Tag Archive: rolling bearings

1. Levels of Precision: Choose the Right Bearing to get the Best Life for Your Application…

   November 2, 2015 4:43 pm Leave a Comment

   At Action Bearing we are fully dedicated to our customers, and take pride in making outstanding products as well as providing accurate documentation of their performance. Our bearings are engineered and manufactured with the highest levels of precision, and uphold the highest quality standards, however, no bearing lasts forever. So how can you be sure that your bearing will perform well throughout its life?

   Rolling element bearings are known for being extremely reliable, and many even outlive the machines on which they are installed.  However, several factors can shorten a rolling element bearing’s life, and load and speed are the most common causes for early failure. A load that exceeds the bearing specification can accelerate fatigue, shorten its life up to a factor of 8-10, and a speed exceeding the veering specifications can also dramatically decrease a bearing life. Other factors like extreme temperatures, vibrations, and dirt or contaminants play an important part in a bearing’s life.

   Nevertheless, if a bearing was selected correctly and used for the correct application, it will surely last for the specified lifetime (and probably longer).  Listed below are approximate values for bearing life (measured in operating hours) that you can expect for different applications: 

   • Hobbyist’s power tools: 100-150 hr
   • Professional power tools: 100-1000 hr
   • Household appliances: 200-3000 hr
   • Agricultural machinery: 500-5000 hr
   • Tractors: 5000-12000 hr
   • Cars and trucks: 800-10000 hr
   • Trucks generally have a longer bearing life by design than cars
   • Hydraulic systems: 1000-20000 hr
   • Bearings in stationary hydraulic systems generally outlast bearings in mobile hydraulic systems
   • Office and data processing machinery: 1200-16000 hr
   • Material handling equipment: 2000-18000 hr
   • Rolling mills: 2000-20000 hr
   • Compressors: 3000-20000 hr
   • Building material machinery: 5000-50000 hr
   • Crushers: 13000-40000 hr
   • Extruders: 20000-50000 hr
   • Industrial gearboxes: 20000-50000 hr
   • Textile machinery: 20000-70000 hr
   • Printing presses: 35000-100000 hr
   • Paper machinery: 75000-150000 hr

   Action Bearing is here to help you get the most out of your bearings.  For years our experienced team has been providing high quality bearings across a large span of different industries. Consult with us, and we’ll make sure your bearing lives a long, full, productive life.  For more information on which kind of bearing is best for you, visit our Catalog and Technical Toolbox web pages.

2. Levels of Precision – Choose Wisely: How Fast Your Bearings Need To Go

   4:43 pm Leave a Comment

   A rolling bearing is composed of: two rings – known as the inner and outer race – separated by a set of rolling elements, which are most often kept at a relative distance by a cage. At its most basic level a rolling bearing decreases rotational friction and supports radial and axial loads. Each element is manufactured to a certain tolerance, and the sum of the geometrical and form tolerances determines, loosely speaking, the level of performance of the bearing – rating the load it can carry axially and/or radially, the limiting speed, noise, etc.

   

   For a long time, only bearings with wide tolerances could be mass produced, nowadays, however, technology has advanced dramatically and parts can be manufactured with very tight tolerances, to produce extremely high performing bearings routinely.

   So how do I know if a bearing has a wide tolerance or a tight tolerance?

   The Annular Bearing Engineering Committee (ABEC) created a rating system that has become the industry standard for ball and roller bearing tolerances. ABEC includes five tolerances classes: 1, 3, 5, 7, and 9 with 1 being the widest and 9 the tightest. Thus, bearings with a higher ABEC rating have tighter tolerances, and that means better precision, higher efficiency, and the potential to accommodate applications requiring high speeds.

   It is important to note that a bearing in a higher ABEC class does not imply that the bearing can carry a higher load, rather it can carry the same load as an analogous bearing with a lower rating but at higher speed, thanks to its more controlled runout and smaller endplay. ISO has an equivalent standard (ISO 492) for bearing tolerances that corresponds to the ABEC ratings as follows: normal class 6x (tightest), 6, 5, 4, and 2.

   The ABEC tolerance classifications specify both tolerances of size and form for the individual inner and outer rings. The critical features of the rings include the bore (or inner diameter of the inner ring), the outer diameter of the outer ring, the ring widths, and the raceways of each ring. Tolerances of form include roundness, taper, runout, and parallelism.

   And how do I know if I need an ABEC 7 bearing or an ABEC 3 for my application?

   In general a bearing is a very precise mechanism, and the design specifications are the main driver for choosing one. In fact, selecting a bearing with a tolerance too loose for the application can impact the maximum amount of torque that it can withstand or cause an imbalance of the load at high speed, and ultimately impact its life span. Conversely, a bearing with a tolerance that is too high for the application will probably perform better, but will also cost significantly more.

   The vast majority (more than 98%) of ball bearings sold every year belong to the ABEC 1-3 classes –  with tolerances that are down to the 4^th decimal place! – and can satisfy the vast majority of applications. Bearings in higher classes, called high/super/super high/ultra-precision (falling into ABEC 5,7,9 classes), have much tighter tolerances, that require more precise machining and longer production times. These bearings are available in more limited supply and have prices 4-5 times higher than ABEC 1-3 bearings.

   Specifically, thanks to its smaller runout and axial play, an ABEC 7 bearing will perform better and last longer in high speed applications, than an ABEC 3 rated bearing. So, if you need a super precise, long-lasting bearing, ABEC 7 is probably the bearing for you. Applications for highly rated ABEC bearings include Machine Tools, Aerospace, Medical devices and more.

   Conversely, if your application doesn’t require extremely high tolerances, an ABEC 1-3 bearing is probably the better choice. For example, ABEC 1-3 rated bearings are used in automotive, electric motors, gear boxes, and most industrial applications.

   In ultimate analysis, when choosing a bearing based on its ABEC rating, always keep in mind the scope, carefully consider your design specifications (how fast is this going to go?!), while keeping in mind the desired lifespan. Weigh these considerations against the cost/performance trade-offs of the standard and select the bearing that is best suited for your application.

   At Action Bearing, we know that choosing the right bearing is essential to your success. We have years of experience providing high quality bearings to many different Industries, and our technical team is here to help you choose the right bearings for your application. In addition, our Catalog and Technical Toolbox webpages include information that can help accelerate your decision-making process.

   If you have any questions, feel free to contact us today; we’re happy to help you select the most appropriate bearing for your needs.

   
   
   
   
   
   
   

3. Rick Piracini Leads Printing Division

   4:38 pm Leave a Comment

   The printing market has made a comeback.

   Due to the increased demand, we’ve created an entire division to specifically cater to prepress, offset, digital printing and paper converting markets.

   Our expert team, led by Rick Piracini, helps determine which bearing technologies would be most suitable by taking into consideration the specifications, recommendations, maintenance strategies, fatigue life and wear resistance of the bearing in relation to the application.

   

   Printing

   To achieve the required pin sharp quality, we provide high precision and wear free bearing supports for print rollers. This ensures that the impression cylinder is supported with as little clearance, as much rigidity as possible, and with very few runout errors.

   The NAO style needle bearing with offset cage packets has become the standard. Needle rollers, Cam Followers and yoke rollers are used extensively in the distributor roller drives, gripper shaft controls and throughout the presses.

   Other related products available include: ball bearings, needle bearings, roller bearings, linear motion, free running, mounted units, oil seals, cam followers and rod ends.

   Paper Converting

   The process of converting paper into a usable form has very different bearing requirements. Slitters and rewinders require high speed ball bearings and linear motion bearings that have high running accuracy.

   We provide special solutions to printing and paper converting clients such as the use of “free running” insert bearings and pillow blocks. These have modified seals and slingers on both sides, which allow for low start up torque and effective sealing even in high heat applications.