Product information
>
Ball Screw
>
Positioning Ball Screw
>
Model BNT
Model BNT
Dimensional drawing
Model No.
Screw
shaft
outer
diameter
d
Lead
Ph
Ball
center-to-
center
diameter
dp
Outer
diameter
D
g6
Flange
diameter
D
1
Overall
length
L
1
Basic load rating
Detail specifications
CAD
Dimensional drawing
Dynamic
rating
Ca
Static
rating
C
0
a
2D
(DXF)
3D
mm
mm
mm
mm
mm
mm
kN
kN
BNT 1404-3.6
14
4
14.4
—
—
35
6.8
12.6
BNT 1405-2.6
14
5
14.5
—
—
35
7.2
12.6
BNT 1605-2.6
16
5
16.75
—
—
36
7.8
14.7
BNT 1808-3.6
18
8
19.3
—
—
56
18.2
34.4
BNT 2005-2.6
20
5
20.5
—
—
35
8.7
18.3
BNT 2010-2.6
20
10
21.25
—
—
58
14.7
27.8
BNT 2505-2.6
25
5
25.5
—
—
35
9.6
23
BNT 2510-5.3
25
10
26.8
—
—
94
43.4
92.8
BNT 2806-2.6
28
6
28.5
—
—
42
10.1
25.8
BNT 2806-5.3
28
6
28.5
—
—
67
18.3
51.6
BNT 3210-2.6
32
10
33.75
—
—
64
27.3
59.5
BNT 3210-5.3
32
10
33.75
—
—
94
49.6
118.9
BNT 3610-2.6
36
10
37
—
—
64
28.7
65.6
BNT 3610-5.3
36
10
37
—
—
96
52.1
131.2
BNT 4512-5.3
45
12
46.5
—
—
115
68.1
186.7
Description
*
Descriptions are pdf files.
Overview of THK Ball Screws
Point of Selection
Flowchart for Selecting a Ball Screw
Accuracy of the Ball Screw
Lead Angle Accuracy
Accuracy of the Mounting Surface
Axial Clearance
Preload
Selecting a Screw Shaft
Maximum Manufacturing Length of the Screw Shaft
Combinations of Shaft Diameter and Lead for the Precision Ball Screw
Combinations of Shaft Diameter and Lead for the Rolled Ball Screw
Method for Mounting the Ball Screw Shaft
Permissible Axial Load
Permissible Rotational Speed
Studying the Caged Technology
Types and Features
Selecting a Nut
Types of Nuts
Selecting a Model Number
Calculating the Axial Load
Static Safety Factor
Studying the Service Life
Studying the Rigidity
Axial Rigidity of the Feed Screw System
Studying the Positioning Accuracy
Causes of Error in the Positioning Accuracy
Studying the Lead Angle Accuracy
Studying the Axial Clearance
Studying the Axial Clearance of the Feed Screw System
Studying the Thermal Displacement through Heat Generation
Studying the Orientation Change during Traveling
Studying the Rotational Torque
Frictional Torque Due to an External Load
Torque Due to a Preload on the Ball Screw
Torque Required for Acceleration
Investigating the Terminal Strength of Ball Screw Shafts
Studying the Driving Motor
When Using a Servomotor
When Using a Stepping Motor (Pulse Motor)
Features of Each Model
Overview of THK Ball Screws
Positioning Ball Screw
Standard combinations of outer diameters and leads of the screw shafts
Dimensional Drawing, Dimensional Table
Model BNT
Ball Screw Peripherals
Support Unit Models EK, BK, FK, EF, BF and FF
Structure and Features
Type
Types of Support Units and Applicable Screw Shaft Outer Diameters
Model Numbers of Bearings and Characteristic Values
Example of Installation
Mounting Procedure
Types of Recommended Shapes of the Shaft Ends
Dimensional Drawing, Dimensional Table
Model EK Square Type Support Unit on the Fixed Side
Model BK Square Type Support Unit on the Fixed Side
Model FK Round Type Support Unit on the Fixed Side
Model EF Square Type Support Unit on the Supported Side
Model BF Square Type Support Unit on the Supported Side
Model FF Round Type Support Unit on the Supported Side
Recommended Shapes of Shaft Ends - Shape H (H1, H2 and H3) (For Support Unit Models FK and EK)
Recommended Shapes of Shaft Ends - Shape J (J1, J2 and J3) (For Support Unit Model BK)
Recommended Shapes of Shaft Ends - Shape K (For Support Unit Models FF, EF and BF)
Nut Bracket (Model MC)
Structure and Features
Type
Dimensional Drawing, Dimensional Table
Nut Bracket
Lock Nut (Model RN)
Structure and Features
Type
Dimensional Drawing, Dimensional Table
Lock Nut
Options
Contaminaton Protection
Lubrication
Corrosion Resistance (Surface Treatment, etc.)
Contamination Protection Seal for Ball Screws
Wiper Ring W
Canvas seal CC
Dust Cover for Ball Screws
QZ Lubricator
Dimensions of Each Model with an Option Attached
Dimensions of the Ball Screw Nut Attached with Wiper Ring W and QZ Lubricator
Ball Screw Nut Dimensions with Canvas Seal
Specifications of the Bellows
Model No.
Model Number Coding
Notes on Ordering
Precautions on Use
Precautions on Using Options for the Ball Screw
QZ Lubricator for the Ball Screw
Features and Types
Features of the Ball Screw
Driving Torque One Third of the Sliding Screw
Examples of Calculating Driving Torque
Ensuring High Accuracy
Capable of Micro Feeding
High Rigidity without Backlash
Capable of Fast Feed
Overview of THK Ball Screws
Point of Selection
Accuracy of the Ball Screw
Example of calculating the preload torque
Studying the Positioning Accuracy
Example of considering the rigidity of a feed screw system
Examples of Selecting a Ball Screw
High-speed Transfer Equipment (Horizontal Use)
Vertical Conveyance System
Mounting Procedure and Maintenance
Mounting Procedure
Installing the Support Unit
Installation onto the Table and the Base
Checking the Accuracy and Fully Fastening the Support Unit
Connection with the Motor
Maintenance Method
Amount of Lubricant
Precautions on Using Options for the Ball Screw
QZ Lubricator for the Ball Screw