Field Reporter Darieth visited the Hydrotex headquarters in Dallas, Texas for this episode of Tomorrow’s World Today. Through the visit, we learned about both the company’s history and some of the latest innovations happening in the world of machine lubricants. After learning about some of the most innovative new formulas out there, it’s also worth taking a look at some of the basics when it comes to lubrication. What are all of the benefits of lubrication and what are the basic building blocks behind creating a high-performance formula like those developed by Hydrotex?
Why Does Machine Lubrication Matter?
Your instinctual answer to this question may be that it helps the machine mechanisms become more pliable and therefore run more smoothly, but lubrication actually helps in several facets. Lubrication focuses on the friction produced when two mechanisms are rubbing together. As with any friction, heat will naturally be produced especially since mechanisms will likely be moving alongside each other very quickly. The heat produced could end up seizing or wiping your bearings, which would end up being extremely costly. Instead, operators will select a lubricant that meets their standard operating temperatures and speed.
But that’s not all lubricants help to prevent. Aside from producing heat, two machines rubbing together can cause microscopic pieces to break off into small abrasive particles which will go on to create more abrasion. There are a few different lubrication options that help protect against this: hydrodynamic films and elastohydrodynamic films. Layers of hydrodynamic films will create friction within themselves and form an oil wedge between the shaft and bearing, thereby protecting both from abrasion. Elastohydrodynamic films involve a softer material making up the rolling element, which will deform for a moment to enlarge the contact area between surfaces.
Although many factories employ seals and filters to avoid foreign particles in the system, it’s impossible to avoid them altogether and they can also cause machine damage. Choosing the proper lubricant can help keep this problem under control. Certain additives in lubricants can attract these contaminants and suspend them in the lubricant where they can be transferred out of the system through filters.
Another major problem machines naturally face is corrosion, which can be caused by humidity. There are additives specifically for machine lubrication that can help prevent this by repelling water from the metal surfaces. This will then help to prevent the production of rust, allowing a machine to operate smoothly for longer without the need for costly repairs or replacements.
Base Oil
The building blocks of a lubricant all start with base oil. There are three different types of base oils used in lubricants: mineral, vegetable, and synthetic. For industrial applications, however, the focus is primarily on mineral and synthetic oils. Mineral oils are mainly made from four molecules: paraffin, branched paraffin, aromatic, and naphthene. Paraffinic oils have a long straight-chained structure while branched paraffinic oils are the same way, but with a chain off to the side. These oils are mainly used for engine oil, processing oil, and industrial lubricants. Naphthene oils have a saturated ring structure while aromatic oils have an unsaturated ring structure.
There are also synthetic oils, which have identical straight-chained structures. With synthetic oils, the molecular size and shape are always constant while mineral oils vary greatly. While synthetic oils are much more reliable and predictable, synthetic oil can also be more costly, toxic, soluble, and can have hazardous disposal. In instances where a high flash point, fire resistance, low pour point, thermal stability, or high viscosity index is required, synthetic oils are the way to go.
Additives
There are different additives that can be added to a lubricant that will improve different functions of the machine wear. For example, dispersants will help protect against abrasion by enveloping particles and suspending them within the oil so that they can more easily be flushed out of the system. On the other hand, antiwear and extreme pressure additives will form a thin protective layer to prevent the metal to metal contact between the two mechanisms.
Detergents will work to neutralize acids and clean certain surfaces where the deposits may be detrimental. Defoamant additives, however, will work to weaken the surface tension of bubbles, allowing them to disperse more easily and minimize foaming.