (Mang, Bobzin, & Bartels, Industrial Tribology—Tribosystems, Friction, Wear and Surface Engineering, Lubrication, 2011).

These include viscosity-temperature, Fluid Shear Stability, Corrosion and Rust Protection, Oxidation Stability, Demulsibility and Water Separation, Air release, Paint Compatibility, Seal Compatibility, Foaming, Environmental, and Skin Compatibility.

Gear Oil Characteristics and Naming Systems

Depending on where you are in the world, you may use a different system to classify gear oils. The ISO Viscosity grade system is used internationally, but the AGMA (American Gear Manufacturer’s Association) system is used in the Americas and some parts of Asia. A chart can be used to move that across these grading systems, as shown below in Figure 5.

Figure 5: Various gear oil grading systems as adopted from (Sander, 2020)

As per (Sander, 2020), the AGMA numbers have some particular meanings as stated:

No additional letters (only a number) – Contains only R&O additives
EP – Mineral oil with Extreme Pressure additives
S – Synthetic gear oil
Comp – Compounded gear oil (3-10% fatty or synthetic fatty oils)
R – Residual compounds called diluent solvents which reduce the viscosity to make it easier to apply

Another rating that is seen a lot is the CLP rating. This is a German oil standard defined by ASTM DIN 51517-3, in which the test requirements to meet the CLP specification are documented.

This DIN standard covers petroleum-based gear lubricants with additives designed to improve rust protection, oxidation resistance, and EP protection. Some typical classifications seen are CLP-M (which represents mineral gear oil), CLP HC (which represents synthetic oils [SHC, PAO, POE]), and CLP PG (which represents polyglycol PAGs), according to (Santora, 2018).

There are three main DIN 51517 classifications as per (Rensselar February 2013), namely;

DIN 51517 CGLP – contains additives that protect from corrosion, oxidation, and wear at the mixed friction spots and additives that improve the characteristics of sliding surfaces
DIN51517-3 CLP – contains additives that protect against corrosion, oxidation, and wear in the mixed friction zone
DIN 51517-2 CL – contains additives that protect against corrosion and oxidation suitable for average load conditions

The above are some of the more prevalent naming systems for industrial gear oils, and they are found on most gear oils globally.

Find out more in the full article, "Gear Oil: Types, Applications, and Benefits" featured in Precision Lubrication Magazine by Sanya Mathura, CEO & Founder of Strategic Reliability Solutions Ltd.

Oil Properties

Is there more than one type of gear?

Gears are used in all aspects of life, from bicycles to tiny watch gears, car transmissions, and even highly specialized surgical equipment. Gears keep the world moving. However, when they move, they often rub against each other, and if this friction is not managed, it can cause wear and eventually lead to significant damage or failure. This is where gear oil makes a difference.

In this article, we will explore the various types of gear lubricants, their composition, how they degrade, some storage and handling tips, and what the future holds for these types of oils.

Figure 1: Different types of gears according to (Mang & Dresel, Lubricants and Lubrication – Second Edition, 2007) Chapter 10

If you’re familiar with gears, you know that despite the standard emoji keyboard, more than one type of gear exists. There are several types of gears, each suited for various applications. As such, each application will have varying environmental conditions, which will require specialized lubricants to reduce friction and wear.

One of the main operational conditions for gears is the transfer of torque. Even when torque is transferred, gears will have sliding and rolling contact, leading to frictional losses and heat generation. Therefore, the lubricants selected for these applications must be able to significantly reduce these frictional losses and cool the gears.

As per (Pirro, Webster, & Daschner, 2016), several types of gears can be classed into three groups based on the interaction of the teeth of these gears and the types of fluid films formed between the areas of contact:

Spur, Bevel, Helical, Herringbone, and spiral bevel
Worm gears and
Hypoid gears

Figure 1 shows some of the types of gears which exist.

It must be noted that hypoid gears transmit motion between nonintersecting shafts at a right angle. Additionally, there is a difference between rolling and sliding.

Rolling indicates continuous movement, whereas sliding varies from a maximum velocity in one direction at the start of the mesh through zero velocity at the pitch line and then back to maximum velocity in the opposite direction at the end of the mesh, as seen in Figure 2.

According to Mang, Bobzin, and Bartels (Industrial Tribology—Tribosystems, Friction, Wear and Surface Engineering, Lubrication, 2011), hypoid gears require heavily loaded lubricants. These should have high oxidation stability, good scuffing, scoring, and wear capacity, as the tooth contacts have a high load.

The lubricant must also have a high viscosity at operating temperature such that the formed film can sufficiently support the load while cooling the gears.

Conversely, hydrodynamic gears such as torque converters, hydrodynamic wet clutches, or retarders require high oxidation stability characteristics but do not need good scuffing or scoring load capacity characteristics. Unlike hypoid gears, hydrodynamic gears experience viscosity-dependent losses, so they must have a lower viscosity at operating temperature.

Figure 2: Meshing of involute gear teeth. These photographs show the progression of rolling and sliding as a pair of involute gear teeth (a commonly used design) pass through mesh. The amount of sliding can be seen from the relative positions of the numbered marks on the teeth adapted from (Pirro, Webster, & Daschner, 2016), Chapter 8.

According to (Mang & Dresel, Lubricants and Lubrication – Second Edition, 2007), there are some frequent failure criteria for gears and transmissions, including:

Extreme abrasive wear
Early endurance failure, fatigue of components in the form of micropitting and pitting
Scuffing and scoring of the friction contact areas

Continuous abrasive wear is usually observed at low circumferential speeds and during mixed and boundary lubrication. Typically, continued wear can cause damage that extends to the middle sector of the tooth flank. Understandably, lubricants with a high viscosity and a balanced quantity of antiwear additives promote a higher tolerance to wear.

Micropitting can be observed on tooth flanks at all speed ranges. Those with rough surfaces are prime candidates for micropitting. Typically, this develops in negative sliding velocities or the slip area below the pitch circle.

Usually, microscopic, minor fatigue fractures occur first, which can lead to further follow-up damage such as pitting, wear, or even tooth fractures. A lubricant with a sufficiently high viscosity and a suitable additive system can help reduce this type of fatigue.

At predominantly high or medium circumferential speeds, scuffing and scoring of the tooth flanks occur, and the contacting surfaces can weld together for a short time. Due to the high sliding velocity, this weld usually breaks, causing scuffing and scoring.

Typically, this damage is seen on the corresponding flank areas at the tooth tip and root, which experience high sliding velocity. In this case, lubricants with higher EP (Extreme Pressure) additives can help reduce this damage.

According to (Ludwig Jr & McGuire, March 2019), the type of gear can aid in determining the most appropriate industrial gear oil. The following table is an adaptation from the article:

Table 1: Gear type and appropriate lubricant adapted from (Ludwig Jr & McGuire, March 2019)

As per (Mang & Dresel, Lubricants and Lubrication – Second Edition, 2007), transmission gears can be broken down into two main types: those with a constant gear ratio and those with a variable gear ratio. These can be seen in Figures 3 and 4 below.

Figure 3: Gears with a constant gear ratio adapted from (Mang & Dresel, Lubricants and Lubrication – Second Edition, 2007), Chapter 10

Figure 4: Gears with a variable gear ratio adapted from (Mang & Dresel, Lubricants and Lubrication – Second Edition, 2007), Chapter 10

Find out more in the full article, "Gear Oil: Types, Applications, and Benefits" featured in Precision Lubrication Magazine by Sanya Mathura, CEO & Founder of Strategic Reliability Solutions Ltd.

Oil Properties / Used Oil Analysis

Is Oil analysis still relevant today?

With the many advancements in Artificial Intelligence, Machine Learning and the advent of countless different sensors on the market, the question arises, “Is Oil Analysis still relevant today?”. Granted that these advancements have significantly transformed the industry, we need to recognize that they are here to help evolve what we already do and not necessary replace it.

These advancements build upon the foundations of the techniques of oil analysis. With artificial intelligence and machine learning, we can train models to interpret oil analysis data and trigger alerts accordingly but there should always be a human present to overview these. In the real world, not every situation has occurred or been recorded yet hence the models do not have that particular data to learn from nor can they make decisions about it since it simply doesn’t exist in their “brain”.

Humans can “think outside the box” and formulate patterns or trends which may not be triggered by the models simply because these models have not been taught these patterns. Hence it is important to always have a human in the loop and not rely solely on these models especially when million-dollar decisions can be negatively initiated with the wrong interpretations.

Lately, sensors have gained more traction and a wider adoption as they can be integrated into warning systems to alert users to potential deviation from known characteristics of the oil. However, as noted above, sensors rely on data sets to compare the information and on some form of capacitance which must be converted into a signal before it can be interpreted.

With lab equipment performing the actual tests, there is a higher rate of accuracy plus the added advantage of having humans review the results for discrepancies before sending off the report. While sensors can be the first warning system for some users, lab equipment should be utilized for those more precise tests which require a higher level of accuracy.

In essence, oil analysis remains very relevant today. However, it has significantly evolved over the last few decades. Today, oil analysis can achieve a higher efficiency level with the integration of the advancements in technology (AI, machine learning and sensors) and other available monitoring technologies. Together, these should all be used to create a greater impact on improving the reliability of the machines.

Find out more in the full article, "Is oil analysis necessary with so many other technologies available?" featured in Engineering Maintenance Solutions Magazine by Sanya Mathura, CEO & Founder of Strategic Reliability Solutions Ltd.

Oil Properties / Used Oil Analysis

Oil analysis vs Other technologies

Just as oil analysis is similar to blood testing, we can think of our bodies as a critical machine with various components which need to be monitored. If we get a fractured bone, a blood test will not help us to assess if the bone is broken or can be repaired. In this case, we may need an x-ray. Similarly, with machines, there are various types of tests to determine different aspects to be monitored.

Typically, oil analysis can provide the operator with insight into whether there has been any internal damage to the equipment in the form of wear particles which can be quantified. As with most condition monitoring methods, being able to trend the patterns over time helps the operators to identify if wear is occurring at an increased rate or whether the oil is degrading.

On the other hand, other technologies such as vibration analysis or ultrasound analysis or even thermography are not able to detect the presence of molecules. These other types of analyses focus on alignment, or other mechanical issues as they occur and can trend them over time. However, oil analysis can accurately detect the presence or absence of contaminants or additive packages which could affect the health of the oil and by extension that of the machine.

Oil analysis should not be used as the only technology in your condition monitoring artillery. Other technologies can be used alongside oil analysis to provide the user with a more comprehensive overview of the health of the asset. For instance, if the oil analysis discovered high wear, the next step would be to identify where the wear was coming from. Perhaps in this case, one of the other technologies could identify a misalignment or other mechanical issue which could be the source of this wear. Thus, these technologies should be used to work together to achieve better reliability for their asset owners.

Find out more in the full article, "Is oil analysis necessary with so many other technologies available?" featured in Engineering Maintenance Solutions Magazine by Sanya Mathura, CEO & Founder of Strategic Reliability Solutions Ltd.

Category: Oil Properties

What Are The Functions of Hydraulic Oils?

References