The clamping sleeves arranged over a wide basis exert a positive influence on run-out accuracy and rotating flexural stress of the shafthub fit. The degree of torque which can be transferred with two consecutively arranged clamping sleeves is approx. 30 % higher than when using a single clamping sleeve.
This shaft-hub connection is completely free of play and can be released an unlimited number of times. The tightening torque levels for clamping force initiating screws depend on the required clamping force for each individual clamping sleeve.
The sleeve is hydraulically tensioned and precisely centred. Free movement is immediately possible in the un-tensioned state. The axial thrust created during the clamping process with single arrangement of a clamping sleeve is theoretically balanced out in this case by forces working in opposition. In practice, however, in case of a freely located sleeve, allowance must be made for a slight residual thrust as it is not possible to create identical clamping conditions at the clamping sleeves.
This connection is characterized by simple connecting components, a high degree of concentricity and absolute freedom from play.
The hub can be made of an aluminium alloy. Observe the minimum strength specification. High temperatures can impair retention force.
Indexing plate in alloy material at the shaft end of an indexing gear. Here, precise concentricity and run-out are vital.
To satisfy the highest concentricity requirements, we recommend mounting a control facility on the gear to allow the concentricity to be checked and adjusted if necessary.
Here, two long clamping sets are used to achieve high overall radial rigidity due to intensive tensioning of the shaft and hub. The pressure roller is exchanged by pulling the shaft out of the bearings.
Competitiveness through technological leadership – a strategy that calls for an economical increase in power density, efficiency and accuracy. Cylindrical clamping sets create the foundation for this.
Lower Resource Input
- Simple configuration of connecting components.
- Simple installation and dismantling of all components thanks to mating play.
- Minimum axial drag during clamping process.
- Clamping force initiation can be freely configured.
- Quick-release connection.
- High level of concentricity.
- Minimised vibrational excitation.
- High torque levels and axial forces.
- Suitable for alternating torsion.
- Axial and angular position freely adjustable.
- Preserves connecting components.
- Connection can be automated/switched.
Four unique features – numerous benefits
All functional surfaces that determine precision are machined to the finest geometrical and positional tolerances.
- Single-piece design
Unlike tapered clamping sets, the single-piece steel body does not have any joints that could compromise tolerances. This ensures that the high degree of precision achieved in the manufacturing process can also be brought to bear in the relevant application.
When subjected to axial compression, the unique geometry of the absolutely symmetrical base body ensures uniform transverse contraction in the direction of the shaft and hub. The resulting centring effect is equivalent to that of the hydro-expansion principle, only much simpler, safer and stiffer.
Cylindrical clamping sets exert very low levels of wear on their connecting components. Significantly better clamping homogeneity at the contact surfaces eliminates any possibility of peak clamping force acting at specific points, which frequently lead to damage and installation problems. At the same time, the Spieth design in the tensioned state is equivalent to the combination of a knee lever and a spring compressed against a block, thus guaranteeing an extremely rigid connection. And when released, the cylindrical clamping set easily returns to its original shape.
Shown here is the using of a clamping set from series DSK with an integrated clamping screw.
The principle is illustrated in a simplified diagram with enlarged play.
- Transmittable Forces
The specifications provided in the table apply to a bore tolerance of H7 and a shaft tolerance of h5 in the connecting components. For an h6 shaft, in the most unfavourable scenario, a reduction of transmittable forces of approx. 10 % may be expected.
The specifications provided in the table apply to a bore tolerance of H7 and a shaft tolerance to DIN 748 (k6/m6).
M: Transmittable torque at Fa = 0
The specified values were ascertained in a series of tests, in which the connecting components were made of C45 steel, produced with the stipulated surface quality.
Fa: Transmittable axial force at M = 0
The Fa values are calculated according to
Subjection of the clamped connection to steady, pulsating, alternating or sudden stress has no impact provided that the occurring peak forces do not exceed the catalogue values. The risk of fretting corrosion is always a possibility in friction-locked connections subjected to alternating torsion or rotating bending stress. This phenomenon can complicate dismantling and can be prevented by complying with the following instructions:
M and Fa:
If both torque and axial forces act on a clamping set at the same time, check using the following formula whether the resulting torque Mr is transmittable.
M = Transmittable torque (catalogue value) [Nm]
Me = Required torque [Nm]
Mr = Resulting torque [Nm]
Fae = Required axial force [N]
d1 = Shaft diameter [mm]
F: Maximum permissible clamping force
To avoid the danger of fatigue failure and fretting corrosion, the clamping sleeves should be tensioned in case of high clamping/release cycle frequencies to a maximum of 0.75 F.
C: Required functional installation space
Spieth clamping sleeves must be clamped using the controlled application of force. The clamping force cannot be applied in relation to the clamping path. To prevent premature blocking, a "free" functional path "C" must be provided.
In the case of automated operation, for example, using hydraulic actuation, a variety of influencing variables can cause the actual values of the system to deviate from the catalogue values. For this application scenario, we strongly recommend that you verify the force or torque values required. In this application, care must be taken to ensure that the installation is completely free of axial play. To avoid fatigue failure and due to the danger of fretting corrosion, in case of high clamping/release cycle frequencies, the clamping sleeves should be tensioned at a maximum of 0.75xF.
If it is not possible to apply the clamping force F, the following formula is used for approximate determination of the torque Mred which can be transmitted with the given clamping force Fgiv. (<F).
To ascertain the necessary clamping force for a transmittable torque Mred < M an approximation is possible using the following formula:
|Diameter in mm||Clamping initiation||Transmittable forces|
1) Max. perm. clamping force. For automated operation, the clamping sleeve should be clamped with max. 0.75xF.
2) Design specification, not to be confused with actuation travel. For explanations, see p. 55.
3) d2 > 80 mm = Concentricity to IT4
We are here to help you | Our team is looking forward to your task. Contact us. We make the right solution for your requirements a reality.
Phone +49 (0) 711 / 930730-0
Fax +49 (0)711- 930 730-7