Archive for July, 2014

How Temperature Affects Lubricants

Friday, July 25th, 2014

Considering temperature can dramatically affect lubricants, multigrade engine oils have a winter rating and an operating temperature rating. The oil chemistry is altered with even the slightest temperature change, though. Temperature indeed affects lubricants in many different ways.

I’ve talked about viscosity in one of the previous posts. Oil that has a lower viscosity on top of high potential shear rate should still maintain adequate oil film. However if the lubricants that were damaged by the temperature they will not deliver very well, causing metal-to-metal contact.

On the other hand, when the oil’s viscosity is too high, with a low potential shear rate, the internal resistance to flow will make the temperature shoot up drastically. Should that happen, an overheated condition will likely occur. This could also bring about a breakdown of the oil film and may yield oxidation of the oil.

The pour point of lubricant is described as the lowest temperature where the oil flows. Most of the time, it is erroneously used as the oil viscosity selection criteria.

Just so you know, the oil with a pour point of minus 30 degrees C and operating in an ambient temperature of minus 30 degrees C will churn at the oil pump up to the point where temperature increase affects churning of the lubricants. Consequently, it will allow the oil’s viscosity to thin amply in order for it to slowly start flowing through the oil passages to the lubricated components.

Lubricants are known to degrade when affected by extremely high temperatures. How? Oxidation happens, and it’s irreversible at that. The oxidation of the oil is not the only problem; the additives are also depleted at a higher rate as well. Temperature affects synthetic lubricants to a much lesser degree. No wonder why the synthetics are often better suited for extreme operating temperatures.

All About Sealable and Reusable Containers

Friday, July 18th, 2014

Sealable and reusable (abbreviated as S&R) containers are becoming commonplace in the lubrication industry. They are available in different styles and sizes to cater to your needs and specifications. They can have a direct impact on your lubrication program. They help keep particle ingression into new oils and cross-contamination of different oils at bay.

Moisture and particles can enter lubricants during handling and transportation. For small machines, between the bulk or intermediate storage and the machine itself, the lubricant could be badly contaminated. This is where S&R containers come in handy.

Proper care of an S&R container is vital. Such involves always keeping these containers tightly sealed when not in use. Also it’s important to label them to eliminate possibilities of cross-contamination of different oils when refilling the containers. Furthermore, they should be kept clean on the inside and out and must be stored in a nearby cabinet when not in use.

The use of quick-connects on the hand-pump models is yet another way of preventing contamination. With it, the container will be kept sealed from any outside contaminants lurking around in your environment.

If you take clean oil from bulk storage areas and put it into a sealable and reusable container that has been sitting around with the lid off, or when you use the same container for every oil, you’re just wasting time and energy. It’s a necessity for machines to have clean oil.

How to Clean

• Throw away any remaining lubricant into appropriate waste containers.

• Use a sponge to wipe the container clean using warm water and soap, and rinse properly.

• Wipe the container dry with the use of a lint-free rag/cloth.

Recently, automatic parts cleaning systems have been surfacing. Such systems pave the way for continuous workshop productivity. How exactly? Well, we could bid farewell to the process of cleaning containers by hand!

Rather than hand-cleaning every single container one at a time, an automatic parts cleaner allows for several containers to be cleaned all at the same time. Now isn’t that innovative?

Viscosity – the Most Important Characteristic of a Lubricant

Friday, July 11th, 2014

Viscosity is the measurement of fluid internal resistance to flow at a certain temperature. You can measure a fluid’s viscosity in two ways, namely Dynamic (Absolute) Viscosity and Kinematic Viscosity.

It’s no secret that viscosity is deemed the most essential parameter in oil lubrication systems. It’s always necessary that the oil’s viscosity meets the standards of OEM. Considering the main purpose of lubrication oils is producing and maintaining lubrication films between two moving metal surfaces, oil viscosity is important because such function depends on it.

A condition called insufficient lubrication usually comes about when the viscosity of the oil is outside the recommended viscosity range. That said, increased friction, wear, and heat follow suit.

Viscosity is among the required tests during routine in-service oil analysis. Any considerable change that will be observed in the measured viscosity will call for immediate action. It could be a red flag for severe degradation of oil, cross contamination, water ingression or other factors which can be confirmed when you look into other characteristic, such as water content.

Viscosity monitoring is important. Why? It’s because majority of component surfaces are separated by a lubrication film thickness of 10 micron or less. This applies most particularly for high pressure systems, like hydraulics or high speed turbochargers, as maintaining the correct oil viscosity becomes even more vital. Drastic changes in oil viscosity, whether it be a reduction or increase, could cause damage to lubrication film stability as well as its effectiveness.

Being the most significant parameter for lubricating oil, viscosity of in-service oil should be strictly monitored as a routine parameter during oil analysis. But in order to reap the most benefits when doing oil analysis, other significant characteristics should also be analyzed so as to get the holistic view of oil and the current state of machines.

Drain Intervals for Heavy-Duty Vehicles

Thursday, July 3rd, 2014

In the past, a truck engine oil drain/change would have been done as often as every 500 miles. Due to higher quality lubricants that we have nowadays, on top of cleaner fuels, enhanced filter technology and much more reliable engines, an oil drain interval as high as 50,000 miles or more on these same types of vehicles is now possible.

Even so, the usual oil drain intervals are still about 25,000 miles. Modifying this standard is a little too far down the road, considering all the challenges that this type of vehicle comes across. For instance, two identically manufactured vehicles could go through a totally varied oil life; one could come close to 50,000 miles, whereas the other could starve for fresh oil by 15,000 miles. This diversity in engine oil life is the outcome of a wide array of factors from three main areas:

  1. Engine Design, Age and Conditions – Engine design features and several running conditions could create an impact on oil life factors from exposures to contaminants along with many other conditions.
  2. Driving Patterns and Conditions – The places and the way the truck is driven.
  3. Oil Properties – Quality and formulation performance of the engine oil.

Engine fuel efficiency plays a significant role in the engine oil’s life. It is improved through combustion efficiency, from which you can determine the type and amount of particles blown by the piston rings.

For the most part, piston “blowby” is the main source for ingression of contaminants into the oil. Such could include dirt, water, soot, fuel, nitrogen oxide as well as partially burned hydrocarbons. Seal efficiency, temperature control and emissions control methods also have an impact on the type and concentration of contaminants in the oil.

Other engine characteristics like total operating hours and mileage are inevitable and could bring about lessened oil drain interval, but having and keeping a healthy oil-flow system is doable through consistent and sufficient filtration and seals.

Filtration can keep contamination at bay. That being said, the dirt-holding capacity of the filter being in-line with the needed oil drain interval is a necessity.

Another engine characteristic that can impact oil drain intervals is the oil capacity or sump size. On the whole, with more engine oil that circulates within the engine, the less the contamination concentration gets. Bigger sump size also indicates more oil additives and less thermal distress. That said, engine makers that have the biggest sump size normally allow for the industry’s longest recommended oil drain interval.