Machinery, wear

Agricultural machinery Wear resistance Alumina, zirconio... 

Increase in equipment life-cycles by reducing machinery wear (frictions reduction) ... 

They require more power to cut, and knives and machinery wear more. 

Soot contamination is a common occurrence for in-service diesel engine oils. Soot generally results from piston ring blow-by from the combustion chamber or faulty seals. Soot contamination leads to varnish and sludge and also contains hard carbon particles that increase machinery wear. Detergent and dispersant additives function to clean machinery surfaces and hold soot particles in suspension, maximizing lubricant efficiency. 

In many cases, the most frequent cause of equipment outage is the lubrication system. Because magnetic bearings do not wear out, and do eliminate oil, pumps, filters, coolers, and regulating and mixing valves, the potential for improved reliability is obvious. Reliability is also enhanced by the control system, which offers continuous real-time protection. The system automatically shuts down before machinery damage can occur. 

All machinery with moving parts generates mechanical forces during normal operation. As the mechanical condition of the machine changes due to wear, changes in... 

Lubricating oil analysis, as the name implies, is an analysis technique that determines the condition of lubricating oils used in mechanical and electrical equipment. It is not a tool for determining the operating condition of machinery. Some forms of lubricating oil analysis will provide an accurate quantitative breakdown of individual chemical elements, both oil additive and contaminates, contained in the oil. A comparison of the amount of trace metals in successive oil samples can indicate wear patterns of oil wetted parts in plant equipment and will provide an indication of impending machine failure. 

Particle count tests are important to anticipating potential system or machine problems. This is especially true in hydraulic systems. The particle count analysis made a part of a normal lube oil analysis is quite different from wear particle analysis. In this test, high particle counts indicate that machinery may be wearing abnormally or that failures may occur because of temporarily or permanently blocked orifices. No attempt is made to determine the wear patterns, size and other factors that would identify the failure mode within the machine. 

Accuracy and reproducibility are of vital importance to industry. Quite apart from the effect of these factors on the final product, several plant items are frequently links in a continuous chain of production processes. A sizing error in one machine, for example, could overstress and damage the succeeding machinery. Similarly, an error in a press may increase stress on the tool and could necessitate an additional operation to remove excessive flash . Wear in a material preparation unit could allow oversize material to be passed to a molding machine, creating an overload situation with consequent damage. 

Indications of misalignment in rotating machinery are shaft wobbling, excessive vibration (in both radial and axial directions), excessive bearing temperature (even if adequate lubrication is present), noise, bearing wear pattern, and coupling wear. 

Other typical examples of defect limits are clearance tolerances of turbo-machinery assemblies, which are measured and recorded during machinery overhauls. Defect limits are not always as obvious as those stated above. Mechanical shaft couplings are very difficult to determine when serviceability is questionable, as they have no wear indicators to provide guidance. 

The second limitation is the life dispersion of machinery components. It is difficult to predict time-dependent failure modes because even they do not occur at the exact same operating intervals. Consider the life dispersion of mechanical gear couplings on process compressors. Both components are clearly subject to wear. If we conclude that their MTBF (mean-time between failure), or mean-time-between-reaching-of-detect-limit is 7.5 years, it is possible to have an early failure after 3 years and another... 

Never reach over operating machinery or wear loose clothing when working at or on machinery. 

The main function of most lubricants is to reduce friction and wear between moving surfaces and to abstract heat. They also have to remove debris from the contact area, e.g. combustion products in an engine cylinder, swarf in metal-cutting operations. Sometimes they have to protect the lubricated or adjacent parts against corrosion, but this is not a prime function of most lubricants. On the other hand, many lubricants do contain corrosion inhibitors and some lubricating oils, greases, mineral fluids and compounds are specially formulated to prevent the corrosion of machinery or machine parts, particularly when these components are in storage or transit. These temporary protectives are described in Section 17.3. 

Wear parts Bearings Jet-nozzle coatings Slurry valves Extrusion dies Abrasive pump seals Computer disk coatings Engine parts Medical implants Ball bearings Drawing dies Textile machinery... 

Displacement sensors are used in a very wide field of applications in research, development, quality inspection, automation, machinery and process control. Many physical parameters can be reduced to a displacement or change of distance, and can be measured with highest precision. Displacement sensors detect physical parameters like bending, deflection, deformation, diameter, eccentricity, elongation, gap, length, play, position, revolution, roundness, shift, stroke, thickness, tilt, tolerances, vibration, wear and width. 

In machinery, debris of any sort can lead to accelerated wear or direct breakdown. 

UHMWPE—battery separators, light-weight fibers, permanent solid lubricant materials in railcar manufacture, automobile parts, and truck liners liners to hoppers, bins, and chutes farm machinery as sprockets, idlers, wear plates, and wear shoes sewage-treatment bearings, sprockets, wear shoes lumbering-chute, sluice, and chain-drag liners neutron shield... 

Oils used to lubricate machinery, motors, hydraulic systems and other mechanical devices can sometimes contaminate fuel systems. These oils often carry with them low levels of the metals which wear from the lubricated surfaces of the mechanical components. Some common wear metals and possible sources of origin are listed in TABLE 4-12. 

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