Mixing viscosities

Can I mix different viscosities of oils to get the viscosity that I want?

It can be done but this is not an ideal situation.

There are times when the only available viscosity is an ISO 46 (on a rig) but the equipment requires an ISO 68 and the new stock will not be delivered in time to avoid shutdown. Can the ISO 46 be used instead?

An ISO 46 oil is lighter in viscosity than an ISO 68 however, for most oils, there is a chart that depicts the viscosity of the oil at operating temperature. In these cases, one can consult this chart and determine if the viscosity at operating temperature will still fall within operating limits.

If we mix an ISO 46 with an ISO 68 oil we cannot be certain of where the new viscosity will fall especially if we do not know the ratios that are being used. There is a viscosity calculator that can help guide this decision available at: https://www.widman.biz/English/Calculators/Mixtures.html

This can be used as a guide and the actual values of the oil should be verified via oil analysis.

While this situation is not ideal, we need to remember that compatibility is also key.

As such, we should stick with the same line of lubricants that we being used. Typically, lubricant suppliers have the same formulation but change the viscosities for lubricants of the same line.

Automotive / Strategic Tips

TBN decrease

The TBN has dropped significantly, can I still use the oil?

The TBN (Total Base Number) is usually seen in diesel engines. Most modern (smaller) diesel engines have TBNs within the range of 9-15 (especially if they are using ULSD).

The TBN gets depleted when the acids in the oil start to increase.

Typically, higher sulphur levels in the fuel produce more acids. As such, as the sulphur level increases, so does the TBN level.

For instance, in power plants that use larger (older) diesel engines that require HSFO (High Sulphur Fuel Oil, 3.5% sulphur), the TBN of the lubricant can be as much as 50. Here are the different types of fuel and their sulphur ratings:

HFSO (High Sulphur Fuel Oil): 3.5%
LSFO (Low Sulphur Fuel Oil): 1.0%
ULSFO (Ultra Low Sulphur Fuel Oil): 0.1%

With IMO 2020, the cap has been placed on sulphur in fuel to 0.5% for marine vessels. While this cap has not yet been translated to land applications, due to the demand for HSFO declining there may be a shift to ULSFO in land based applications in the not so distant future.

Ideally, if your TBN level gets depleted by 50% then there is a cause for concern and the oil should be changed or topped up with new oil (depending on which is more convenient).

If your TBN levels get to 50% in a very short time, you may want to investigate the reasons behind the value dropping so significantly in such a short time (perhaps fuel dilution or thermal cracking?).

Always investigate the reasons behind unexpected results as these will continue to impact your lubricant in the future.

Automotive / Strategic Tips

Mixing oils

Can I mix hydraulic oils with engine oils?

Oils should never be mixed!

Every oil is designed with its application in mind. As such, they are blended with varying concentrations and types of additives. For instance, a typical engine oil has at least 30% additives while a turbine oil may have only 1% additive.

Hydraulic oils are designed for applications where power has to be transmitted through the lubricant. On the other hand, engine oils are designed to withstand varying temperatures (gasoline engines have a different temperature range compared to diesel engines. Diesel engines generally run at higher temperatures than gasoline engines).

Always pay particular attention to what the OEM recommends. Usually, the OEM will recommend that a lubricant meets a particular global standard (API SN or CK4). These standards were developed to ensure the best performance of an engine and should be adhered to when choosing lubricants.

Automotive / Strategic Tips

Multigrade vs Monograde

Why use multigrade instead of monograde oils?

A monograde oil does not provide the same level of protection on start-up as a multigrade oil.

With the multigrade oil, it is designed to reduce the time it takes to get from the bottom of the sump to the top of the engine (this is indicated by the number in front of the “w”).

However, the monograde oils have not been adapted for this type of technology. Thus, it takes longer to get to the top of the engine and to all the components compared to a multigrade oil.

Most wear occurs on start-up. Before we start the car on a morning, all of the oil is at the bottom of the sump, so it takes some time to get to the top and the other components. However, once we start the engine, all the parts will begin moving. If they are moving without any lubrication, then a significant amount of wear will occur!

Typically, when driving, we start the car, go to our destination and stop. Then come back and start the car again. During this time, the oil would have drained back to the bottom of the sump and now has to get back to the top. Before it gets to the components, these are still moving without lubrication, inducing wear! If we think of the number of times that we start and stop for the day (or for the month!), we will realize the amount of wear that we put our engines through.

Hence, this is one of the main reasons, that we choose multigrades over monogrades.

Lubricant Degradation / Used Oil Analysis

Additives and their properties

Properties of Additives in Lubricants

Each lubricant has a varying percentage of additives as not all lubricants are created equally. Lubricants are designed based on their application or use within the industry. For instance, an engine oil is typically composed of 30% additives, 70% base oil while turbine oils comprise 1% additives and 99% base oil.

Therefore, particular attention must be paid to getting the additive compositions to be just right for the application and ensuring that the additives can perform their functions.

Each additive has a particular function and is used as per the application of the lubricant. We have adapted the following from Analysts Inc – Basic Oil Analysis which describes the purpose of some of the most commonly used additives in lubricants.

Lubricant Degradation / Reliability / Storage & Handling of Lubricants

ICML 55 – the revolution in the lubrication sector

What is ICML 55?

ICML 55 is revolutionizing the lubrication industry! It is so exciting to be around at this time when it has started its implementation. For those who aren’t aware of ICML 55, here are a couple of notes on it.

ICML 55 was born out of ISO 55000 which speaks to Asset Management. From this standard, 3 standards were developed to guide the lubrication industry since no previous standards existed within the lubrication industry.

ICML 55.1 - Requirements for the Optimized Lubrication of Mechanical Physical Assets
ICML 55.2 - Guideline for the Optimized Lubrication of Mechanical Physical Assets
ICML 55.3 - Auditors' Standard Practice and Policies Manual

ICML 55.1 has already been completed, while 55.2 should be done at the end of this year and 55.3 scheduled for 2020.

These are exciting times!

Here’s the official press release:

https://info.lubecouncil.org/2019/04/04/icml-introduces-icml-55-asset-management-standards-mle-engineer-certification/

While ICML 55.1 was only launched in April of this year (2019), it is a standard that the lubrication industry has been in need of for several years. It addresses the “Requirements for the Optimized Lubrication of Mechanical Physical Assets”.

What exactly are the assets covered? Here they are:

Rotating & Reciprocating Machines, Powertrains, Hydraulic Systems and lubricated subcomponents
Assets with lubricants that reduce friction, wear, corrosion, heat generation or facilitate transfer of energy
Finished products from API categories I-V
Non Machinery support assets (Personnel, policies, procedures, storage facilities and management)

There are also fluids and assets which are NOT covered:

Fuels, coolants, metal-working fluids, pastes, fogging agents, preservative fluids, coating materials, heat-transfer fluids, brake fluids, cosmetic lubricants
Solid lubricants (e.g., powders and surface treatments used as coating rather than to reduce friction between surfaces in motion)
Additives independent of the finished lubricant
Electrical transformer oils and anti-seize compounds
Fluids and materials derived from a petroleum or petroleum-like base
Fluids that do not serve a lubrication function

Photo Credit: https://info.lubecouncil.org/icml-55-standards/

ICML 55.1 speaks to the “Requirements for the Optimized Lubrication of Mechanical Physical Assets” it also describes and defines 12 interrelated areas that can be incorporated in a lubrication program. This has never been officially documented before, nor has any standard been published as a guideline for lubrication programs.

The 12 areas are outlined below:

SKILLS: Job Task, Training, and Competency
MACHINE: Machine Lubrication and Condition Monitoring Readiness
LUBRICANT: Lubricant System Design and Selection
LUBRICATION: Planned and Corrective Maintenance Tasks
TOOLS: Lubrication Support Facilities and Tools
INSPECTION: Machine and Lubricant Inspection
LUBRICANT ANALYSIS: Condition Monitoring and Lubrication Analysis
TROUBLESHOOT: Fault/Failure Troubleshooting and RCA
WASTE: Lubricant Waste Handling and Management
ENERGY: Energy Conservation and Environmental Impact
RECLAIM: Oil Reclamation and System Decontamination
MANAGEMENT: Program Management and Metrics

As per ICML's website, here's a list of people that the new standard can benefit:

Photo Credit: https://info.lubecouncil.org/icml-55-standards/

Check out the ICML 55 standards today and apply it to your organization!

Used Oil Analysis

Used Oil Analysis Tips

“When should an oil sample really be taken?”

In used oil analysis, oil samples can be taken at any time, but one should always consider the insight that they are trying to gain before testing the sample. This is crucial in deciding the type of tests and the intervals at which they should be performed.

For instance, if we are testing the quality of the oil or we want to compare a fresh batch to a used one, then we can take a sample directly from the drum.

If we are trying to decide the rate at which the additives are being depleted or wear being accumulated then we can take a sample at different operating hours to trend the data. This method can work if we are trying to determine the most appropriate run time for a lubricant in particular conditions.

However, if we are trying to track the health of the components on a regular basis as part of our PM program then taking a sample at the end of the scheduled maintenance interval is desired.

Taking an oil sample from a component is like performing a blood test by the doctor. It helps us to understand what’s really happening. It can show us if there is excessive wear, contamination or lubricant degradation which allows us to identify its “health”. However, the correct tests need to be carried out to determine these conditions.

There must be a reason behind taking the oil sample, not just a random act. When trying to establish a trend regarding a particular aspect of the oil, this should guide your choice of tests otherwise we can end up paying for tests that do not add value.

Always ensure sound reasoning behind testing rather than just checking the box!

While taking an oil sample at the end of the scheduled operating hours is very convenient, is it truly efficient?

When a piece of equipment is scheduled for maintenance, it is usually taken out of service for a couple of hours to perform the assigned
maintenance tasks.

However, if an oil sample is taken a couple days in advance of the scheduled maintenance, then when the results return the maintenance team can be on the lookout for issues highlighted by the results.

For instance, if the value for iron was significant or rising then they can perform inspections for areas which may cause this type of wear and address this challenge while the equipment is offline.

The graphic on the side can be used as a quick guide to determining when to take a sample.

Remember to always evaluate the reason behind establishing the sampling frequency before scheduling sampling.

Lubricant Degradation / Storage & Handling of Lubricants

Lubricant Deterioration Identifications

What the difference between Shelf Life and Service Life?

There’s a major difference between Shelf life and Service life especially when it concerns lubricants!

No one wants to put expired lubricants into their equipment! This can cause unexpected failures which can lead to unplanned downtime which can continue to spiral down the costly path of unproductivity!

Shelf Life

The Shelf life is usually what is stamped by the Manufacturer indicating the length of time the product can remain in its current packaging before being deemed unsuitable for use. These can typically be found on the packaging.

Service Life

The Service life however is determined by the application and conditions under which the lubricant is being used. Usually, estimated running hours / mileage are given by the equipment manufacturer in the maintenance section of the manual. (Condition monitoring can also be used to determine appropriate service intervals.)

However, how will someone know if the product has deteriorated while still in its original packaging? What should someone typically look for?

Above are some tips for identification of deterioration in lubricants. Take a note of these for the next time you are unsure of the integrity of your lubricants.

Lubricant Degradation / Storage & Handling of Lubricants

Conditions that affect lubricants

What conditions affect lubricants?

How are your lubricants currently stored?

Are you storing lubricants under the correct conditions?

These questions have come up a dozen times during audits and countless warehouse meetings!

To answer these questions, there are five main conditions that can affect lubricants. We have detailed them along with the effects of these conditions on the lubricant.

Temperature – if incorrect can lead to oxidation. For every 10C rise in temperature above 40C the life of the lubricant is halved.
Light – too much can lead to oxidation especially for light sensitive lubricants such as transformer oils. Hence the reason that most packaging is opaque.
Water – this usually works with additives to cause their depletion or contamination of the product. Water in any lubricant is bad (especially for transformer oils as they are involved in the conduction of electricity.
Particulate contamination – contamination can occur by air borne particles if packaging is left open or if dirty containers/vessels are used to transfer the lubricant from its packaging to the component.
Atmospheric contamination – this affects viscosity and promotes oxidation and can occur if packaging is left open. For instance, if a drum is not properly resealed or capped after usage or the most common practice of leaving the drum open with the drum pump on the inside.

Different types of lubricant degradation

Why is it important to know the types of lubricant degradation?

It’s important since it helps us to figure out why or in some instance how, the lubricant degraded! Usually degradation is the change that occurs when the lubricant can no longer execute its five main functions:

the reduction of friction
minimization of wear
distribution of heat
removal of contaminants and
improvement of efficiency.

Types of lubricant Degradation Mechanisms

There are 6 main types of Lubricant Degradation as detailed below. Each type produces various by products which can enable us to understand the reason for the degradation and eliminate that / those reasons.

Here are the 6 main types of Lubricant Degradation:

1. Oxidation
2. Thermal Breakdown
3. Microdieseling
4. Additive Depletion
5. Electrostatic Spark Discharge
6. Contamination

As discussed, each mechanism produces distinct results which help us in their identification! Check out our article on why lubricants fail for more info!

Lubricant Degradation / Used Oil Analysis

Oxidation

What is Oxidation?

One of the major types of oil degradation is Oxidation. But what is it exactly, as applied to a lubricant?

Oxidation is the addition of oxygen to the base oil of the lubricant to form either of the following:

Aldehydes
Ketones
Hydroperoxides
Carboxylic Acids

Wow… too many chemical names right?! These help to pinpoint the conditions responsible and then we can address them accordingly. Each of these by products are produced by different types of reactions or in some cases different stages of the oxidation process. It is key to note the type of by product as it gives us a clue to the root of the issue through which oxidation occurs.

For instance, the presence of Carboxylic acids can result in the formation of Primary Amides which can lead to heavy deposits. Early detection of the Carboxylic acids can help us prevent this. Once we determine the source of oxidation to produce the carboxylic acids, we can in turn remove this from the system.

Oxidation Stages

Oxidation does not happen in an instant. Usually, it follows a series of events which eventually lead to oxidation. Like any process in life, there are different stages for Oxidation:

Initiation – Production of the free radical via the lubricant and catalyst.
Propagation – Production of more free radicals via additional reactions
Termination – Continuation of oxidation process after the antioxidants have been depleted or the antioxidant stops the oxidation process.

Results of Oxidation

Why is Oxidation bad for the lubricant? What can it ultimately result in?

Well, oxidation can result in the formation or lead up to the following:

Varnish
Loss of antifoaming properties
Additive depletion
Base oil breakdown
Increase in viscosity
Sludge

None of these are good for the lubricant!!!!!!!!! If you see any of these signs be sure to test for oxidation and identify the root cause for the introduction of oxygen in your system.

Oxidation Tests

Now that we know more about oxidation… what tests can be performed to prevent it?

There are 6 main tests that can be performed:

RPVOT (Rotating Pressure Vessel Oxidation Test)
RULER (Remaining Useful Life Evaluation Routine)
MPC (Membrane Patch Calorimetry)
FTIR (Fourier Transform Infrared)
Colour (ASTM D1500)
Acid Number (ASTM D974)

One must be careful in selecting which test to apply, this is heavily dependent on the type of lubricant and its application.

For instance, if we perform the RULER test and the antioxidant levels have depleted significantly, we can suspect that oxidation is occurring or has stopped. Charting the rate of antioxidant depletion, can determine the rate of oxidation. This can assist us to forecast the time remaining before antioxidants have been depleted and can no longer protect the base oil.

Tagged: engineer

Properties of Additives in Lubricants

What is ICML 55?

What the difference between Shelf Life and Service Life?

Shelf Life

Service Life

What conditions affect lubricants?

Different types of lubricant degradation

What is Oxidation?

Oxidation Stages

Results of Oxidation

Oxidation Tests