The Braycote line of greases cover a very wide range of applications and consequently, a large number of different products, often times varying only slightly, but having large differences in certain applications. The product range has been very confusing for many who have approached it for the first time, so let us try first to clarify some of the important points:
Micronic® Designation:
If a grease is designated as "Micronic", for example, there is Braycote 803 and there is also Braycote Micronic 803, this means that the grease has been extruded through a screen pack filter to remove any PTFE agglomerates larger than one 祄. Generally speaking, the Micronic form of the same product is more uniform and homogeneous and when applied to "O" rings, for example, in an electron microscope, the final remains of the lubricant are much less "gritty" than would be the case for Braycote 803. That is why for the electron microscope application, there is a preference for the Micronic form of the product.
Cost: Generally speaking, the Micronic form of the same product is more expensive by a noticeable amount.
Effect of Braycote greases on "O" rings:
Generally speaking, the more common materials used in the construction of "O" rings are pretty inert exposed to any of the Braycote greases. However, one does have to be careful when the "O" ring is a fluoropolymer itself, for example, PTFE, particularly when used at temperatures above 150癈. There will not be anything like a chemical reaction, but the "O" ring can start to act like a "sponge" for the base oil, leaving a pile up of the grease thickener on the outside of the "O" ring. The solution is to presoak the "O" ring in the base oil prior to installation. This will saturate the "O" ring and reduce greatly the rate at which additional liquid is soaked up by the "O" ring.
There has been compatibility testing done by some of the seal manufacturers using PFPE greases with silicone and fluorosilicone compounds. The materials were found to be compatible. However, as expected, there can be some minor changes to the seal/"O" ring properties, i.e. slight changes in hardness, tensile strength, elongation, and volume. It is always recommended that for critical applications, the customer do their own evaluation and testing of the intended Braycote product for compatibility in their specific application since the ultimate decision on appropriateness in a given application rests solely with the customer and not with SPI Supplies.
Environmentally Friendly, the "EF" designation:
Some Braycote grease products have an "EF" designation for example, Braycote 601EF or 602EF. This designates that it is a reformulated product from what was at one time products with designations of Braycote 601 and Braycote 602. The reformulation was done to take advantage of newer and more environmentally friendly manufacturing processes, but at the same time, the product itself, in some very subtle ways, is not quite the same as the product it was replacing. To our knowledge, anyone using, for example, the older and original Braycote 601, could probably make a plug-in compatible substitution with Braycote 601EF. But the user should be aware that there are some subtle differences and that you should do the needed testing to make sure that the "EF" form of the product will indeed work just as well in your products as the original product.
Rust Preventative, the "RP" designation:
For some applications, it is desirable to incorporate into the vacuum grease solution, a rust preventative and those greases that have an "RP" designation after the product number, are those that have had this additive incorporation into the formulation. Such an additive would not, in general, add value to a static "O" ring type application. But it could add value in a situation where moving parts were involved. One should not in general, use the RP version of a formulation unless it is truly needed because some of the other desirable characteristics, for example, ultimate vapor pressure and weight loss characteristics are reduced slightly. Not all products are available with the "RP" designation.
Compatibility Considerations:
The Braycote family of high vacuum greases has been formulated to be, in general, compatible with LOX\GOX (liquid oxygen/gaseous oxygen) and all forms of chlorine. So far as we know, no reaction will occur. However, this statement should not take the place of your own testing should there be even the slightest possibility that this statement might not apply in your own specific situation and system.
As a class, the Braycote high vacuum greases are compatible with most commonly utilized materials, plastics, and elastomers. However, the lubricants may be adversely affected by Lewis Acid catalysts such as aluminum chloride, at elevated temperatures. Newly exposed rubbing surfaces of aluminum, magnesium and titanium alloys may react with these products as well. It is always the responsibility of the user to thoroughly investigate any applications where these problems could occur.
Fungi growth resistance:
For long term use under conditions of high humidity, one must be concerned about fungi growth possibilities in the grease/lubricants being used. The greases are free of any hydrocarbons and the fully fluorinated structure, both liquid and solid phases just will not support fungi growth and therefore meet the test of being fungi resistant. For further information: Military application, Spec MIL-HDBK-454A, Table 4-I. Fungi susceptibility of materials.
If you do not see the Braycote product you are looking for, let us know, because this section is still being constructed and chances are we can get whatever Braycote grease you require.
Radiation resistance:
We are asked this question more and more frequently. We apologize for not having better information. However, we do know about one study performed some years ago in which a Z fluid, possibly Brayco 815Z, was exposed to gamma radiation from a Cobalt 60 source. After exposure at 50 mrads the oil showed a weight loss of 0.1% and a viscosity decrease of 30%. There was no apparent formation of sludge or polymeric material. This is the only data we know about that deals with radiation exposure.
Lithography applications:
As indicated above, there does not exist, to our knowledge, information about radiation resistance. But for those doing lithography, outgassing and the presence of silicones seem to be the greatest concerns. The outgassing properties of all of the Braycote products are excellent. And we are happy to report that none of the Braycote greases contain any silicones.
Shelf life considerations:
This is a commonly asked question and there is no easy answer. In general, these products are quite stable, and the manufacturer Castrol, will guarantee all of the Braycote products shown on this page, in unopened containers, for twenty years. The lubricants themselves are quite stable chemically, but physically, with the passing of time, there can occur a separation of the liquid phase with the PTFE solids phase.
The twenty years does not apply if the container has been opened or if an unopened container has not been stored according to instructions.
If you should have a critical application, and if you have a large supply left over from a previous order, then it can be recertified, for a nominal fee. Send us full information via our Ask a Question or Make a Comment form and we will respond with information about cost and turnaround times. Generally speaking, unless you have more than one pound of the lubricant for recertification, it is cheaper to just purchase new material. For some of the lower cost greases, that "cross over" point might be closer to 2 pounds. Just remember that for non-critical applications, even if you do see some oil separation, after some mixing, the grease can be brought back to essentially its original specifications. Now this is not the official recommendation of the manufacturer, it is just our own experience over the years when confronted with older material for which there has been oil separation.
Removal of unwanted grease from grease applied surfaces:
The composition of this product is a mixture of small PTFE particles (which won"t dissolve in anything) and a perfluorinated polyether liquid. We have found that Castrol® Fluoroclean™ HE is an effective solvent for the liquid component of the formulated composition and aids in the removal of the grease from places where it is no longer needed or wanted.
Physical stability, which is something often times overlooked by the most seasoned of engineers should also be taken into consideration. The Braycote greases are all two (or more) phase systems and eventually the different phases will separate out, resulting in heterogeneities in the grease. But keep in mind that this kind of separation, which is thermodynamically driven, is like death and taxes: You can"t do a thing about it. But fortunay, the separation rate is ver slow, and it can even be slowed down by storage of the grease product under refrigerated conditions.
pH values: The determination of pH is not normally a test that is run on any of the Braycote PFPE products. We can report, that on the base oil for Braycote 601EF, there is run a test to determine the Neutralization Number which is reported in mg KOH/g with typical values of 0.02. We are of the opinion that a neutralization test provides a better indication of levels of acid than pH. When pH values have been run, not on Braycote products but on other PFPE oils of similar chemistries to the Braycote 815z, the values typically have been in the 5-6 range.
Additional critical information about compatibilities and solubilities:
All Braycote greases are a two phase system consisting of PTFE particles dispersed in a "base liquid". The information below pertains to the base liquid and not to the PTFE particle portion of the formulation. - Gas solubility
- Solvent solubility
- Chemical resistance
- Plastics compatibility
- Elastomer compatibility
Listing of products: Vacuum Greases
Braycote 600EF Braycote 601EF Braycote 602EF Braycote 614EF Braycote 615
Braycote 631A Braycote 631RP Braycote 640AC Braycote 640ACMS
Braycote 802RP Braycote 803 Braycote 803EP Braycote 803RP Braycote 804
Braycote 806 Braycote 806RP Braycote 807 Braycote 807RP Braycote 1616
Braycote 1624 Braycote 1625 Braycote 1632 Braycote 1636
Braycote Braycote Micronic Braycote 600EF Braycote Braycote 601EF
Braycote 700 Braycote 701 Braycote 803 Braycote 1613 Braycote Brayco Micronic
Braycote Braycote 815z Braycote Microcote® Products Braycote 096, 196, 296
Braycote LVP Braycote Brayco Base Oils Braycote Braycote 812
Braycote 814 Braycote 815z Braycote 849 Braycote 1624 Braycote 1625
Braycote 1721 Braycote 1721 PLUS Braycote 1722 Braycote 1723
Braycote 1723 PLUS Braycote 1724 Braycote 1724 PLUS Braycote 1726 PLUS
Braycote 1727 PLUS Braycote 1728 Braycote 1729
Braycote Braycote Braycote Optitool 215-2
Braycote Related Products Braycote Braycote Fluoroclean™ HE
Braycote Braycote Fluoroclean™ X-100
Braycote600EF Braycote601EF Braycote602EF Braycote614EF Braycote615
Braycote631A Braycote631RP Braycote640AC Braycote640ACMS
Braycote802RP Braycote803 Braycote803EP Braycote803RP Braycote804
Braycote806 Braycote806RP Braycote807 Braycote807RP Braycote1616
Braycote1624 Braycote1625 Braycote1632 Braycote1636 BraycoteMicronic
Braycote600EF Braycote601EF Braycote700 Braycote701 Braycote803
Braycote1613 Brayco Micronic Braycote815z BraycoteMicrocote® Products
Braycote096 196 296 BraycoVP BraycoteBrayco Base Oils Braycote812
Braycote814 Braycote815z Braycote849 Braycote1624 Braycote1625
Braycote1721 Braycote1721 PLUS Braycote1722 Braycote1723 Braycote1723 PLUS
Braycote1724 Braycote1724 PLUS Braycote1726 PLUS Braycote1727 PLUS
Braycote1728 Braycote1729 BraycoteOptitool 215-2 BaycoteFluoroclean HE
BraycoteFluoroclean X-100 Santovac 5GB Ultra High Vacuum Grease Braycote 600 EF Braycote 601 EF Braycote 602 EF Braycote 614 EF Braycote 615
Braycote 631A Braycote 631 RP Braycote 640 AC Braycote 640 ACMS
Braycote 802 RP Braycote 803 Braycote 803 EP Braycote 803 RP Braycote 804
Braycote 806 Braycote 806 RP Braycote 807 Braycote 807 RP Braycote 1616
Braycote 1624 Braycote 1625 Braycote 1632 Braycote 1636
Braycote Braycote Micronic Braycote 600EF Braycote Braycote 601EF
Braycote 700 Braycote 701 Braycote 803 Braycote 1613 Braycote Brayco Micronic
Braycote Braycote 815z Braycote Microcote® Products Braycote 096, 196, 296
Braycote LVP Braycote Brayco Base Oils Braycote Braycote 812
Braycote 814 Braycote 815z Braycote 849 Braycote 1624 Braycote 1625
Braycote 1721 Braycote 1721 PLUS Braycote 1722 Braycote 1723
Braycote 1723 PLUS Braycote 1724 Braycote 1724 PLUS Braycote 1726 PLUS
Braycote 1727 PLUS Braycote 1728 Braycote 1729
Braycote Braycote Braycote Optitool 215-2
Braycote Related Products Braycote Braycote Fluoroclean™ HE
Braycote Braycote Fluoroclean™ X-100
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