Pages Design Considerations A-2 > to A-16 > A , LBOA , LBC , LBO , LBCM , SLBC , SLBO , DLBC , DLBO > & TRCA > series ( Linear Bearings and Carriage Assemblies ) B-1 > to B-14LBCA > B , SN , SM , ES , ARS , LSRS , SA > & TRSA series > ( Shafting, Supports & Shaft Assemblies ) C-1 > to C-26SL,SS > C

ECH offers "Cut to length" steel and stainless steel shafting. English shafting is available in "class" L, S and N diameter tolerances. 1060 Carbon steel shafting is available from 0.25 to 2.00 inches. Metric diameter size range is 8 to 50 mm. 440C stainless steel shafting is available from 0.25 to 2.00 inch diameters. Any length is available within .001 inch increments, up to the standard maximum stocked lengths. There is a SL-PD (pre-drilled) option which offers ready to mount shafts to the ARS or LSRS component supports. Any shaft can also be machined per drawings which are supplied by the...

ECH 's LBCA & LBOA offer an "all steel" design. This provides for operation in high temperature environments (up to + 600 > o A F). These bearings have a working bore diameter that corresponds to > ECH 's SS shafting (class S). This bearing style can offer a smoother operation as compared to the LBC & LBO style for some applications. > ECH 's linear bearings have a ball conforming outer race coupled with a self-aligning feature which allows for zero bearing clearance while maintaining smooth operation. The independently self-aligning outer bearing races insure smooth operation by allowing miss-alignment...

Shafting is available in diameter tolerance "class" L, S, and N. Metric shaft diameters (SM) are a standard option also. system friction, while maintaining an optimal surface nish. > shafting, SA and TRSA shaft assemblies use Rockwell 60-65C hardened and ground shafts. These high quality carbon steel shafts are accurately machined and heat treated for uniform hardness. They are also inspected for straightness, roundness, and smoothness. The high hardness and extremely smooth surface of the steel shafts creates an abrasion-resistant surface, which reduces material wear and > ECH shaft assemblies...

Retention PinLinear BushingIntegral Wiper Seal Pillow Block > Preload Adjusting Screw "Outer Race"Linear BushingRecirculatingSteel Balls Steel Bearing Plate "Inner Race" Steel Shaft Steel Bearing Plate "Inner Race" Steel Shaft Longitudinal Grove Recirculating Steel Balls Steel Bearing Plate Ball RetainerLinear Bushing .5 Self-Aligning in all Directions > Linear Bushing >

with a 10 inch move out, then back 10 inches every 90 seconds for 8 hours per day for > and 50 weeks per year (24 x 2) inches (10 x 2) inches 90 secX60 sec 1 minX60 min 1 hrX8 hr 1 dayX5 days 9,590,400 1 weekX50 weeks 1 yrX6 years= inches of travel assembly needs to last 6 years > with (24) 1 inch moves out, then back 24 inches every 30 seconds > for 12 hours per day for 7 days per week and 52 weeks per year 30 secX60 sec 1 minX60 min 1 hrX12 hr 1 dayX7 days 201,277,440 > 1 weekX52 weeks 1 yrX8 years= inches of travel assembly needs to last 8 years >

Even though the forces acting upon a bearing or carriage assembly can be calculated, other parameters such as chang- ing loads, speeds, acceleration rates, environments, and lack of lubrication produce extra forces (stresses) that are hard to quantify. As a bearing moves, there are additional resultant loads as a by-product. The rate at which the bearing begins to move a load can have a large impact on its life. The linear bearings see this start/stop rate as a shock load each time. These and other variable loads cannot be calculated precisely. Thus, a safety factor should be applied to account...

or aking will occur under normal operating conditions. > H T The maximum travel life of a linear bearing is achieved when the shaft surface has a hardness value greater than (>) Rockwell 60C. This hardness assures that no shaft grooving Ambient temperatures over 212 > F (100 > C) will fatigue the linear bearings, or carriage assembly, and will cause a de- crease in travel life. > ECH 's linear bearings or carriage assemblies have a maximum operating ambient temperature of 185 > F. Therefore these bearings, or carriage assemblies, should never be used in ambient temperatures above 185 > > ECH...

Load Centered on Carriage The dynamic load capacity of a > ECH TRCA carriage assembly is based upon having the load forces centered on the carriage and the combined dynamic load capacity values of the SLBO or DLBO linear bearings used. The rated values are based on a L F A > LoadLoad 10 life of 2 million inches of travel (or 50 km) and with the load forces applied downward onto the car- riage assembly. For a given carriage assembly, as the load force de-creases, the life of the carriage assembly will increase exponentially. The life of a carriage assembly, used in an application, can be determined...

d > 1 - distance between center lines of shafts or rails(in) d > 2 - distance between center lines of linear bearing blocks(in) d > 3 - distance between carriage center and load center of gravity(in) d - distance between carriage center and load center of gravity(in) > 4 d > r - distance between carriage surface and linear bearings(in) F > BX - force acting upon bearing in X-axis direction(lbs) F > BY - force acting upon bearing in Y-axis direction(lbs) F > BZ - force acting upon bearing in Z-axis direction (lbs) W - load weight (lbs) > F > avg - average force acting upon bearing(lbs) F > min...

The following example is provided to aid in understanding how the various charts and equations are implemented. For this example, the life estimation will be determined for an application that will use a Some applications may require a custom option from > ECH . By utilizing a custom carriage length which has (6) SLBO-12, it would increase the R value to 2,820 lbs. The L life estimate would then become 98,538,824 inches. Another option would be to utilize chrome plated shafts for the TRSA assembly which will increase the hardness to 67 - 72 Rc. Thus, the hardness factor will become 1 from the...