What Is Cobra Solid Lubricant™(CSL)?
Cobra Solid Lubricant™ is a proprietary mixture of graphite and other binding materials formulated specifically for use with bearings. When injected into the bearing, the mixture has the consistency of a paste. After which, a computer controlled pressure and heat treatment is performed followed by a precise run-in and finishing procedure. When the process is complete, the lubricant is dry and the bearing will spin free.
Can It Be Used On All Bearings?
Most ball or roller bearings (except needle bearings and some thrust bearings) as large as 25″ outside diameter or as small as 1/8″ inside diameter can be lubricated with CSL. However, the bearing and its cage should be metal with at least C3 internal clearance. (Note: There are some applications, for example, a typical conveyor wheel, where a full complement bearing can be processed with Cobra Solid Lubricant. In this case, please call to discuss the application.)
How Much Longer Will Bearings Last?
Bearing life is determined by many factors including (but not limited to) load, temperature, RPM, quality of the bearing, shaft fit, housing fit, and lubricant. The degree to which CSL will extend bearing life will vary from one application to another. We have seen applications in which CSL extended the period between bearing maintenance from a daily routine to once every four months – saving thousands of dollars!
How Much Does It Cost?
Cobra Solid Lubricant™ is priced according to the type and size of the bearing used as well as certain conditions of the application.
Can I Buy Tubes Or Containers Of Cobra Solid Lubricant™?
No, because of the special equipment and the proprietary process used to inject and cure the graphite. The bearings can only be processed at UTA’s facility.
Will Cobra Solid Lubricant™ Prevent Corrosion?
CSL is not a corrosion inhibitor. However, it is our experience that even in cases when rust is the primary problem, a measurable bearing life increase was realized with CSL. Normal care should always be taken to protect bearings in corrosive environments.
Is There A Cobra Solid Lubricant™ Product That Can Help Prevent Corrosion?
Yes! CSL-EP (Enhanced Performance) and CSL-EPN ( Enhanced Performance Nano) will each help prevent corrosion due to high temperature oxidation or caustic chemical vapors. CSL-EP and CSL-EPN also provide quieter performance and improved speed capabilities of standard CSL.
Additionally, Cobra Blue used with standard steel bearings may be an alternative solution, if stainless steel bearings are not a viable option for a particular application. Cobra Blue (ferritic nitrocarburizing) offers exceptional corrosion resistance to treated bearings where corrosion is a concern.
What Is CSL-EP?
EP is a unique non-petroleum liquid that is impregnated into CSL. The result is a quiet smooth rotation that improves speed capabilities and helps prevent corrosion due to high temperature oxidation or caustic chemical vapors. The bearing steel will also have a micro thin coating of EP and may feel “wet” or tacky. We carefully selected this non-petroleum product because of its excellent lubricating properties, its tendency to not drip, and because it doesn’t burn like oil or grease so it never leaves a burned carbon deposit on the races.
What Is CSL-EPN?
EPN consists of nano-sized particles of tungsten disulfide (IF-WS2) integrated with the CSL-EP formulation. The nano-sized particles attach themselves to the surfaces of the bearing steel. Because they are spherical in shape and extremely hard, they reduce surface wear, allow for improved speed, run quieter and generally improve performance.
How Often Is Re-Lubrication Required For Bearings When Processed with Cobra Solid Lubricant™?
Never!
An Application Requires Bearings To Operate At Over 500°F. Can Cobra Solid Lubricant™ Be Used?
Cobra Solid Lubricant™ can be used in applications as high as 660°F continuous with momentary peaks several times higher. Because CSL is solid lubricants, the problems normally associated with conventional lubricants (leaking out and carburizing) are eliminated. However, above 300°F, internal clearance greater than C3 and heat-stabilized steel bearings should be considered to improve dimensional stability of the bearing as the steel is heated to high temperatures. Remember, extreme temperatures weaken the bearing steel and will cause a reduction in service life.
How Does It Perform At Very Low Temperatures?
CSL will continue to lubricate even at temperature as low as -150°F because our lubricant is solid. The starting torque is similar to that of a free spinning bearing at room temperature. You can achieve substantial energy efficiency over conventional lubricants and extend motor life (and keep more money in your pocket!).
Can Cobra Solid Lubricant™ Be Used In A Vacuum Application?
Yes! A special formulation of Cobra Solid Lubricant™ (Cobra Solid Lubricant-MoS2) is used in vacuum applications. The result is a product that continues to lubricate yet exhibits extremely low out gassing even in high vacuum and high temperatures. In fact, we have found that, in a vacuum the lubricant continues to be effective even at temperatures beyond our rated upper limit!
Will Cobra Solid Lubricant™ Work Under Water?
Yes! CSL is insoluble in most common organic solvents, acids, and alkalis. The lubricant will not wash out under water, in a steam wash down, or in most chemical baths.
Some Applications Have A Serious Problem With Dust & Other Harsh Contaminants Even Though The Bearings Are Sealed. Will Cobra Solid Lubricant™ Do A Better Job?
This is an excellent application for CSL. The process by which the bearings are lubricated creates a natural seal between the rings. Because the CSL completely fills the gap between the inner and outer rings, only particles smaller than the gap could possibly find their way into the bearing. Also, because CSL is dry, there is little opportunity for foreign matter to attract to or stick to the bearing.
In Some Applications, The Bearings Will Be Exposed To Radiation. All Other Lubricants Deteriorate & May Become Like Varnish In This Environment.
Cobra Solid Lubricant™ will not deteriorate like petroleum lubricants in these applications. You should find greatly extended life for bearings processed with CSL.
The Bearings On A Belt Conveyor Fail Due To Pitting. Can Cobra Solid Lubricant™ Help?
The pitting may be due to static electricity build up on the belt and discharging through the bearing. CSL is electrically conductive and can help prevent the static electricity build up and may solve this problem.
Why Do You Need To Know the Speed of the Application?
Cobra Solid Lubricant™ forms a barrier film on the bearing’s races and rolling elements preventing metal to metal contact. The speed limitations will be lower than with grease or oil. Also, speed affects temperature, load, and service life. Knowing the application speed helps avoid misapplication of CSL and unexpected problems.
Why Do You Need to Know the Temperature of the Application?
Cobra Solid Lubricant™ will perform well in temperatures up to 600°F but the bearing may need extra internal clearance (C4 or greater) above 350°F. Temperature also affects speed, load, and service life. Knowing the application temperature helps avoid misapplication of CSL and unexpected problems.
Why Do You Need to Know Other General Application Conditions (Load, Moisture, Type Of Contaminant, Vacuum, Etc.)?
All of these (and other application conditions) help us provide the best possible improvement to your application’s performance.
Is Cobra Solid Lubricant™ Safe & Acceptable For Use In Food Grade Applications?
Cobra Solid Lubricant™ is NSF H-1 certified as an acceptable lubricant to be used around food processing equipment. However, Cobra Solid Lubricant-EPN & Cobra Solid Lubricant-MoS2 are not listed.
Why Does UTA Recommend Lighter Shaft And/Or Housing Fits Than With Greased Bearings?
Maintaining the internal clearance of the bearing is essential to proper performance. If the shaft or housing fits are too tight, the rolling elements could break through the barrier film causing metal to metal contact and rapid failure.
Why Does UTA Recommend Proper Mounting Procedures?
Proper mounting procedures should always be practiced regardless of the lubricant type. Bearings processed with CSL, however, can be damaged if struck with a hammer during mounting. Improper mounting procedures are sometimes used to “force” a bearing onto a shaft or into a housing that is out of tolerance, out of round, or is ruffed up. This could take up the internal clearance required for CSL and cause the bearing to fail rapidly.
What Happens If I Re-Lubricate The Bearing?
That depends. If it is re-lubed with grease, the barrier coating formed by the CSL will mix with the grease and thicken the grease adding drag to the bearing and causing premature failure. In high temp applications the grease could carburize and again cause failure. If oil is used, the same thing will happen except the thickening may be less destructive.
Can a Bearing Processed With Cobra Solid Lubricant™ Be Cleaned and Put Back Into Service?
Some applications can “gum up” a bearing (printing applications for example) and cause a deterioration of performance that sometimes can be corrected prior to excessive bearing wear. The bearing can normally be cleaned in conventional parts cleaning solutions, dried and reinstalled without any need to re-lubricate.
Why Can’t Needle Roller Bearings Be Processed With CSL?
Our experience shows that Cobra Solid Lubricant™ will only fill the gaps between the rollers. Needle rollers are normally very thin and will likely break providing no lubrication.
Can 2RS & ZZ Style Bearings Be Processed?
Bearings can be processed with CSL as an open bearing or as one Z. In the case of one Z, the bearing is processed from the open side but the second Z cannot be replaced. Seals are not replaced because of the drag (much larger than in a greased bearing).
Are There Any Other Installation Precautions To Watch For Besides Mounting Procedures & Fits?
Yes, be sure nothing touches the graphite since that could affect its rotation and cause skidding of the balls or rollers.
Why Is It Important to Know Failure Mode Or Cause Of Failure Of The Previously Used Lubricant?
Cobra Solid Lubricant™ is a solution product. It is most important to know the problem before a solution can be offered. Often the problem described by the end user is not the root cause of bearing failure.
Why Does UTA Ask What Bearing Life Is Normally Achieved With The Previously Used Lubricant?
It can give an indication of the severity of the problem. It also gives us some insight into if your expectations of CSL , with regards to bearing life and maintenance free performance, are reasonable for the application.
When Processing Mounted Bearings With Cobra Solid Lubricant™, Are There Any Special Modifications Done to the Housing?
The housing is opened up to provide a looser bearing to housing fit. This allows the bearing to follow the shaft through any small misalignment and minimize the affect of driving the balls into the sides of the races. This effect is quite common in applications where the shaft is in an oven and may be bowed. Also, the grease fitting is removed from the housing and the hole gets plugged.
Are There Any Applications That Should Be Avoided Or At Least Looked At With Caution?
Yes. Not recommended applications are (but certainly not limited to): shaker screens, fans, high speed spindles, etc.
Just a Final Note: Although Cobra Solid Lubricant™ is beneficial in so many applications that do not involve high temperatures (freezer conveyors, free spinning, drip free, maintenance free, vacuum, food grade, etc.) high temperature applications are the most frequently seen (it’s just the nature of industry from metal manufacturing, metals forming, tempering, glass manufacturing, paint curing, laminating, drying, etc.) and can be the easiest to show the benefits of CSL. To be sure your expectations of what CSL can accomplish are, some precautions should be considered:
- Bearing steel loses load bearing capacity as temperatures go above 300°F. This characteristic of steel will not change just because of CSL.
- Service life of a bearing is affected by temperature, load, and speed as well as the type of lubricant and other application factors.
- A large differential in temperature between the inner and outer races (i.e. high temperature transmitted through the shaft as on a furnace with the bearings mounted on the outside of the furnace wall) can require larger internal clearance (C4 +) than the surrounding temperature might indicate.
- Shafts that are heated will grow in length and circumference as temperature increases. This growth (or expansion) must be accounted for in order to prevent bearing failure. Some applications will simply not use set screws on one side of the shaft, while others will use a key-way to allow the shaft to move axially through the bore. In either case, the bearing may be affected by the growth, in circumference, of the shaft or the development of corrosion between the shaft and bore preventing the desired affect. When possible, we recommend expansion bearings on one side (and of course proper installation).