Will quality from China meet my requirements? Who are ESL Bearing customers? what are some applications where ESL Bearings are used? What is the nomenclature for Precision Bearings (P4, P5, Tolerances)? What is/are the standard greases? What is good high temperature grease? What does CE or C0 fit mean? What does V1 mean at the end of the deep groove ball bearing nomenclature? What does U3A mean at the end of the deep groove ball bearing nomenclature? Does internal clearance effect the bearing precision (C3 vs P3)? Which grease is best suited for most general bearing? Load ratings seem to vary from manufacturer to manufacturer, is there a single method that can be used to compare like styles of bearings? What factors should be considered when choosing a bearing? How much grease is too much? Explain the difference between C3 and normal clearance? What does the term "electric motor quality" mean? Where are specific bearing types manufactured, plant by plant? What bearing types does ESL consider their strong points? What is preload? What is the difference between LLB & LLU seals? Is it safe to use a C3 fit in place of a standard fit? What grease can be used when performing maintenance on mounted units? What is the difference between ABEC 3 and C3? Does the fit get better going up to C4 or down to C2? Will quality from China meet my requirements? There are many levels of quality in the bearing industry in China. ESL Bearing produces bearings of similar quality and standards as the leading producers in Japan, Europe and the US. ESL Bearing uses ball cages and retainers produced by the same companies that sell component parts to NSK, SKF, NMB and NTN. Who are ESL Bearing customers? ESL Bearing is in the business of producing medium to high volume bearings for Original Equipment Manufacturers (OEMs). What are some applications where ESL Bearings are used? ESL bearings are used by leading manufacturers of power tools, household appliances, lawn and garden equipment, computers, electric motors and automobiles. What is the nomenclature for Precision Bearings (P4, P5, Tolerances)? ESL follows the ISO precision tolerance classes of P0, P6, P5, P4 and P2 which are equivalent to ABMA classes ABEC 1, ABEC 3, ABEC 5, ABEC 7 and ABEC 9. What is/are the standard greases? Open Bearing are supplied lubricant with Shell AF2 or Exxon Unives J-13 rust preventative lubricants. Ball bearings with two shields(-ZZ) or two seals(-2RS) are supplied with Chevron SRI#2 or Mobil 28grease as standard and are ready to use. Upon request ball bearings can be lubricated with other greases or oils to any specifications. What is good high temperature grease? ESL has close to 700 greases listed. To pick one for a specific application requires more application information. What does CE or C0 fit mean? These are competitor terms for electric motor and normal internal clearances. Clearance does not indicate any type of fit. What does V1 mean at the end of the deep groove ball bearing nomenclature? For ESL "V1" stands for the first variation on this basic part number. This suffix lettering does not indicate any specific features. A print will have to be reviewed to see what is not standard. What does U3A mean at the end of the deep groove ball bearing nomenclature? In a part number like 6313ZZC3/2AU3A the "U3A" can be a packaging code or specific customer identification code. This does not affect the bearing features. Does internal clearance effect the bearing precision (C3 vs P3)? C3 is an internal clearance, or the amount of internal free space between the rolling elements and the raceways of a bearing. P3 does not exist. P6 is an ISO tolerance class equivalent to ABEC 3, or the accuracy the bearing is manufactured to. Clearance does not affect tolerance and tolerance does not affect clearance. Which grease is best suited for most general bearing? The current ESL standard grease for unknown aftermarket applications is 5C (Chevron SRI 2). In most cases a good general purpose lithium or polyurea based grease will work. Load ratings seem to vary from manufacturer to manufacturer, is there a single method that can be used to compare like styles of bearings? Load ratings don't really vary from among manufacturers, the methods used to calculate load ratings is different. Some manufacturers use the ABMA standard, some use the US Industry standard, some use equivalent dynamic load calculations. In general if the internal design is the same the load ratings will be equivalent. What factors should be considered when choosing a bearing? All application data (loads, speeds, orientation, etc.), intended use, and environment. How much grease is too much? For general applications a grease fill of 30% of the free space in the bearing seems to be accepted as standard by most manufacturers. Slow speed applications in harsh environments (such as agricultural machinery) can sometimes require a larger fill. High speed applications (ie. hand tools) can require a lesser fill. Check with ESL engineering for any special requirements. Explain the difference between C3 and normal clearance? Clearance classes are established by the ABMA. C3 is a clearance specification one class larger than "C Normal" sometimes referred to as "C0" in deep groove radial ball bearings. What does the term "electric motor quality" mean? The term "electric motor quality" is freely used in describing bearings that meet a perceived "higher" level of quality than the standard ABEC1 bearing. Contact ESL marketing for an Electric Motor Quality brochure. Where are specific bearing types manufactured, plant by plant? Due to the size of ESL, the answers to this are too numerous to list. Contact ESL engineering for specific bearing inquires. What bearing types does ESL consider their strong points? Contact the ESL Marketing department. What is preload? Preload is an initial load or "negative clearance" given to a bearing during before operation. This results in the rolling element and raceway surfaces being under constant elastic compressive forces at their contact points. This has the effect of making the bearing extremely rigid so that even when load is applied to the bearing , radial or axial shaft displacement does not occur. What is the difference between LLB & LLU seals? The "LB" seal is a non-contact seal for reduced torque or higher speed requirements. The "LU" seal is contact seal for better grease contamination control, but the contact friction increases torque and lowers the limiting speed. Is it safe to use a C3 fit in place of a standard fit? C3 is not a fit, it is an internal clearance. Fit is how tight or loose the shaft and housing hold the bearing in place. In most electric motor rebuild applications a C3 clearance can be used in place of a normal clearance. Contact ESL engineering for other applications. What grease can be used when performing maintenance on mounted units? Standard bearing unit inserts are prelubed with a lithium based (Shell Alvania 3) grease. Relube should be a grease with the same base (lithium). What does each grease code identify? The grease code on a bearing number tells us the manufacturer, type and quantity. What is the difference between ABEC 3 and C3? Does the fit get better going up to C4 or down to C2? ABEC 3 is an AMBA tolerance class. C3 is an internal clearance specification. Fit is the relationship between the bearing bore and outside diameters to the housing bore and shaft outside diameter. Tolerance, clearance and fit are independent dimensions, although in some cases choosing a larger internal clearance can allow you to use a tighter interference fit. Please Contact ESL engineering for details. PROBLEM | CAUSE | REMEDY | Noise | High pitched metallic | Poor lubrication | Improve lubrication | Clearance too small | Correct clearance | Poor fitting | Investigate mounting method and seating | Excessive load | Examine shaft and housing tolerances for closing effect | Low pitched metallic | Brinelled raceway | Avoid shock loads | Regular | Rust or damage | Check & replace seals & relubricate | Flaking of raceway surface | Improve lubrication & check fitting, clearance and fixing method | Irregular | Ingress of foreign matter | Check & replace seals and relubricate | Excessive clearance | Correct clearance | Damage & flaking of rolling element | Reduce loads and/or clearance | Variable | Varying clearance due to temperature changes | Check fits taking housing material and temperature into consideration | Damage to raceways | Improve lubrication & check fitting, clearance and fixing method | Heavy vibration | Flaking of raceway and rolling element | Improve lubrication & check fitting, clearance and fixing method | Ingress of foreign matter | Check & replace seals and relubricate | Excessive clearance | Correct clearance | Poor location | Ensure abutment face and fitting diameter are perpendicular | Excessive heat generation | Clearance too small | Correct clearance | Poor location | Ensure abutment face and fitting diameter are perpendicular | Excessive load | Examine shaft and housing tolerances for closing effect | Poor lubrication | Improve lubrication | Creep | Maintain recommended shaft & housing fits | Lubrication breakdown | Too much grease | Use correct lubricant quantity | Ingress of foreign matter | Check & replace seals and relubricate |
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