Description
TS7Z75×120 Locking Assembly – 75mm Shaft 120mm OD Keyless Rigid Shaft-Hub Connector
The TS7Z75×120 serves 75 mm shaft connections in large industrial drives with a rated torque of 2.12 kN·m and axial capacity of 91 kN. Typical applications include large centrifugal compressor impeller hubs, high-power fan drives, and offshore pump shaft connections where the locking assembly’s keyless design eliminates keyway fatigue at high power density. For a complete listing of all TS7Z locking assembly models, visit our product catalog.
The TS7Z locking assembly operates on the principle of tapered ring compression: two tapered steel rings — inner and outer — are drawn together axially by the clamping screws. The taper geometry converts axial screw preload into a radial clamping force, expanding the inner ring against the shaft surface and contracting the outer ring against the hub bore simultaneously. The resulting surface pressure — 47 MPa for the TS7Z75×120 at the specified M_a of 84 N·m — generates a friction connection that transmits both torque (Mt = 2.12 kN·m) and axial force (Ft = 91 kN) without any mechanical interlock element. No keyway is required in either the shaft or the hub bore.
The elimination of the keyway is the principal engineering advantage of the TS7Z over traditional keyed hub connections. A keyway introduces a stress concentration at its corners that can initiate fatigue cracks under the cyclic torsion loading of a rotating drive — particularly at high surface hardness or in applications with frequent torque reversals. The TS7Z distributes torque loading uniformly around the full circumference of the shaft bore, eliminating this stress riser and significantly extending the fatigue life of the connected shafts. For high-cycle, high-torque drives — mills, fans, compressors, and crushers — this durability improvement is a primary selection rationale.
Technical Specifications
| Parameter | Value |
|---|---|
| Model | TS7Z75×120 |
| Type | Locking Assembly (Keyless Shaft-Hub Connection) |
| Shaft Bore (d) | 75 mm |
| Outer Diameter (D) | 120 mm |
| Rated Axial Force (Ft) | 91 kN |
| Rated Torque (Mt) | 2.12 kN·m |
| Surface Pressure (Ps) | 47 MPa |
| Installation Screw Torque (Ma) | 84 N·m |
| Mass (G) | 3.8 kg |
| Material | Steel |
| Standard | GB/T 5106 compatible |
Dimensional Reference
Structural Cross-Section
Installation and Design Guidance
Installation of the TS7Z75×120 requires the shaft surface to be clean, dry, and within an h6 or k6 shaft tolerance, with a surface finish of Ra 0.8–1.6 μm. The hub bore should be machined to H7 tolerance. Clamping screw threads and head bearing faces must be lubricated with MoS₂ paste before installation to ensure the M_a = 84 N·m tightening torque produces the correct clamping force. Tighten all screws in a star pattern in at least three progressive passes — do not fully tighten one screw before the others.
To verify shaft material suitability, check: Ps (47 MPa) ≤ 0.9 × shaft yield strength. For C45 steel (yield ~370 MPa): 0.9 × 370 = 333 MPa > 47 MPa — acceptable. For aluminium alloy 6061-T6 (yield ~275 MPa): 0.9 × 275 = 247 MPa; compare with 47 MPa for this model. If the shaft material yield strength is insufficient, contact our contact our team for a re-rated configuration.
Keyless Design
No keyway in shaft or hub. Eliminates keyway stress concentration and fretting wear. Angular position can be set freely — no keyway angular constraint.
Self-Releasing Disassembly
Back off clamping screws in a star pattern — the taper geometry produces a self-releasing action requiring no extraction tools or heat. Shaft and hub surfaces are undamaged after removal.
Uniform Load Distribution
Torque is transmitted through friction uniformly around the full shaft circumference, distributing stress evenly and enabling the same torque to be carried at lower peak shaft stress than a keyed connection.
Bidirectional Torque
Frictional connection transmits equal torque in both rotational directions. No directional constraint — suitable for reversing drive applications without additional design consideration.
Customer Reviews and Case Studies
★★★★★
Brazil — Steel Rolling Mill
Fitted the TS7Z75×120 on hot strip mill coiler mandrel drive connections. Temperature in this area reaches 60°C; the locking assembly’s static friction connection is unaffected by thermal cycling where a keyed connection would develop fretting wear over time. The 47 MPa contact pressure distributes the load evenly around the shaft circumference.
— Engineering Manager, São Paulo
★★★★★
Turkey — Automotive Press Line
Installed in the main press ram drive connections on our automotive transfer press. The TS7Z75×120 handles the cyclic peak torque of the press drive reliably. After 24 months and over 2 million press cycles, we have not had a single locking assembly issue. The shaft surface condition after disassembly at our last scheduled maintenance was excellent.
— Applications Engineer, Ankara
★★★★☆
Spain — Hydraulic Press Manufacturing
Installed on hydraulic press main drive shaft connections. The TS7Z75×120 handles the peak torque of the pressing cycle without slip — the 91 kN axial capacity exceeds our press reaction force requirement. After 18 months of production we have not needed to re-tighten any of the locking assemblies.
— Senior Engineer, Bilbao
Frequently Asked Questions
What is the Ft (axial force) capacity of the TS7Z?
Ft is the maximum axial force the locking assembly can resist at the specified installation torque. In most applications, the combined torque and axial force loading must be checked against the rated values — if both torque and axial force act simultaneously, the effective capacity of each is reduced proportionally. Consult the interaction formula provided in the product documentation.
What is the maximum shaft diameter for the TS7Z series?
The TS7Z series covers shaft bore diameters from 15 mm (TS7Z15×45) to 110 mm (TS7Z110×160). If a shaft diameter outside this range is required, contact Ever Power to discuss alternative locking assembly series that may cover your requirement.
Is the TS7Z suitable for use in explosive atmospheres (ATEX)?
The TS7Z is a mechanical component and does not carry an ATEX electrical rating. The steel body has low spark risk from mechanical contact, and locking assemblies are commonly used in ATEX Zone 1 and Zone 2 machinery. Confirm the overall machine ATEX certification requirements with your safety engineer and Ex certification body.
What is the angular positioning accuracy of the TS7Z?
The TS7Z allows the hub to be positioned at any angular position relative to the shaft before tightening the clamping screws. Once tightened to M_a, the angular position is fixed. Repositioning requires loosening and retightening. For applications requiring angular adjustment, a position can be re-established to within the measurement resolution of your setup tooling.
Can the TS7Z be used with aluminium hubs?
Yes, provided the aluminium hub material has sufficient yield strength to withstand the Ps contact pressure from the outer ring. For common aluminium alloys (e.g. 6061-T6, yield ~275 MPa; 7075-T6, yield ~500 MPa), the Ps value for the selected TS7Z model must be below 0.9 × hub material yield strength.
Source the TS7Z75×120 Locking Assembly
Ever Power manufactures the TS7Z75×120 and the complete TS7Z locking assembly series — 31 bore sizes from 15 mm to 110 mm — direct from our factory. Provide your shaft diameter, hub bore, application torque, and quantity for a prompt technical review and factory-direct pricing.