Description
GT5 GT Type Sleeve Coupling – 45–63mm Bore Rigid Muff Coupling for Zero-Backlash Shaft Connection
The GT5 GT type sleeve coupling — also known as a muff coupling — is the simplest and most direct form of rigid shaft coupling: a single cylindrical steel body with a through bore machined to receive two co-linear shaft ends, transmitting torque through keyway and fitted key engagement on each shaft side. At 120 mm outer diameter and 242 mm overall length, the GT5 provides a compact, maintenance-free rigid connection for 45–63 mm shaft diameters, rated at 1000 N·m nominal torque at up to 4500 rpm maximum speed. The GT5 covers the 45–63 mm bore range common in IEC frame 160 and 200 motors. At 1,000 N·m rated torque and 4,500 rpm, it serves compressor, fan, and large pump drive connections where a compact one-piece rigid coupling is preferred over a flanged arrangement.
The operating principle of the GT sleeve coupling is direct and reliable. Each shaft end is inserted into one half of the sleeve bore. A fitted key is placed in the matching keyways of both the shaft and the sleeve bore on each side — two keys total, typically positioned 180° apart. When the coupling rotates, torque is transmitted from the driving shaft to the sleeve through key-keyway bearing contact, and from the sleeve to the driven shaft through the same mechanism on the opposite side. There are no flexible elements, no preloaded fasteners to maintain, and no wear surfaces subject to degradation under normal operating conditions. The result is a permanent, zero-backlash connection that requires essentially no maintenance throughout its service life, provided the connected shafts remain accurately aligned.
The H7 bore tolerance and GB3852-1997 keyway standard ensure dimensional compatibility with standard motor and driven equipment shaft ends throughout the GT series. For special shaft configurations — non-standard diameters, tapered bores, or hydraulic fit bores — custom machining is available. The complete GT series, from GT1 through GT10, is listed on our product catalog page.
Technical Specifications
| Parameter | Value |
|---|---|
| Model | GT5 |
| Type | GT Type Sleeve Coupling (Muff Coupling) |
| Bore Range (d) | 45–63 mm |
| Outer Diameter (D) | 120 mm |
| Overall Length (L) | 242 mm |
| Nominal Torque (Tn) | 1000 N·m |
| Maximum Speed [n] | 4500 rpm |
| Bore Tolerance | H7 standard |
| Keyway Standard | GB3852-1997 |
| Mass | 14.5 kg |
Dimension Reference

Construction and Functional Features

The GT5 body is machined from high-quality cast iron or cast steel — material selection dependent on model size and rated torque. The bore is machined to H7 tolerance to provide a controlled fit against the shaft end, complementing the key-keyway torque transmission with a stable radial contact between shaft and bore. The outer diameter is machined concentric with the bore to ensure rotational balance. Keyway slots are machined to GB3852-1997 standard dimensions for the specified bore size — verifying compatibility with standard motor shaft keyways without modification.
Zero Backlash
Rigid key-keyway torque transmission with no play or compliance — every angular increment on the driving shaft is replicated exactly on the driven shaft. Essential for phase-critical and encoder feedback applications.
Maintenance-Free Service Life
No wear elements, no elastomeric components to degrade, no bolts to retorque. Once correctly installed on aligned shafts, the GT sleeve coupling requires no maintenance throughout its service life.
Compact One-Piece Design
Single cylindrical body — no bolted flanges, no split halves, no external fasteners. Lowest-profile rigid coupling available for co-linear shaft connections, minimising guard size and axial space requirements.
Standard Keyway Compatibility
Bore and keyway dimensions to GB3852-1997 and H7 bore tolerance ensure direct compatibility with standard motor and driven equipment shaft ends throughout the industrial motor range.
Manufacturing Quality

Typical Applications
- Precision instrument and automation drives — where zero backlash and angular fidelity between shafts are required
- High-speed motor to driven shaft connections — up to the model’s maximum speed rating with minimal added inertia
- Printing and packaging machine drives — phase-critical connections where indexing accuracy is essential
- Pump direct drive connections — close-coupled motor-to-pump rigid shaft coupling
For technical enquiries and volume supply information, visit our contact page.
Customer Reviews and Case Studies
★★★★★
Sweden — Industrial Compressor OEM
The GT5 sleeve coupling is our standard for connecting motor to compressor crankshaft on our reciprocating air compressor range. At 1,000 N·m, it handles our compressor drive torque with a 1.8× safety factor and the 4,500 rpm rating covers our direct-drive configurations.
— Senior Engineer, Gothenburg
★★★★★
Turkey — Cement Plant
Installed on raw mill auxiliary drive shaft connections. The GT5 rigid sleeve coupling has operated continuously for 28 months in the high-dust environment of our cement plant without any coupling maintenance requirements.
— Maintenance Supervisor, Ankara
★★★★☆
South Africa — Mining Processing Plant
Used on flotation cell drive shaft connections at our platinum mine. The solid steel body withstands the vibration environment of our processing plant and the 45–63 mm bore range matched our motor and gearbox output shaft sizes directly.
— Mechanical Foreman, Rustenburg
Frequently Asked Questions
What torque standards does the GT sleeve coupling conform to?
GT type sleeve couplings conform to Chinese national standards for rigid sleeve couplings. The keyway and bore dimensions comply with GB3852-1997. Dimensional and performance parameters comply with the relevant GB standard for sleeve coupling series.
Is the GT sleeve coupling suitable for reversing duty?
Yes. The key-keyway torque transmission mechanism is effective in both rotational directions. For frequent high-speed reversals, the key side face contact stress should be checked against the allowable bearing stress of the key and keyway materials, as reversals impose alternating contact loads on opposite key faces.
What is the dimensional relationship between bore and outer diameter in the GT series?
The wall section (OD minus bore) is sized to provide adequate structural integrity at the rated torque for each model. For the larger bore sizes within each model’s range, the wall section is thinner — this is why maximum bore sizes within a model must not be exceeded. For bores near the model maximum, verify wall section adequacy if keyway machining is also required.
Can GT sleeve couplings be supplied with metric or imperial bore sizes?
Standard bores are metric. Imperial bore sizes within the model’s overall bore range can be machined on request. Specify the required bore diameter and tolerance class when placing your order.
What documentation is available for the GT sleeve coupling for compliance purposes?
Material certificates, dimensional inspection reports, and hydrostatic test certificates (where applicable) are available on request. For regulated industries (pharmaceutical, food, petrochemical), specify documentation requirements when submitting your enquiry.
Source the GT5 GT Sleeve Coupling
Ever Power manufactures the GT5 and the complete GT sleeve coupling series — GT1 through GT10, covering 12 mm to 200 mm bore — direct from our factory. Specify bore diameters, keyway requirements, and any non-standard dimensions for a prompt technical and commercial response.
