Moisture is generally referred to as a chemical contaminant when suspended in lubricating oils. Its destructive effects in bearing applications can reach or exceed that of particle contamination, depending on various conditions. Like particles, vigilant control must be exercised over entry of water to minimize its accumulation in the lubricants and its damage to bearing surfaces.
This paper will discuss the influence of moisture on the chemical stability of a lubricant's additives and base stock. The effects of moisture on machine surfaces, particularly as relates to wear and corrosion, will also be discussed. Finally, a three-step, proactive maintenance strategy will be proposed to minimize the effects of moisture on lubricant and bearing life.
http://dramarnathgiri.blogspot.in/2012/12/the-second-most-destructive-lubricant.html?q=LUBE+OIL
This paper will discuss the influence of moisture on the chemical stability of a lubricant's additives and base stock. The effects of moisture on machine surfaces, particularly as relates to wear and corrosion, will also be discussed. Finally, a three-step, proactive maintenance strategy will be proposed to minimize the effects of moisture on lubricant and bearing life.
http://dramarnathgiri.blogspot.in/2012/12/the-second-most-destructive-lubricant.html?q=LUBE+OIL
Fouling Factors Fouling is a function of the system and the equipment used.
Fouling FactorsFouling is a function of the system and the equipment used. Parameters which influence the fouling rate in a system include: the type of fluid, the type of heat exchanger, the temperatures, the velocities and the materials of construction. The actual fouling rate is different for each application. There are numerous resources for fouling factor values. The best source is from existing operating facilities. When production data is available, it can be used to calculate the actual fouling factors for the system. Together with the maintenance and cleaning history, this provides the best resource for selecting the fouling factors for a particular application.However, when production data is not available, one must rely on other sources. Over the years, typical fouling factors have been compiled for various systems and fluids. The tables below show some of these typical fouling factors:
| Process Fluids | Fouling Resistance |
(ft2-°F-hr/BTU) | |
| Oils | |
| Fuel Oil #2 | 0.002 |
| Fuel Oil #6 | 0.005 |
| Transformer Oil | 0.001 |
| Engine Lube Oil | 0.001 |
| Gases and Vapors | |
| Acid gas | 0.002 - 0.003 |
| Ammonia vapor | 0.001 |
| Chlorinated hydrocarbons vapors | 0.001 - 0.0015 |
| Chlorine Vapor | 0.002 |
| CO2 vapor | 0.001 |
| Compressed Air | 0.001 |
| Hydrogen | 0.0005 |
| Hydrogen (saturated with water) | 0.002 |
| Light Hydrocarbon vapors (clean) | 0.001 |
| Natural Gas | 0.001 - 0.002 |
| Natural Gas Flue Gas | 0.005 |
| Nitrogen | 0.0005 |
| Polymerizable vapors (with inhibitor) | 0.003 - 0.03 |
| Refrigerant Vapors (oil bearing) | 0.002 |
| Solvent Vapor | 0.001 |
| Stable Overhead Products | 0.001 |
| Steam (non-oil bearing) | 0.0005 |
| Steam (exhaust, oil bearing) | 0.0015 - 0.002 |
| Liquids | |
| Ammonia Liquid | 0.001 |
| Ammonia Liquid (oil bearing) | 0.003 |
| CO2 Liquid | 0.001 |
| Chlorinated hydrocarbons liquid | 0.001 - 0.002 |
| Chlorine Liquid | 0.002 |
| DEG & TEG Solutions | 0.002 |
| Ethylene Glycol Solutions | 0.002 |
| Gasoline | 0.002 |
| Heavy Fuel Oils | 0.005 - 0.007 |
| Heavy Gas Oil | 0.003 - 0.005 |
| Hydraulic Fluid | 0.001 |
| Kerosene | 0.002 - 0.003 |
| Light Gas Oil | 0.002 - 0.003 |
| Light hydrocarbon liquid (clean) | 0.001 |
| MEA & DEA Solutions | 0.002 |
| Naphtha and Light Distillates | 0.002 - 0.003 |
| Organic Heat Transfer Liquids | 0.002 |
| Refrigerant Liquids | 0.001 |
| Water | Fouling Resistance | Fouling Resistance | ||
(ft2-°F-hr/BTU) | (ft2-°F-hr/BTU) | |||
| water temperature | 125°F or less | over 125°F | ||
| water velocity | 3 ft/s or less | over 3 ft/s | 3 ft/s or less | over 3 ft/s |
| Boiler Blowdown Water | 0.002 | 0.002 | 0.002 | 0.002 |
| Brackish Water | 0.002 | 0.001 | 0.003 | 0.002 |
| Condensate | 0.0005 | 0.0005 | 0.0005 | 0.0005 |
| Cooling Tower Water (treated) | 0.001 | 0.001 | 0.002 | 0.002 |
| Cooling Tower Water (untreated) | 0.003 | 0.003 | 0.005 | 0.004 |
| City or Well Water | 0.001 | 0.001 | 0.002 | 0.002 |
| River Water (minimum) | 0.002 | 0.001 | 0.003 | 0.002 |
| River Water (average) | 0.003 | 0.002 | 0.004 | 0.003 |
| River Water (muddy or silty) | 0.003 | 0.002 | 0.004 | 0.003 |
| Sea Water | 0.0005 | 0.0005 | 0.001 | 0.001 |
| Treated Boiler Feed Water | 0.001 | 0.0005 | 0.001 | 0.001 |