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1. Is new Tellus fully compatible with the old product?

Yes completely - whenever a Shell product is reformulated, the first constraint placed upon our lubricants research team is that the new product must totally be compatible with the old.

2. It’s all I can do to keep this business going at a profit, and you want me to pay more when hydraulic fluids aren’t all that important to me. Why should I listen to you?

We recognise you are interested in how you can achieve cost savings, minimize the downtime of your equipment and secure increases in productivity. At Shell we’ve made hydraulic fluids our business, and we’ve committed many years and significant funds in research and development to perfect a range of hydraulic fluids that are designed to give you cost savings, minimize down time and increase your productivity. By choosing Tellus, you draw on our professionalism and long experience in hydraulic fluids to give the things that are the most important to you.

So, don’t discount the importance of hydraulic oil in helping you to achieve your ultimate business goals.

What you put into your machinery will reflect in the productivity you get out of it…

3. Are all hydraulic oils the same?

The short answer is no.

It is important that as a user of hydraulic oil you determine what you need and want from your hydraulic oil and this will determine what type of oil you require.

Performance of hydraulic oils is very dependent upon the quality of base oil to ensure good filtration, trouble free operation and a long service life. The mix of additives and base oil is also critical to achieve the right performance cost effectively. Indeed, the additive combination within Shell Tellus Oils differentiates them so effectively from the competition that it has been patented.

Shell Tellus oil formulations have been developed to achieve optimum performance in the areas of thermal and oxidative stability, anti-wear performance, filterability, water separation, air release and foaming characteristics.

4. Are hydraulic oils performance tested?

Each hydraulic pump manufacturer has its own oil acceptance test, which incorporate their pumps in a series of rig tests designed to accelerate potential failure modes.

Shell has a full range of these rigs so that it can conduct its own independent fluid development work, often in conjunction with the hydraulic pump supplier. Today approval requirements are so stringent that well over 50 separate rig and bench tests are required to evaluate the performance of candidate hydraulic oils during development.

5. I'm perfectly satisfied with current Tellus - why should I buy the new product?

Hydraulic systems are moving to a new generation of fluid requirements. Next Generation Tellus has been formulated in response to developments in fluid power technology, which places greater demands on hydraulic fluids. All of the benefits you are enjoying with current Tellus are built in to the new product - in addition the improved features will provide you with a hydraulic oil catering for the more extreme applications where before it may have been necessary to use a special grade.

You have all the confidence you had in the old product, plus you get a significant improvement in product performance, which longer term means longer fluid and equipment life.

Think of the potential costs to your business if you did have a pump or valve failure.Next generation Tellus goes the extra mile to protect your machinery and extend fluid life, meaning increased profitability for your business. You will not get this peace of mind from an inferior quality hydraulic oil product. A small amount of money per litre on oil pales into insignificance when compared to the costs associated with machinery failure and downtime.

1. What's so special about Tellus compared to competitor products?

Through a process of continual research and testing combined with our long association with major equipment manufacturers, Shell is well qualified to identify those features of a hydraulic oil which are critical in modern fluid power systems.

Exceeding the performance requirements of major specifications is not sufficient in our view to satisfy the demands placed on a fluid in many modern applications. For instance no specification calls for anti-wear testing in 'low-load' conditions yet it is known through our own test programme that oils formulated to meet the high load situation can in some cases be totally inadequate in conditions thought to present no challenge to the fluid.

Shell's pump testing programme far outweighs that required to satisfy specifications: there is no specification calling for good filterability in the presence of both water and calcium. Yet it is known that these common contaminants can and often do cause problems with hydraulic oils.

There is no specification calling for anti stick-slip in actuators yet many applications depend on smoothness, in all modes of operation, This quality is not to be confused with the anti stick-slip properties of a slide-way oil. (The technology used for slide-ways does not solve the 'steel-on-seal' stick-slip phenomenon in actuators).

To our knowledge, none of our competitors has claimed to address the problem.

Shell's approach to formulating hydraulic oil is highly innovative - the Tellus formulation is unique & patented- Shell does not rely on additive manufacturers to provide a ready-made formulation. 

2. I have had a visit from one of your competitors who claims to use Shell base oil and claims to effectively have the same product as you, but it is cheaper. Why should I buy Shell Tellus?

If I watched a television cooking show with a world renowned chef, wrote down the recipe and purchased the ingredients to make the dish I saw. I then had a go at making it, would you believe me if I said that purely by virtue of trying to make the

recipe that I was a world class chef?

I think not… While some competitors do use some Shell base oils, this alone is no guarantee of product quality, as the IP in blending is significant in order to achieve perfect on-spec formulations.

3. I used to use premium oil, then I switched to a much cheaper competitor oil without any problems. Why should I switch back?

A small amount of money per litre on oil pales into insignificance when compared to the costs associated with machinery failure and downtime.

Lubricant expenses will typically only be 3-5% of your overall maintenance budget, the balance will be made up of other expenses such as spare parts costs etc. If you are using inferior quality lubricants, you may find that the savings you make on your lubricants are lost in extra spending on replacement machine parts.

Also, it may be that your system is in a period of lower use. Think about your next ‘busy period’. As a result of switching to cheaper oil, you may experience such phenomena as reduced system pressure, increased pump wear, and/or higher electricity expenses.

Like an engine oil, better quality hydraulic oil will stay in grade and keep working for longer. So drain intervals can be increased and less oil has to be purchased, and this will save you money in the long run, even although the per litre cost may be a little more.

1. My equipment is old so why do I need a high-spec hydraulic oil?

Older equipment remains as prone to wear and corrosion as new equipment -it still needs strong performance from the hydraulic oil in key areas.

Strong filterability performance allows for the fitting of finer filters. These will improve cleanliness, reducing wear and leads to cost savings through increased component life expectancy.

Older machines need greater levels of reliability and life expectancy can be maximised through the use of quality hydraulic oil.

2. My machine operates under light loads; does this affect the hydraulic oil I choose?

Light wear is almost as difficult to protect against as heavy duty wear because anti-wear additives may not be activated at low loads. Shell Tellus oils offer all round exceptional anti-wear performance.

Certain protection requirements (filterability, demulsibility and corrosion) are independent of load conditions.

Low load situations do not demand lower performance from the oil.

1. My equipment manufacturer is recommending that I use another oil 

If your equipment is under warranty, you should stick with the OEM recommendation during the warranty period. However, always check if the OEM approves Shell Tellus, as Shell has approvals from most major hydraulics manufacturers.1 in every 10 litres of hydraulic oil sold world-wide is Shell Tellus, a claim that no other major oil company can make.

Outside of warranty, remember that the OEM lubricant recommendation is only the minimum required for satisfactory performance. The goal of an equipment manufacturer is to sell more equipment; our goal at Shell is to prolong equipment life.

2. You state that some oils suffer filterability problems when contaminated with water and calcium. Surely this is an unlikely combination. Where would calcium come from?

Our tests show that the filterability of some oils is affected simply by water contamination and it is generally accepted that most systems will contain small amounts of water. Condensation can occur in the reservoir due to atmospheric conditions, storage of drums outdoors can allow breathing in of rainwater, and leaky water coolers all contribute to the ingress of water in a hydraulic system.

As far as calcium is concerned, it is clear from laboratory tests that only a few ppm of calcium in the presence of water is required to give rise to filterability problems with some oils. Many industrial environments carry airborne calcium. Calcium is a commonly used additive in engine oils and cross contamination between engine lubricants and hydraulic oils is not uncommon. Hardness salts in town water contain calcium, therefore contamination of a system with water via a cooler provides another source of calcium.

The reality is that the combination of water and calcium in a system is in fact quite likely, so you need an oil that can deal with this.

1. What is anti-wear protection?

Many anti-wear additives used in other oils become active only under severe loading conditions, and are unable to offer the same level of anti-wear protection under low load conditions. Shell technologists have evaluated the anti-wear performance of oils under both low load and high load conditions, and incorporated additives, which provide maximum protection at both extremes.

2. What are the benefits of air-release and anti-foaming properties in a hydraulic oil?

To ensure the efficient transmission of power, a hydraulic oil must be able to resist being compressed. Pressure applied to new hydraulic oil will be transmitted efficiently and instantaneously, but any air entrained in the oil, for example by foaming, will affect its compressibility; reducing the transmission efficiency and possibly resulting in inadequate lubrication, cavitations, oil loss and even mechanical failure.

The oil must therefore have good air-release and anti-foam properties. Tellus products meet all industry standards for air release and anti-foaming, such as IP 313 and IP 146.

3. What are the benefits of thermal stability in a hydraulic oil?

Hydraulic oils must be thermally stable to avoid the formation of deposits and sludge when subjected to high operating temperatures. Thermal stability, such as that in Tellus products, promotes cleaner systems and longer oil life, and reduces corrosion in ferrous or yellow metal components, thus minimising downtime and maintenance costs.

4. What are the benefits of oxidative stability in a hydraulic oil?

Hydraulic oils must be stable in the presence of oxygen, otherwise you will find deposits forming in the oil that will affect the performance of your system’s pumps and valves. Oils with poor oxidative stability will start to negatively impact your machine’s performance very quickly if the system is in regular use.

5. What are the benefits of hydrolytic stability in a hydraulic oil?

Hydraulic oils must be stable in the presence of water in the system, otherwise your oil can break down, leading to the formation of acids which will corrode system components. If left unchecked, total system failure could result and replacement costs for corroded parts will likely be significant.

6. Is new Tellus compatible with silver plated pump components?

Shell recommends the Tellus S range of oils for pumps containing silver-plated components. Laboratory tests show that oils utilising zinc technology vary considerably in terms of their effects on silver. Early ZDDP technology was incompatible with silver but recent Tellus formulations are not aggressive to this material except in the very severe applications where temperatures could be high.

We note that several of our competitors using ZDDP technology actually claim compatibility with silver plating but we prefer to take the precaution of recommending a special grade known to be totally compatible under all conditions.