Edwards Enables: Engineering
One of the worlds tallest man-made structures, the Troll A gas platform used vacuum to initially ‘stick’ it to the sea bed. Vacuum is used to move gas from reserves and sea water dearation is a crucial process for oil pumping.
Oils, Fluids, Greases and Waxes
The V-Lube range of oils offer good thermal stability and oxidation resistance and have been selected for use with the Stokes range of vacuum pumps.
Edwards offers a range of new oils, Ultragrade® 15, 19, 20 and 70, which result from a new process. Most manufacturers use a solvent refining process, whereas these oils are produced by a unique hydrotreating process. This process eliminates nitrogen, sulphur and oxygen and the aromatic hydrocarbons, leaving a clear base stock essentially free of impurities.
When combined with additives, the Ultragrade® oils give improved vacuum performance, thermal and oxidation stability and rust inhibition. The anti-oxidants included in the oils enable the pump to withstand high operating temperatures without oil degradation, so extending intervals between oil changes.
The properties of the oils allow them to be used in a wide range of applications. New Ultragrade® 70 oils are the best choice for large pumps used in heavy-duty, cycling applications. Contact Edwards or your local supplier for detailed recommendations.
Edwards now offers an extended range of Fomblin® and Krytox®, perfluoropolyether oils for use in rotary vacuum pumps. Fomblin® YVAC 06/6 and Krytox® 1506 are recommended for Edwards oil sealed rotary pumps and are practically a direct replacement for mineral oil in terms of viscosity and vapor pressure. Krytox® 1525 is suitable for use in rotary pumps requiring a viscosity equivalent to Fomblin® Y25 fluid. Fomblin® Y16/6 and Krytox® 1514 are recommended for use in perfluoropolyether adapted mechanical booster pumps.
Edwards, in conjunction with Ausimont UK, has developed Drynert fluid which contains anti-rust and anti-wear additives soluble in Fomblin®. These additives cover metallic surfaces with a protective, corrosion resistant film
These synthetic fluids are organo-silicon oxide polymers and have exceptional chemical stability both at high temperature and when in contact with most gases and vapors. They provide a range of general purpose fluids for ultimate vacuum from about 10-5 to 10-9 mbar, and are particularly useful in industrial processing applications due to their exceptional ruggedness. High throughputs of air, water vapor and corrosive gases can be pumped without fluid degradation. The fluids can withstand repeated admission of atmospheric air while at operating temperature and are widely used in valveless quick-cycle pumping processes. They have low toxicity and good resistance to gamma radiation.
Fluid breakdown products (due to bombardment and so on) tend to be electrically insulating and so we do not recommend these fluids for physical electronic applications such as mass spectrometers and surface analysis systems. The fluids are indifferent lubricants. Their decomposition is catalyzed by traces of alkali metals (for example, caesium) and their use should be avoided where possible.
This synthetic fluid is a polyphenyl ether developed from fluids originally produced as lubricants for space vehicles. It has exceptionally low vapor pressure, exceptional thermal stability and a tendency to wet surfaces less readily and "creep" to a lesser extent than is common with most fluids. The fluid is employed for the cleanest high vacuum and ultra high vacuum applications down to less than 10-9 mbar (for example, electron microscopes, mass spectrometers and surface physics studies) where its excellent high vacuum performance and low tendency to migrate into the pump system particularly recommend it. The fluid is chemically stable, non-corrosive, safe and non-toxic at normal operating temperatures. Fluid breakdown products (due to bombardment and so forth) tend to be electrically conducting. Lubricating qualities are good and the fluid finds application to lubricate mechanisms in vacuum systems.
Use high purity Santovac® P5 Ultra for the most exacting mass spectrometry applications. Contact Edwards for more details and for ordering information.
Edwards 45 is a hydrocarbon synthetic polymer whose molecular structure offers chemical inertness, high temperature stability and low vapor pressure (<10-7 mbar at 25ºC). It is commonly used in mass spectrometry applications because of its well defined peaks. Edwards 45 oil is non-toxic, non-corrosive and reclaimable.
Edwards TW has been developed for applications where rotary pump oils are likely to be exposed to reactive or corrosive gases. The oil is distilled hydrocarbon containing no additives, but unsaturates and aromatic links have been removed. The result is that the oil will last up to 20 times longer, depending on process, than refined mineral oils. Longer oil life significantly extends the intervals between oil changes.
This grease is an excellent lubricant for sliding elastomer seals, and exhibits the chemical inertness typical of the Fomblin® range.
It has a very low vapor pressure and is suitable for use in the presence of gaseous and liquid oxygen under severe conditions.
The general purpose AR555 grease offered by Edwards has the basic properties of Fomblin®, but the vapor pressure is not specifically controlled. The vapor pressure is <10-7 mbar at 20°C
A range of Apiezon® greases is offered for use on high vacuum systems and for many general applications in the laboratory. These high purity greases are non-toxic, easy to apply, easy to clean off and have long shelf lives.
Apiezon® wax W is a low vapor pressure wax for sealing joints in high vacuum systems. This wax softens at 80-90°C and has a vapor pressure at 80°C of 10-3 mbar and at 20°C of 10-8 mbar.
Apiezon® wax W40 is similar to type W, but has a lower softening point which makes it very suitable for flow sealing in or around vacuum joints. It is not recommended for use at temperatures above 30°C. It has a vapor pressure at 20°C of 10-7 mbar.
Apiezon® sealing compound Q remains firm for temperatures up to 30°C, but is sufficiently pliable to permit easy moulding into position. It is an excellent material for shielding or blanking off sections of apparatus. The compound is easily applied and can be readily removed. It has a vapor pressure at 20°C of 10-4 mbar.
A high vacuum grade grease, which is for use at system pressures lower than 10-6 mbar.
Krytox® fluorinated greases are a family of multipurpose lubricants intended for use in speciality applications at elevated temperatures or in aggressive environments.
Apiezon® AP201 is a hydrocarbon fluid prepared by molecular distillation and protected against oxidation by a thermally stable additive of matched vapor pressure. It has an auto ignition temperature of 305°C.
It exhibits a fair degree of resistance to chemical degradation (so that high throughputs of air and water vapor can be pumped without damage to the fluid) and it can withstand limited accidental admission of atmospheric air at operating temperature. The fluid has low viscosity which permits easy filling and draining. It does not attack synthetic rubbers used for seals and gaskets in vacuum systems. It is non-irritant, non-toxic and environmentally non-polluting.