slide guide

SLIDE BUSH
LIFE CALCULATION
MOUNTING
Since ball elements are used as the rolling element
in the NB slide bush, the following equation is used
to calculate the travel life.
If the stroke distance and number of strokes per unit
time are constant, the life time is calculated using
the following equation.
Examples of Mounting methods are shown in Figures C-4 ~7.
Figure C-4 Standard Type
L= (
fH・f T・f C
・ C fW P ) 3 ・50 Lh= L・10 3
2・lS・n1・60
using retaining ring
using fixing plate
L: rated life (km) fH: hardness coefficient
fT: temperature coefficient fC: contact coefficient
fW: applied load coefficient C: basic dynamic load rating (N)
P: applied load (N)
*Refer to page Eng-5 for the coefficients.
Lh: life time (hr) lS: stroke length (m)
L: rated life (km) n1: number of cycles per minute (cpm)
LOAD RATING FOR OPEN TYPE SLIDE BUSH
For the open type slide bush an opening is provided to allow the shaft to be supported from underneath. In
case a load is constantly applied in the direction of the opening (for example, being used with a vertical
shaft or an overhang loading is applied), the load rating decreases due to less number of loaded rows of
ball elements. (Table C-8) Therefore, the load rating must be calibrated at the time of design based on the
direction of the loading.
Table C-8 Direction of Load and Basic Static Load Rating
Figure C-5 Clearance Adjustable Type
Figure C-6 Open Type
SLIDE BUSH
part number
SM10G〜16G-OP
KB10G〜16G-OP
SW 8G〜10G-OP
SME(D)10G〜16G
CE(D)16
SM20(G)-OP
KB20(G)-OP
SW12(G)-OP
SME(D)20
CE(D)20
SM25(G)〜100-OP
KB25(G)〜80-OP
SW16(G)〜64-OP
SME(D)25〜30
CE(D)25〜30
SM120,150-OP
loading from above
Load P
Load P Load P Load P
Figure C-7 Flange Type
C C C C
loading from below
Load P Load P Load P Load P
0.64C 0.54C 0.57C 0.35C
※ Excluding all the 3-row steel retainer types. Please contact NB in case of 3-row steel retainer.
C-8 C-9