Roller Kelly Bushing
 

The Roller Kelly Bushing is an essential drilling tool, can be equipped with
turntable slips, so as to drive Kelly bar. The tool reduces its friction with 
Kelly bar by the rolling of four rollers in order to prolong its life. As for the 
square or hexagon Kelly bar, they connect with all kinds of turntables 
by changing roller, with two drive methods, namely, square rolling and pin 
shaft rolling. The Roller Kelly Bushing is simple in operation, convenient 
in installation and perfect in safety performance. It can be applied to rotary 
table from 17 1/2” to 49 1/2”.

 

Construction

 

The Roller Kelly Bushing consists of top cover, base, axis, needle bearing, 
sealing body, roller, binding bolt, and refuel cup. The needle bearing within 
the roller is being installed on axis which both ends compact between top 
cover and base. There is interval 3mm between top cover and base, in order 
to give full play to pressing force formed by four big kingbolts M38. The refuel 
cup lying on axis end injects grease into needle bearing at regular intervals. 
In order to prevent the sealing body from penetrating and protect the needle 
bearing, the inner-outer O type circle must be installed on the both ends of 
the roller. Fasten pin lying on the top of sealing body prevents it from rotating,
and inlays inside seam allowance of up base.