Ball Screw DFM
Internal Circulation, Flange, Double Nut Type
DFM series is designed for milling, featuring internal circulation, high accuracy and long service life, double nut design provides stability and load-carrying capacity.
Cautions About Use of Ball Screws
Ball screw assemblies are delicate components. Therefore,extra care must be taken to prevent the ball track from damages that caused by edged component or tools. Meanwhile, to prevent steel ball fall out of the nut through the disassembly of screw and nut or over stroke, please be careful while operating. If the steel ball falls out, please contact with TBI MOTION for further instruction. Do not attempt to reassemble, which might cause permanent damage to the ball screw.)
If disassemble is required, please use a transfer pipe which has minor diameter than the screw diameter to transfer the nut to prevent falling out of the steel balls.
Lubrication
Adequate lubrication must be provided when ball screw is used, insufficient lubrication will result in collision of metal, which leads to increase of friction and detrition, thus cause failure or shortening the service life.
Lubricants applied to ball screws can be divided into 2 types, namely lubricating oil and consistent grease. In general speaking, in respect of maintenance, consistent grease will lead to increase of dynamic friction torque linearly along with increase of rotating speed, hence oil lubrication is deemed the better way when speed exceeds 3-5 m/min; however, don’t forget the fact that there have been examples that using grease has been capable of achieving speed of 10 m/min, with respect to the equipment.
In terms of equipments, there are some cheaper lubricant that can be used. In general, to fully utilize the function of ball screw, lubricating oil of 5m/minute is the best option to choose.In figure 1.10.1, we provide the standard of lubricating oil inspection and supplement interval. Before replenishing, please clean up the previous grease to continue.
Table 1.10.1 Inspection of lubrication and interval of refill
|
Method |
Interval |
Check Item |
Replenish or Change Interval |
|
Auto. Periodial oil supply |
Weekly |
Oil level, contamination |
Add at each check, as required depending on tank level |
|
Grease |
Initially 2~3 months |
Contamination on entry of chip |
replenish yearly or according to the inspection result. |
|
Oil bath |
Daily |
Oil level |
To be determined according to consumption |
