All new systems will contain some contaminant left during manufacture and assembly. This usually consists of fibrous material from rags, casting sand, pipe-scale, cast iron and other metal particles, jointing material and loose paint.
When a normal system has been run-in for a reasonable period, the majority of solid contaminants will be in the form of small platelets, created by bedding-in and the normal wear process, the bulk of which are between 5 and 15 microns in size. Because of their size and shape, they can take a long time to settle.
The other common form of self-generated contaminant is that local cold welding microscopic surface particles will be torn off when they move in relation to each other releasing wear particles.
Unless extreme care is taken in filling and topping up a system, considerable quantities of contaminant can be added during these processes. Many of these contaminants are likely to be abrasive.
A lubricating system can also be contaminated by ingression through the oil film on seals. Worn seals will increase this possibility. Contamination will be introduced if all reservoir openings are not fitted with Industrial Filters.
The other mechanisms that cause self-generating contaminants include: adhesive, abrasive, erosion, fatigue, de-lamination, corrosive, electro-corrosive, fretting corrosion, cavitation, electrical discharge and polishing wear. Each of these types of wear categories has its own mechanism and symptoms, however in practice they may occur singularly, combined or in sequence.
A new lubricant fill in a machine is kept clean by the action of Industrial Filters and by the chemical action of the additive package in the lubricant. The types of filters used in most instances remove solid or gelatinous particles to the limits of the filter. These filters do not generally remove the liquid or gaseous contaminants.
Effective contamination control is not just a matter of filters. System planning, location of filters, heat exchanger capacity, etc. are but a few of the items that have been considered in a machine’s design to reduce the generation of particulate contamination.
Barring isolated instances, it is generally recognized that by having clean lubricant, equipment will give better performance and more reliability. Changing filter elements at given regular time interval, is not desirable, nor necessary.
If installed, filter elements should be changed whenever the differential pressure across the filter exceeds the suggested maximum differential. The degree of filtration (micron rating) will depend on the type of equipment and /or the manufacturers recommendations.
When a normal system has been run-in for a reasonable period, the majority of solid contaminants will be in the form of small platelets, created by bedding-in and the normal wear process, the bulk of which are between 5 and 15 microns in size. Because of their size and shape, they can take a long time to settle.
The other common form of self-generated contaminant is that local cold welding microscopic surface particles will be torn off when they move in relation to each other releasing wear particles.
Unless extreme care is taken in filling and topping up a system, considerable quantities of contaminant can be added during these processes. Many of these contaminants are likely to be abrasive.
A lubricating system can also be contaminated by ingression through the oil film on seals. Worn seals will increase this possibility. Contamination will be introduced if all reservoir openings are not fitted with Industrial Filters.
The other mechanisms that cause self-generating contaminants include: adhesive, abrasive, erosion, fatigue, de-lamination, corrosive, electro-corrosive, fretting corrosion, cavitation, electrical discharge and polishing wear. Each of these types of wear categories has its own mechanism and symptoms, however in practice they may occur singularly, combined or in sequence.
A new lubricant fill in a machine is kept clean by the action of Industrial Filters and by the chemical action of the additive package in the lubricant. The types of filters used in most instances remove solid or gelatinous particles to the limits of the filter. These filters do not generally remove the liquid or gaseous contaminants.
Effective contamination control is not just a matter of filters. System planning, location of filters, heat exchanger capacity, etc. are but a few of the items that have been considered in a machine’s design to reduce the generation of particulate contamination.
Barring isolated instances, it is generally recognized that by having clean lubricant, equipment will give better performance and more reliability. Changing filter elements at given regular time interval, is not desirable, nor necessary.
If installed, filter elements should be changed whenever the differential pressure across the filter exceeds the suggested maximum differential. The degree of filtration (micron rating) will depend on the type of equipment and /or the manufacturers recommendations.
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