Selecting the appropriate grease for the job is a case of narrowing down your choices, this can be done by choosing a grease which is going to perform best for your specific application. There are a lot of different applications and a lot of different greases to choose from but the two most popular greases on the market today are Lithium Complex EP2 and Calcium Sulfonate.

Compassbearing

Note: This chart is a general guide to grease compatibility. Specific properties of greases can dictate suitability for use. Testing should be conducted to determine if greases are compatible.

When two greases are determined to have compatibility in the above three areas, more testing is carried out to determine the impact on other performance parameters of the products. Any test that is designed for measuring grease performance may be used on a mixture of greases to determine the effect on that parameter when the greases are mixed.

To "keep to a bearing" is not, in general, the same as going in a fixed direction along a great circle. Conversely, one can keep to a great circle and the bearing may change. Thus the bearing of a straight path crossing the North Pole changes abruptly at the Pole from North to South. When travelling East or West, it is only on the Equator that one can keep East or West and be going straight (without the need to adjust). Anywhere else, maintaining latitude requires a change in direction, requires adjustment. This change in direction becomes increasingly negligible as one moves to a lower latitude.

Bearingdefinition engineering

For calcium sulfonate grease, it is not uncommon for their scores to change by less than 20 units. That 280 Grade 2 grease may only change to a score of 295 or 300 instead of 310. Calcium sulfonate greases exhibit greater shear stability than lithium complex greases. And that means they will hold up under pressure, for longer, than lithium greases.

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So, the ASTM D217 test is used to document how the grease’s thickness may change over time. A sample of the grease is put in a machine and worked for 60 strokes, then 10,000 strokes, then 100,000 strokes. They then test the thickness of the grease at each point to see how it has changed. If the change in number is smaller than the more shear stability the grease has. A more stable grease thins out less over time exposed to long-term stress, and that's what we should be aiming for.

A bearing can be taken to a fixed or moving object in order to target it with gunfire or missiles. This is mainly used by ground troops when planning on using an air-strike on the target.

Bearingdefine

The measurement of absolute bearings of fixed landmarks and other navigation aids is useful for the navigator because this information can be used on the nautical chart together with simple geometrical techniques to aid in determining the position of the vessel.

Using compatible EP Greases and lubricants allows for a smoother operation of equipment, sometimes however certain environments command different types of grease or lubricants.

Get my bearings definition

At LRT Lubricants we have a wide range of greases available and the knowledge to help you find the right grease for your application.

Oil mostly relies on which additives and the nature of the base fluids to match the compatibility. When is comes to the grease compatibility it is often related to the thickness of the products being mixed but the base fluid compatibility is also just as important.

Let’s look at High Temperature Characteristics first. You will notice these are determined via the dropping point, the definition of dropping point is the temperature at which the grease passes from a semi-solid state to a liquid state which is the temperate reached that causes the grease to become fluid enough to drip. This then determines the upper temperature at which the grease retains its semi-solid state. Do not confuse this with the maximum temperature the grease can be used at which is lower. The upper operating limit for a grease is usually recommended to be 100-150F (40.56°C) lower than the dropping point.

To make matters more confusing, there are some grease specifications that are based only on grease performance without regard to grease configuration.

The compatibility of polyurea greases with soap-thickened greases is probably the most debated area of grease compatibility today. Grease based on simple lithium soaps (lithium stearate or lithium 12-hydroxystearate) and lithium complex soaps (containing simple soap and a complexing agent, such as lithium azelate) may not be compatible with polyurea greases.

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If the north used as reference is the true geographical north then the bearing is a true bearing whereas if the reference used is magnetic north then the bearing is a magnetic bearing. An absolute bearing is measured with a bearing compass.

Maze meaning

Clay based grease was not particularly good when mixed with Lithium and Calcium soap-based greases. The issue of grease compatibility has now become more complex than ever with the introduction of complex soaps,polyurea, calcium sulfonate and even more exotic thickeners used in many greases.

Grease compatibility and lubrication in commercial, industrial and automotive sectors is now more important than ever and most maintenance teams endeavour to create a consistent and reliable procedure. Using the same or similar products day in day out can help with this.

If greases of different thickener types (both of which meet the performance requirements of the specification) get mixed in a service, significant consequences could result.

Making the right decision isn’t easy but you need to look at what you want the grease to do. Does the application require the grease to have high water resistance? Or does it have to cope with High temperatures? Or even food safe applications?

When looking at a technical data sheet of a grease, you might see a reference to Worked Penetration at intervals of 10,000 and 100,000 strokes. These tests are carried out to document Shear Stability. Shear stability is one of the essential characteristics of any grease. Grease has to maintain its consistency under high shear conditions over a long period of time to be most effective.

If necessary, compatibility testing on combinations of these greases can be done to determine whether the greases can be mixed in service or not. It is imperative of the user of the greases to verify compatibility when making a change of grease from one product to another. Most grease suppliers have data on certain grease combinations or are willing to perform the required testing for their customers.

Alternatively, the US Army defines the bearing from point A to point B as the smallest angle between the ray AB and either north or south, whichever is closest. The bearing is expressed in terms of 2 characters and 1 number: first, the character is either N or S; next is the angle numerical value; third, the character representing the perpendicular direction, either E or W. The bearing angle value will always be less than 90 degrees.[1] For example, if Point B is located exactly southeast of Point A, the bearing from Point A to Point B is "S 45° E".[3] For example, if the bearing between Point A and Point B is S 45° E, the azimuth between Point A and Point B is 135°.[1][3]

A compass bearing, as in vehicle or marine navigation, is measured in relation to the magnetic compass of the navigator's vehicle or vessel (if aboard ship). It should be very close to the magnetic bearing. The difference between a magnetic bearing and a compass bearing is the deviation caused to the compass by ferrous metals and local magnetic fields generated by any variety of vehicle or shipboard sources (steel vehicle bodies/frames or vessel hulls, ignition systems, etc.)[4]

The relative bearing is measured with a pelorus or other optical and electronic aids to navigation such as a periscope, sonar system, and radar systems. Since World War II, relative bearings of such diverse point sources have been and are calibrated carefully to one another. The United States Navy operates a special range off Puerto Rico and another on the west coast to perform such systems integration. Relative bearings then serve as the baseline data for converting relative directional data into true bearings (N-S-E-W, relative to the Earth's true geography). By contrast, Compass bearings have a varying error factor at differing locations about the globe, and are less reliable than the compensated or true bearings.

In applications where grease compatibility is the concern then removing all of the original grease is not as easy and sometimes impossible. The best advise from most suppliers is to purge as much grease through the system when changing to help displace the old grease.

Bearing

If anyone where to mix 2 or more incompatible greases then the consequences could be dire. The greases may react to one another and cause the base oils to separate or the thickener oils could also separate, if this happens the base oils can’t stay in the same place for long and can get messy causing oil to ooze or the lubricant to run out of the area it was applied. Once this starts to happen parts such as bearings and other mechanical moving parts will start to wear prematurely and cause big problems later down the line.

Engine and gearbox oil are in most cases easy to change, if this is not possible the compatibility of the fluids can be quite easily determined.

To help users understand the implications of mixing greases, ASTM International (formerly the American Society for Testing and Materials) Committee D02.G developed ASTM D6185 Standard Practice for Evaluating Compatibility of Binary Mixtures of Lubricating Greases in 1997. This document details the procedure for evaluating the basic compatibility of greases, which is determined by measuring the dropping point, the mechanical stability and the change in consistency of the mixture upon heating.

The measurement of relative bearings of other vessels and objects in movement is useful to the navigator in avoiding the danger of collision. For example:

A grid bearing (also known as grid azimuth) is measured in relation to the fixed horizontal reference plane of grid north, that is, using the direction northwards along the grid lines of the map projection as a reference point.

Most lithium complex greases will have a typical score on this test to be around 30. A Grade 2 grease, may have started with a thickness score of, 280 (putting it in the middle of the range for a Grade 2 grease). After 100,000 strokes, the score may have changed to 310 (an increase of 30), which is just barely at the beginning range for Grade 1. So the grease changed from a mid-Grade 2 to a thick Grade 1. That's acceptable, if not ideal.

The measurement of relative bearings of fixed landmarks and other navigational aids is useful for the navigator because this information can be used on the nautical chart together with simple geometrical techniques to aid in determining the vessel's position, speed, course, etc.

The tests that are conducted should be settled upon between the user and grease supplier to assure that the properties that are critical to the proper function of the product in service are covered. The full description of ASTM D6185 is available from ASTM International at www.astm.org

Moving from A to B along a great circle can be considered as always going in the same direction (the direction of B), such as when holding fixed a steering wheel or ship's wheel. However, following a great circle does not keep the same bearing, which applies when following a rhumb line. Accordingly, the direction at A of B, expressed as a bearing, is not in general the opposite of the direction at B of A (when traveling on the great circle formed by A and B); see inverse geodetic problem. For example, assume A and B in the northern hemisphere have the same latitude, and at A the direction to B is east-northeast. Then going from A to B, one arrives at B with the direction east-southeast, and conversely, the direction at B of A is west-northwest.

If you were to compare the two most popular greases (Lithium complex and Calcium sulfonate) the calcium grease will usually out perform the lithium complex in the drop point test due to the properties of their soap complex. Regular lithium grease tends to drop around 350F (176.67°C). Lithium Complex drops at 500F (260°C) and Calcium Sulfonate grease approaches 600F(315.56°C) the extra 100 degrees in temperature for the calcium grease means it has an extra 100 degree of operating temperature range which can be an advantage for the equipment and environment it is being used in.

Grease compatibility can be confusing to those who have to maintain equipment correctly even if most of the manufacturers can produce compatibility charts. Not all manufacturers agree with the thickener combinations, in the past when manufacturers used clay and soaps as the primary thickeners grease compatibility was more straightforward.

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In navigation, bearing or azimuth is the horizontal angle between the direction of an object and north or another object. The angle value can be specified in various angular units, such as degrees, mils, or grad. More specifically:

In nautical navigation the absolute bearing is the clockwise angle between north and an object observed from the vessel.

In nautical navigation the relative bearing of an object is the clockwise angle from the heading of the vessel to a straight line drawn from the observation station on the vessel to the object.

This is due of the wide variety of materials that can react to form a thickener that is called polyurea. Some polyurea thickeners are entirely compatible with lithium and lithium complex thickeners, while other polyurea thickeners are definitely not compatible with the lithium and lithium complex thickeners.