Description
TS7Z19×50 Locking Assembly – 19mm Shaft 50mm OD Keyless Rigid Shaft-Hub Connector
The TS7Z19×50 serves the 19 mm shaft size found in some imperial-frame motor outputs and specialised gearbox shaft ends. Its 0.159 kN·m torque rating and 16.8 kN axial capacity cover standard duty conveyor and fan drives at this shaft size, and the shared 50 mm OD with the TS7Z18×50 allows a common hub outer bore to be used for both sizes. 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 — 100 MPa for the TS7Z19×50 at the specified M_a of 17 N·m — generates a friction connection that transmits both torque (Mt = 0.159 kN·m) and axial force (Ft = 16.8 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 | TS7Z19×50 |
| Type | Locking Assembly (Keyless Shaft-Hub Connection) |
| Shaft Bore (d) | 19 mm |
| Outer Diameter (D) | 50 mm |
| Rated Axial Force (Ft) | 16.8 kN |
| Rated Torque (Mt) | 0.159 kN·m |
| Surface Pressure (Ps) | 100 MPa |
| Installation Screw Torque (Ma) | 17 N·m |
| Mass (G) | 0.5 kg |
| Material | Steel |
| Standard | GB/T 5106 compatible |
Dimensional Reference
Structural Cross-Section
Installation and Design Guidance
Installation of the TS7Z19×50 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 (100 MPa) ≤ 0.9 × shaft yield strength. For C45 steel (yield ~370 MPa): 0.9 × 370 = 333 MPa > 100 MPa — acceptable. For aluminium alloy 6061-T6 (yield ~275 MPa): 0.9 × 275 = 247 MPa; compare with 100 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
★★★★★
Spain — Hydraulic Press Manufacturing
Installed on hydraulic press main drive shaft connections. The TS7Z19×50 handles the peak torque of the pressing cycle without slip — the 16.8 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
★★★★★
Sweden — Rubber Processing Equipment
We use the TS7Z19×50 for open mill roll drive connections. The locking assembly’s keyless design allows roll changes without machining a new keyway each time a replacement roll is fitted — a significant time saving in our maintenance workflow.
— Project Manager, Gothenburg
★★★★☆
France — Food & Beverage Processing
Installed on conveyor drive shaft connections in our bottling plant. The TS7Z19×50 allowed installation by our maintenance team using only standard torque tools. The published surface pressure of 100 MPa was used to verify shaft suitability in our design review, which is not possible with conventional keyed connections.
— Applications Engineer, Lyon
Frequently Asked Questions
What clamping screw type is used in the TS7Z?
The TS7Z uses socket head cap screws (hexagon socket, DIN 912 equivalent) of appropriate size for each frame. A hex key of the correct size must be used for installation and removal. The screw size varies by TS7Z model — refer to the product drawing or contact Ever Power for the specific screw specification for your model.
How does shaft diameter affect the rated torque of a locking assembly?
Rated torque Mt scales approximately with the cube of shaft diameter for a given surface pressure. This is why the TS7Z series shows a large increase in Mt from smaller models (0.126 kN·m for TS7Z15×45) to larger ones (7.20 kN·m for TS7Z110×160) — the shaft diameter increase drives a disproportionate increase in torque capacity at a similar or lower surface pressure.
Can the TS7Z be used with hollow shafts?
Yes, provided the hollow shaft wall thickness is sufficient to withstand the Ps radial contact pressure without collapse. For hollow shaft applications, calculate the wall stress using the thick-walled cylinder formula with the inner pressure equal to Ps and the relevant wall geometry. Contact Ever Power if you require assistance with the hollow shaft calculation.
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.
What is the difference between the TS7Z inner ring and outer ring?
The inner ring contacts the shaft bore directly and expands radially outward when the clamping screws are tightened. The outer ring contacts the hub bore and contracts radially inward. The tapered interface between the two rings converts axial screw preload into radial clamping force on both surfaces simultaneously.
Source the TS7Z19×50 Locking Assembly
Ever Power manufactures the TS7Z19×50 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.