In today’s competitive industrial world, you cannot afford to have machines that are not working 100% efficiently at all times. Even though lubrication may not get as much attention as new technologies or automation, it is key to running your operation smoothly. When everything is going well, it is easy to forget about it, but it is important to focus on lubrication to avoid problems and expensive breakdowns.

Oil Bleeding Out of Grease. If you see oil leaking out of a grease, either during storage or in  service, it is called bleeding. Heat, vibration, or simple gravity can cause the oil to separate from the thickener structure.

Solution: Switch to a grease with a more stable thickener. For instance, upgrading from a basic lithium grease to a lithium complex grease will usually improve mechanical stability and reduce bleeding.

Grease Caking. Grease that dries out or forms a hard cake is often suffering from excessive oil separation, evaporation, or compatibility problems between thickeners. Caking can also be the result of increased temperatures caused by over-greasing sealed housings.

Solution: Try a grease that can handle higher temperatures but be aware of grease compatibility problems. You may also need to adjust your service intervals – shortened greasing cycles for open bearings or increased intervals for enclosed bearings.

Mixing Incompatible Greases. When two incompatible greases are mixed, several performance capabilities can be negatively affected. The grease may undergo a change in consistency, either softening or stiffening. The mixture might also show a lowered dropping point, a change in its shear stability or an increase in oil separation. The biggest culprit behind incompatibility is thickener chemistry, but base oil and additive incompatibility can also play a role. Even products using the same thickener family (like changing from one lithium complex to another lithium complex) can behave differently depending on the formulation.

Solution: If you are unsure whether two greases are compatible, it is safest to assume they are not. Always purge old grease as much as possible and monitor equipment temperatures closely after any changeover.

Grease Will Not Flow Through a Centralized System. Grease that is too cold, too thick, or too tacky may clog lines and not reach critical components. Ideally, centralized systems need a softer grease (NLGI 0 or NLGI 1) with minimal tackifiers.

Solution: Inspect storage containers for oil pooling that indicates separation. If needed, move to a lower NLGI grade grease or one with a lower base oil viscosity. Always match the product to the design specifications of the system.

Other Dispensing Problems. Cold or improperly stored grease can cause air pockets in tubes and poor flow from containers. The absence of follower plates in grease drums can lead to dispensing problems as well as wasted product.

Solution: If you are using pail or drum pumps, ensure they have proper follower plates. A follower plate is a device making it possible to pump grease directly from a drum. The grease pump creates a vacuum that pulls the follower plate to the bottom of the container, as shown on the right, collecting the grease along the way down. A follower plate has four key benefits:

• Keeps the grease clean and preserves its characteristics.
• Compresses the grease and prevent air pocket formation and pump cavitation.
• Helps collect grease from the bottom of the drum, which would otherwise remain wasted.
• Improves the overall performance of the pump.

Grease Fails or Runs Out Prematurely

When grease breaks down too fast, the root causes often include heat, bearing speed, mechanical impact, or chemical contamination.

Solution: Lower the operating temperature if possible, improve contamination control, and select greases with higher viscosity base oils, more tackifiers, or a higher NLGI grade for better mechanical stability.

In the next issue of OilChat we will address some further common grease problems and how you can fix or prevent them. If you have any questions concerning grease in the interim, you are welcome to phone us on 011 462 1829,  email us at info@bcl.co.za. or visit www.bcl.q8oils.co.za.

In this three-part series of articles, we will focus on some of the most common problems you may experience with grease lubrication and endeavour to give you easy ways to prevent or fix them.

Identifying lubrication problems can be problematic when dealing with oils – and it gets even more difficult with greases. While oil analysis is fairly standard in most applications, in-service grease analysis is not done all that often and is harder to interpret. Grease specifications normally report the same basic properties, such as NLGI grade and dropping point, but critical details like base oil type, thickener chemistry and additive content may not even show up on technical data sheets. Physical characteristics like tackiness, water washout resistance and rheological behaviour are equally important, but are often undocumented.

Grease analysis is even harder once the grease is in service. Analysis options do exist – like ASTM D7918 (Standard Test Method for Measurement of Flow Properties and Evaluation of Wear, Contaminants and Oxidative Properties of Lubricating Grease by Die Extrusion Method and Preparation) or specialized wear debris testing. They are, however, not commonly used. Since grease operates mostly out of sight (inside bearings and housings, etc.) it is easy for problems to develop unnoticed until there is a major failure. Proactive grease sampling and monitoring should be part of a good preventive maintenance program, but it is still the exception rather than the rule.

Changing from one grease to another should be considered with due diligence. Before you switch products, it is critical to understand what is happening in the system. A few examples where trouble may arise include:

• Mixing greases unintentionally because someone used the wrong grease gun.
• Equipment speed increasing due to operational changes without evaluating if the grease can keep up.
• Rising operating temperatures stressing the grease beyond its rated limits.
• Storage conditions changing — hotter warehousing or outdoor locations causing grease degradation.

Another widespread “glitch” with grease is oil separation. When you open a container, chances are you may see a thin layer of oil at the top of the grease. The first thought that usually jumps to mind is whether the grease is suitable for use. Fortunately the answer in most instances is yes. A little oil pooling in a grease drum or pail is normal — especially after transportation or heat cycling.

If oil separation is minimal (up to about 6 mm), simply stir the oil back in. Excessive oil separation, however, can signal trouble. If the grease looks heavily separated or runny, contact your supplier.

Most grease performance problems do not boil down to grease chemistry alone — handling, application methods and operating conditions may play a huge role too. In the next issue of OilChat we will address more common grease problems and how you can fix, or even better, prevent them.

If you have any questions concerning grease in the interim, you are welcome to phone 011 462 1829, email us at info@bcl.co.za or visit www.bcl.q8oils.co.za.

A question often asked is what happens to all the empty spaces when billions of litres of crude oil is pumped out of the earth? To answer the question we need to understand how crude oil was formed.

Crude oil is also known as petroleum. The word petroleum literally means “rock oil” and is derived from the Latin words Petra (rock) and Oleum (oil). Wherever crude oil is found today the earth was covered with water millions of years ago. Crude oil and petroleum are called fossil fuels because they are mixtures of hydrocarbons that formed from the remains of animals and plants that lived millions of years ago in oceans, lakes, and swamps.

It all started 300 to 400 million years ago. Aquatic plants and animals (organic matter) died and  dropped to the bottom and were covered by sand and sediment – Fig 1. With time more and more layers of sediment deposited on top of the plant and animal remains and formed porous rock – Fig 2. Over millions of years heat from inside the earth and pressure from the layers of sedimentary rock above turned the organic matter into crude oil and natural gas – Fig 3.

Today we drill down through the layers of sand and sedimentary rock to reach the porous rock formations that contain the oil and gas deposits. Contrary to what you may have believed up to now, extracting the crude oil is more like sucking liquid from a sponge with a straw than from a puddle of liquid.

Now back to the initial question. You may assume that gravel or tumbling rocks fill the void, but the truth is much simpler. The pressure underground is extremely high and as the oil and gas are removed, other matter will be forced in to replace it. Consequently underground water from the adjacent area moves in to take up the space that has been vacated.

If you have any questions about petroleum topics or the complete range of Q8 lubricants, simply phone 011 462 1829, email us at info@bcl.co.za or visit www.bcl.q8oils.co.za.

The terms wire rope and steel cable are often used interchangeably, but there is a difference between the two. Wire ropes generally have diameters larger than 3/8 inch (10 mm). Sizes smaller than this are designated as cables. The major difference between the two, however, is in their construction.

Wire ropes are made up of multiple strands of wires twisted together. Each strand consists of several wires, and the strands are then twisted around a core (which can also be made of wires or other materials) as shown on the right. The construction allows for flexibility and strength, making wire ropes suitable for heavy lifting and rigging applications such as cranes, elevators, mine hoists and marine applications.

Cables are much simpler in design and normally consist of a single strand of wire or a few wires twisted together. They do not have the same multi-strand construction as wire ropes. A typical example is the brake cable on a bicycle.

Wire ropes wear from the outside, as well as from the inside. The outside wears as the wire rope moves over sheaves and pulleys and around winches or retaining drums. Along with dirt contamination, the rope is subjected to abrasive wear. The inside wears due to the inner strands rubbing and scuffing against each other as the rope is flexed and bent.

The extent to which wires move in a rope when it bends, is illustrated by the example of what actually happens when you wrap a 1 inch (25 mm) rope over a 30 inch (760 mm) sheave. The circumference of a 32 inch circle is slightly more than 6 1/4 inch longer than that of a 30 inch circle. Since the rope only touches half of the sheave at any time, the length differential which the rope must accommodate is 3 1/8 inch – almost 80 mm. This change of dimension is achieved by the sliding and adjusting of the strands in relation to one another, and a similar sliding and adjusting of the individual wires within each strand.

In addition to external and internal mechanical wear the rope also wears due to rust and corrosion.

Traditionally bitumen-based lubricants were used to protect wire ropes. These products must be heated before they can be applied since they are hard and thick at ambient temperatures. Some formulations contain a diluent or solvent to allow easier application. In low temperature conditions bitumen-based lubricants become very hard and brittle and fling off the rope. Environmental impact is another critical aspect of rope lubrication. Bitumen-based lubricants, when exposed to fire, release toxic fumes which pose significant health risks.

Nowadays more and more grease type wire rope lubricants are being used. Greases used for this application generally have a soft to semifluid consistency within NLGI grades 00 to 1. Wire rope greases typically offer the following benefits:

• Good covering properties
• They are water-repellent, water-resistant, and not emulsifiable
• Are not subjected to significant embrittlement
• Do not contain grit, abrasives, water, chlorine and impurities
• They are free from additives or compounds which can form corrosive products caused by water contamination or additive degradation.

Last, but not least, grease-based wire rope lubricants penetrate readily into the core of the wire rope when applied with a high-pressure lubricator.

If you require more information about wire rope lubrication, simply phone 011 462 1829 or email us at info@bcl.co.za. Our lubrication experts are at your disposal and ready to provide you with advice and answer any questions you may have.

The Stop/Start system is a technology found in many modern vehicles. Car manufacturers are being pushed to meet ever increasing emission standards and Stop/Start technology helps them to achieve the targets. A large number of vehicle owners, however, are concerned that this feature may be harmful to their engine and they simply switch the system off. The frequent stopping and starting of the engine is the reason for this concern.

Most of us are aware that the Stop/Start system automatically turns the engine off when the car is idling (at traffic lights, in traffic jams, etc.) to reduce fuel consumption and emissions. The engine restarts almost instantly when you lift your foot off the brake or press the accelerator.  Unfortunately the technology has downsides too. For some of these the motor oil has to compensate. The drawbacks include increased wear, high static friction and elevated engine temperatures.

The automatic Stop/Start systems in vehicles place much greater demands on the engine oil. The constantly interrupted lubrication and cooling of engine components during shutdown requires superior quality oils that meet certain high performance standards. We will delve into the specific requirements, why they arise and whether special lubricants are indeed required.

Increased Wear

A thin hydrodynamic lubricating film (see OilChat 22) separates moving surfaces during normal engine operation. Each time the engine is stopped, this oil film breaks down and the surfaces come into contact with each other. When the engine is restarted, the components operate in the boundary lubrication regime with increased friction and wear, especially when a substandard oil is used.

Furthermore, high static frictional forces are present in the stationary engine.  To overcome the static friction between mating surfaces, high forces are required to get the engine going again. This has a negative influence on the service life of timing chains, starter motors and batteries.

To compensate for these technical hitches motor oil for Stop/Start vehicle operation must provide maximum wear protection and should maintain an extremely tough and durable lubricating film. In addition, the oil needs to contain active chemicals that offer effective wear protection in boundary lubrication conditions.

Increased Temper­ature

When the Start/Stop electronics cut the engine out, flow of oil also stops. This can have fatal consequences on components subject to high thermal loads, such as the turbocharger. Since it is no longer cooled by circulating oil, the temperature inside the turbocharger increases dramatically. Heat from the extremely hot turbine wheel flows to the shaft and bearings and these components can heat up to temperatures exceeding 300°C. This can lead to oxidation and carbonisation of the oil and increased deposits.

So, do Start/Stop systems require special oils due to the increased engine loads? The answer is a surprising NO.

There is no need for such oils because there are no specific Stop/Start engine oil specifications that determine the suitability of a lubricant. Instead the overall performance credentials of the oil determine relevancy. For example an engine oil that conforms to the industry specifications ACEA A3/B4 and API SN/CF will perform satisfactorily in vehicles with Stop/Start technology. In addition, individual vehicle manufacturers may have their own engine oil specifications (e.g. Mercedes-Benz 229.3, Volkswagen 505.01, etc.) that take into account the requirements of their Stop/Start engines.

Q8 oil formulations meet and exceed the requirements of modern engine oil specifications. Our oils offer the highest possible lubricating film stability and their special wear protection chemistry ensures reduced wear and increased engine life, even under the most adverse conditions. Simply put, Q8 engine oils are so advanced that you do not need any special lubricants for engines with automatic Stop/Star systems. In fact, the high performance lubricants in the Q8 Formula engine oil range have been suitable for the severe requirements of vehicles with Start/Stop systems even before the technology existed.

For more information about the range of Q8 engine oils suitable for Stop/Start operation, phone 011 462 1829, email us at info@bcl.co.za or visit www.bcl.q8oils.co.za.