{"id":3499,"date":"2026-07-08T05:16:20","date_gmt":"2026-07-08T05:16:20","guid":{"rendered":"https:\/\/rigid-shaft-coupling.top\/product\/ts7z42x78-locking-assembly-rigid-coupling-42mm-shaft-78mm-od-keyless-hub-connection\/"},"modified":"2026-07-08T05:16:21","modified_gmt":"2026-07-08T05:16:21","slug":"ts7z42x78-locking-assembly-rigid-coupling-42mm-shaft-78mm-od-keyless-hub-connection","status":"publish","type":"product","link":"https:\/\/rigid-shaft-coupling.top\/pl\/product\/ts7z42x78-locking-assembly-rigid-coupling-42mm-shaft-78mm-od-keyless-hub-connection\/","title":{"rendered":"TS7Z42\u00d778 Locking Assembly Rigid Coupling \u2013 42mm Shaft 78mm OD Keyless Hub Connection"},"content":{"rendered":"
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TS7Z42\u00d778 Locking Assembly \u2013 42mm Shaft 78mm OD Keyless Rigid Shaft-Hub Connector<\/h1>\n

The TS7Z42\u00d778<\/strong> covers the 42 mm shaft size found in certain European standard motors and heavy-duty gearbox output shafts. The slight OD increase to 78 mm provides additional ring wall section compared to the 75 mm OD models at a closely adjacent bore size, supporting the 64 MPa surface pressure rating with an adequate safety margin in standard steel shaft materials. For a complete listing of all TS7Z locking assembly models, visit our product catalog<\/a>.<\/p>\n

The TS7Z locking assembly operates on the principle of tapered ring compression: two tapered steel rings \u2014 inner and outer \u2014 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 \u2014 64 MPa for the TS7Z42\u00d778 at the specified M_a of 42 N\u00b7m \u2014 generates a friction connection that transmits both torque (Mt = 0.624 kN\u00b7m) and axial force (Ft = 31.2 kN) without any mechanical interlock element. No keyway is required in either the shaft or the hub bore.<\/p>\n

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 \u2014 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 \u2014 mills, fans, compressors, and crushers \u2014 this durability improvement is a primary selection rationale.<\/p>\n

Technical Specifications<\/h2>\n
\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Parameter<\/th>\nValue<\/th>\n<\/tr>\n<\/thead>\n
Model<\/td>\nTS7Z42\u00d778<\/td>\n<\/tr>\n
Type<\/td>\nLocking Assembly (Keyless Shaft-Hub Connection)<\/td>\n<\/tr>\n
Shaft Bore (d)<\/td>\n42 mm<\/td>\n<\/tr>\n
Outer Diameter (D)<\/td>\n78 mm<\/td>\n<\/tr>\n
Rated Axial Force (Ft)<\/td>\n31.2 kN<\/td>\n<\/tr>\n
Rated Torque (Mt)<\/td>\n0.624 kN\u00b7m<\/td>\n<\/tr>\n
Surface Pressure (Ps)<\/td>\n64 MPa<\/td>\n<\/tr>\n
Installation Screw Torque (Ma)<\/td>\n42 N\u00b7m<\/td>\n<\/tr>\n
Mass (G)<\/td>\n1.33 kg<\/td>\n<\/tr>\n
Material<\/td>\nSteel<\/td>\n<\/tr>\n
Standard<\/td>\nGB\/T 5106 compatible<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

Dimensional Reference<\/h2>\n

\"TS7Z42\u00d778<\/p>\n

Structural Cross-Section<\/h2>\n

\"TS7Z42\u00d778<\/p>\n

Installation and Design Guidance<\/h2>\n

\"TS7Z42\u00d778<\/p>\n

Installation of the TS7Z42\u00d778 requires the shaft surface to be clean, dry, and within an h6 or k6 shaft tolerance, with a surface finish of Ra 0.8\u20131.6 \u03bcm. The hub bore should be machined to H7 tolerance. Clamping screw threads and head bearing faces must be lubricated with MoS\u2082 paste before installation to ensure the M_a = 42 N\u00b7m tightening torque produces the correct clamping force. Tighten all screws in a star pattern in at least three progressive passes \u2014 do not fully tighten one screw before the others.<\/p>\n

To verify shaft material suitability, check: Ps (64 MPa) \u2264 0.9 \u00d7 shaft yield strength. For C45 steel (yield ~370 MPa): 0.9 \u00d7 370 = 333 MPa > 64 MPa \u2014 acceptable. For aluminium alloy 6061-T6 (yield ~275 MPa): 0.9 \u00d7 275 = 247 MPa; compare with 64 MPa for this model. If the shaft material yield strength is insufficient, contact our contact our team<\/a> for a re-rated configuration.<\/p>\n

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Keyless Design<\/h3>\n

No keyway in shaft or hub. Eliminates keyway stress concentration and fretting wear. Angular position can be set freely \u2014 no keyway angular constraint.<\/p>\n<\/div>\n

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Self-Releasing Disassembly<\/h3>\n

Back off clamping screws in a star pattern \u2014 the taper geometry produces a self-releasing action requiring no extraction tools or heat. Shaft and hub surfaces are undamaged after removal.<\/p>\n<\/div>\n

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Uniform Load Distribution<\/h3>\n

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.<\/p>\n<\/div>\n

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Bidirectional Torque<\/h3>\n

Frictional connection transmits equal torque in both rotational directions. No directional constraint \u2014 suitable for reversing drive applications without additional design consideration.<\/p>\n<\/div>\n<\/div>\n

Customer Reviews and Case Studies<\/h2>\n
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\u2605\u2605\u2605\u2605\u2605<\/p>\n

Italy \u2014 Agricultural Machinery OEM<\/p>\n

Used in combine harvester threshing drum drive connections. The TS7Z42\u00d778’s installation procedure via a calibrated torque wrench is straightforward for our field service teams and the locking assembly releases cleanly during drum overhaul without requiring specialised extraction equipment.<\/p>\n

\u2014 Mechanical Engineer, Turin<\/p>\n<\/div>\n

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\u2605\u2605\u2605\u2605\u2605<\/p>\n

France \u2014 Food & Beverage Processing<\/p>\n

Installed on conveyor drive shaft connections in our bottling plant. The TS7Z42\u00d778 allowed installation by our maintenance team using only standard torque tools. The published surface pressure of 64 MPa was used to verify shaft suitability in our design review, which is not possible with conventional keyed connections.<\/p>\n

\u2014 Applications Engineer, Lyon<\/p>\n<\/div>\n

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\u2605\u2605\u2605\u2605\u2606<\/p>\n

Finland \u2014 Wood Processing Equipment<\/p>\n

The TS7Z42\u00d778 is installed on chipper disc drive shaft connections at our wood processing facility. The locking assembly handles the high-energy shock loads from disc chipping operations without slip. The 1.33 kg mass is manageable by our two-person maintenance team without lifting equipment.<\/p>\n

\u2014 Senior Engineer, Tampere<\/p>\n<\/div>\n<\/div>\n

Frequently Asked Questions<\/h2>\n