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.

Many technicians, unfortunately, have relied on preventive, time-based lubrication alone, that is, every certain number of months, the grease gun comes out, and the bearings are lubricated. After all, under-lubrication can be lethal, causing equipment failure, costly repairs and replacements, significant unplanned downtime, and lost profits. But by relying solely on time-based lubrication, or even a combination of planned maintenance and temperature readings to serve as a proxy for lubrication status, one runs the risk of something just as bad, if not worse: over-lubrication. In fact over-lubrication can cause premature bearing failure.

Keeping a handle on lubrication is easy, right? All one needs to do is make sure the right lubricant is used in the right amount and at the right time. Not so fast; if only it were that simple.

Adrian Messer has worked in the maintenance and reliability field for nearly 20 years. During that time, he has worked with manufacturing and distribution facilities across multiple industries helping to improve their plant’s asset reliability through improved condition monitoring. Adrian is Manager of US Operations at SDT Ultrasound Solutions. Previously he worked with Progressive Reliability to advise companies on reliability-focused contracting & hiring and to find M&R professionals for open jobs.

Ultrasonic equipment detects airborne and structure-borne ultrasounds normally inaudible to the human ear and electronically transposes them into audible signals that a technician can hear through headphones and view on a display panel as decibel (dB) levels. In some instruments, the received sound can also be viewed on a spectral analysis screen. With this information, a trained technician can interpret the bearing condition in order to determine what, if any, corrective action is needed.

bearing中文

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.

Compassbearing

Update PMs to include the use of ultrasound when lubricating bearings.Establish baselines and alarm levels for all bearings: low alarm for lubricate, high alarm for potential failure analysis.All ultrasound testing is performed while wearing headphones to hear bearing sound quality.All data is logged and downloaded to data management software for trending and report generation.Review all data using low and high alarm levels.

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.

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.

The first step is establishing both a baseline dB level and a sound sample. This is ideally done when moving through a route for the first time by first comparing dB levels and sound qualities of similar bearings. Anomalies will be easily identified. Once established, each bearing can be trended over time for any changes in either amplitude or sound quality.

Bearingdefine

It is always a daunting proposition to make a new investment in technology. Will it pay off? Will my staff actually have an easy time using it?

Most bearing failures are lubrication-related. Bearing failures most often lead to unplanned downtime, which can impact production, as well as affect all related components around the bearing. Downtime is costly. While the cost varies by incident and by plant, it can add up. Since the most common cause of bearing failure is lubrication-related, it’s clear to see that lubrication is serious business. And for the longest time, that serious business has been conducted in a way that on its face makes perfect sense but in fact borders on haphazardness.

Relying on time-based, periodic lubrication assumes bearings need to be greased at defined time periods. Often, this evolves into a well-intentioned guessing game at best. Adding more lubrication to a bearing that is already adequately greased is a real risk.

Bearing

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.

There are still many plants that are figuratively using crystal balls and outdated methodologies in their maintenance practices. The end result is poor reliability, unnecessary man-hours, downtime, and lost productivity and profit. While technology can’t cure all reliability ills, it can offer a valuable and powerful diagnostic tool for technicians’ toolkits. When it comes to something as important to reliability as lubrication, the question really becomes, “Can you afford not to use ultrasound technology?”

Bore meaning

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

Ultrasonic technology helps the lubrication technician take a lot of the guesswork out of lubrication needs. Ultrasound is a localized signal, meaning when a sensing probe is applied to a bearing it will not be affected by crosstalk and allows the technician to hear and monitor the condition of each individual bearing. Ultrasound looks at each individually, much the same way medical ultrasound can detect exactly which artery is clogged or which vein is leaking.

Havebearingon

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.

Types of bearings

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:

Generally speaking, when the amplitude of a bearing exceeds 8 dB and there’s no difference in the sound quality established at baseline, the bearing needs to be lubricated. To prevent potentially disastrous over-lubrication, the technician will then apply lubrication, a little at a time, until the dB level drops. Many departments set up their condition-based lubrication programs by incorporating a two- stage approach. The reliability inspector uses a relatively sophisticated ultrasound instrument to monitor and trend bearings. A report of bearings in need of lubrication is produced. The lube technician then uses a specialized ultrasound instrument that alerts the technician when to stop adding grease. These instruments can be affixed to a regular grease gun or worn in a holster (Figure 2).

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.

Adrian is a graduate of Clemson University with a Bachelor of Science in Management with a concentration in Human Resources. He is a Certified Maintenance and Reliability Professional (CMRP) through the Society for Maintenance and Reliability Professionals (SMRP) and is actively involved with SMRP on a local and National level. He resides in Anderson, South Carolina.

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.

To improve efficiencies, it’s a good practice for the technician to note when the equipment was last greased and how much grease was used to calculate roughly how much lubrication is used per week. By using ultrasound to lubricate each and every time, the technician produces historical data that can be used as a guide from previous calculations, helping the department to determine whether the lubrication schedule can be modified, perhaps saving man-hours, and whether the manufacturer’s suggested lubrication amount is accurate. If less is needed, there’s cost-savings potential.

bearing数学

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]

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:

And while most of this discussion has focused on the dangers of under- and over-lubrication, ultrasound is just as reliable in picking up other potential bearing failure conditions. The technician, using ultrasound, can hear telltale grinding sounds and other anomalies, which are often accompanied by an amplitude increase. With regard to lubrication, the advantage of ultrasound is that it is able to isolate bearings and determine their individual needs, thus reducing the possibility that some bearings are too dry and prevent others from over-lubrication.

Figure 1. By using ultrasound technology technicians can gain a clearer picture of what’s really going on and improve reliability. Relying on time-based, periodic lubrication assumes bearings need to be greased at defined time periods. Often, this evolves into a well-intentioned guessing game at best. Adding more lubrication to a bearing that is already adequately greased is a real risk.By using ultrasound technology, along with standard practices such as removing old grease and replacing it with new, technicians can combine standard, time-based maintenance with condition-based, predictive maintenance, gaining in the process both a clearer picture of what’s really going on and better reliability (Figure 1).Ultrasound and lubricationUltrasonic equipment detects airborne and structure-borne ultrasounds normally inaudible to the human ear and electronically transposes them into audible signals that a technician can hear through headphones and view on a display panel as decibel (dB) levels. In some instruments, the received sound can also be viewed on a spectral analysis screen. With this information, a trained technician can interpret the bearing condition in order to determine what, if any, corrective action is needed.Ultrasonic technology helps the lubrication technician take a lot of the guesswork out of lubrication needs. Ultrasound is a localized signal, meaning when a sensing probe is applied to a bearing it will not be affected by crosstalk and allows the technician to hear and monitor the condition of each individual bearing. Ultrasound looks at each individually, much the same way medical ultrasound can detect exactly which artery is clogged or which vein is leaking.As an example of ultrasound’s efficacy, consider this. A maintenance manager at a large firm reports that, since adopting ultrasound technology and practicing ultrasound-assisted, condition-based monitoring, rather than running to put out the fire, his plant has gone from close to 30 rotating equipment failures per year to zero in three years. But how does ultrasound work, exactly, vis-à-vis lubrication?The first step is establishing both a baseline dB level and a sound sample. This is ideally done when moving through a route for the first time by first comparing dB levels and sound qualities of similar bearings. Anomalies will be easily identified. Once established, each bearing can be trended over time for any changes in either amplitude or sound quality.Generally speaking, when the amplitude of a bearing exceeds 8 dB and there’s no difference in the sound quality established at baseline, the bearing needs to be lubricated. To prevent potentially disastrous over-lubrication, the technician will then apply lubrication, a little at a time, until the dB level drops. Many departments set up their condition-based lubrication programs by incorporating a two- stage approach. The reliability inspector uses a relatively sophisticated ultrasound instrument to monitor and trend bearings. A report of bearings in need of lubrication is produced. The lube technician then uses a specialized ultrasound instrument that alerts the technician when to stop adding grease. These instruments can be affixed to a regular grease gun or worn in a holster (Figure 2). {pb}

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.

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]

As an example of ultrasound’s efficacy, consider this. A maintenance manager at a large firm reports that, since adopting ultrasound technology and practicing ultrasound-assisted, condition-based monitoring, rather than running to put out the fire, his plant has gone from close to 30 rotating equipment failures per year to zero in three years. But how does ultrasound work, exactly, vis-à-vis lubrication?

By using ultrasound technology, along with standard practices such as removing old grease and replacing it with new, technicians can combine standard, time-based maintenance with condition-based, predictive maintenance, gaining in the process both a clearer picture of what’s really going on and better reliability (Figure 1).