Technical Data Locking Device Notes
TF, TF-KP Series
1. Installing to Keyed Shafts
Mounting to keyed shafts such as motored shafts will reduce the transmissible torque Mt and transmissible thrust Pax by 10%.
- Transmission Torque:Mt × 0.9
- Thrust load :Pax × 0.9
2. Installation accuracy
When a Power-Lock is installed into a straight hub bore, the following is rough indication for the installation accuracy.
(When the hub length is the same as the width of hub and outer ring contact surface )
- Ex:Hub End Face Runout Below 0.002 x r mm
- Er:Outer Hub Diameter Runout Below 0.05mm

3. Hub's Outer Diameter Deformation
When a product is mounted on a hub, contact pressure P' will be exerted on the hub's inner surface, which will cause the hub's outer diameter to experience an elastic deformation.
The specific degree of deformation cannot be determined for it depends on the distribution of P' and the type of hub. However, the following formula can be used to obtain rough deformation values.
△DN ≒ DN E × 2 × K3 × P' ( DN D ) 2 - 1
- P':Hub-side contact pressure MPa
- E:Young's Modulus For steel E = 205800 MPa
- D:Inner Hub Diameter mm
- DN:Hub outer diameter mm
- △DN:Hub's outer diameter deformation mm
- K3:Hub configuration coefficient
(Refer to the major specifications page for each product. )

4. Ambient Temperature
Power-Locks must be operated in an appropriate environment with a temperature ranging from -30℃ to 200℃ .
5. Allowable Deviation of Tightening Torque MA
The allowable deviation from the specified tightening torque MA for locking bolts is ± 5%.
This value guarantees adequate transmissible torque Mt and thrust Pax, and makes adequate allowance for the margin of error that can be expected from appropriate use of a torque wrench.
6. Assembly Lubrication
The main body and bolts of this product must be lubricated during assembly.
Some may be concerned that the lubrication may cause the product to slip or the bolts to loosen. However, specified tightening torque for the bolts is calculated provided that the bolts are thoroughly lubricated. Oil is also required for the tapered surfaces to slide smoothly.
If the unit is not lubricated, transmissible torque will decrease approximately 25% due to a reduction in axial force. The bolts may also deform and lead to failure.
In the case of a stainless steel or an electroless nickel plated model, however, the bolts are coated with a special substance and the main unit is prepared so that it can be operated in the "dry state”. Do not lubricate these models during assembly.
7. Bending moment
The products cannot tolerate bending moments. Contact Tsubaki if a bending moment applies as illustrated below.

8. Outdoor use
The performance of this product is not affected by moisture, such as rain, due to the tight seal of the parts maintained by their high interfacial contact pressure.
However, the exterior surfaces will begin to rust. The rust will reduce the bolts' tensile strengths and cause a sudden drop in the general tightening force.
In order to prevent this, you must use a cover, thoroughly grease the unit and take countermeasures against corrosion.
If the cover causes any inconvenience, opt for the anticorrosive stainless steel or electroless nickel-plated models.