Description
TS7Z22×55 Locking Assembly – 22mm Shaft 55mm OD Keyless Rigid Shaft-Hub Connector
The TS7Z22×55 transitions into the mid-range of the TS7Z series, with a significant step up in axial force capacity (Ft = 25.2 kN) compared to the sub-22 mm models. The 22 mm bore suits IEC frame 100 and 112 motor shafts, and the higher M_a of 17 N·m versus smaller models provides a clamping force commensurate with the increased bore diameter. 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 — 103 MPa for the TS7Z22×55 at the specified M_a of 17 N·m — generates a friction connection that transmits both torque (Mt = 0.277 kN·m) and axial force (Ft = 25.2 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 | TS7Z22×55 |
| Type | Locking Assembly (Keyless Shaft-Hub Connection) |
| Shaft Bore (d) | 22 mm |
| Outer Diameter (D) | 55 mm |
| Rated Axial Force (Ft) | 25.2 kN |
| Rated Torque (Mt) | 0.277 kN·m |
| Surface Pressure (Ps) | 103 MPa |
| Installation Screw Torque (Ma) | 17 N·m |
| Mass (G) | 0.7 kg |
| Material | Steel |
| Standard | GB/T 5106 compatible |
Dimensional Reference
Structural Cross-Section
Installation and Design Guidance
Installation of the TS7Z22×55 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 = 17 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 (103 MPa) ≤ 0.9 × shaft yield strength. For C45 steel (yield ~370 MPa): 0.9 × 370 = 333 MPa > 103 MPa — acceptable. For aluminium alloy 6061-T6 (yield ~275 MPa): 0.9 × 275 = 247 MPa; compare with 103 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
★★★★★
Norway — Oil & Gas Field Equipment
We use the TS7Z22×55 for mud pump crankshaft to drive shaft connections at our drilling facility. The locking assembly’s keyless design eliminates the keyway stress riser from the crankshaft, which was a fatigue crack initiation concern at our previous scheduled inspection.
— Systems Engineer, Stavanger
★★★★★
Portugal — Railway Maintenance Equipment
Installed on wheel set drive connections on our track geometry measurement vehicles. The TS7Z22×55 provides a precisely reproducible connection that can be disassembled and reassembled to the same torque standard at each wheelset overhaul. The published preload torque of 17 N·m is the key parameter for our maintenance procedure.
— Design Engineer, Porto
★★★★☆
Czech Republic — Crane & Hoist OEM
The TS7Z22×55 is our standard for crane hoist drum shaft connections. The locking assembly design provides a safe, keyless connection that does not require any modification to the drum shaft or hub bore — both can be reused when the locking assembly is replaced at its maintenance interval.
— Project Engineer, Brno
Frequently Asked Questions
Are dimensional drawings available for all TS7Z models?
Yes. Dimensional drawings in PDF and DXF format are available for all 31 TS7Z models on request. Contact Ever Power with your model number for drawing provision. CAD models in STEP format can also be provided for most sizes.
What is the operating principle of a locking assembly?
A locking assembly — also called a keyless shaft-hub connection or friction locking device — uses axial bolt preload to expand a split inner ring against the shaft surface and simultaneously contract a tapered outer ring against the hub bore. This generates a uniform radial clamping pressure that transmits torque through friction, eliminating the need for a keyway or interference fit.
Can a locking assembly be reused after disassembly?
Yes. TS7Z locking assemblies can be disassembled and reused, provided the shaft and hub bore surfaces are inspected and show no scoring, corrosion, or fretting damage. Clean and lubricate the tapered contact surfaces before reassembly and retighten to the specified M_a torque.
What shaft surface finish is recommended for the TS7Z?
A shaft surface finish of Ra 0.8 to 1.6 μm (Rz 6.3 to 10 μm) and a tolerance of h6 or k6 are recommended. Coarser surface finishes reduce the effective friction area; finer finishes may reduce friction coefficient. The shaft surface must be clean and dry at installation — do not use lubricant on the shaft surface within the clamping zone.
Is the TS7Z suitable for reversing torque applications?
Yes. The locking assembly transmits torque equally in both rotational directions through friction — direction of rotation does not affect the connection. For applications with torque reversal, the safety factor on the rated torque should account for any dynamic amplification of the reversal shock.
Source the TS7Z22×55 Locking Assembly
Ever Power manufactures the TS7Z22×55 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.