Factory Direct | 42CrMo / 40Cr alloy steel | HRC48-52 hardness | HRC56-58 pins | Single (G) or double (GD) | Needle bearing (4000 RPM) or pin/block (1000 RPM) | H7 bore | 45° angle per joint | Keyway/hex/square hole options | OEM/ODM/OBM

The Apexcoupling G/GD series is a precision universal joint coupling engineered for reliable power transmission in demanding industrial applications. Manufactured from 42CrMo / 40Cr alloy steel with quenched and tempered treatment (HRC48-52, with pins up to HRC56-58), this coupling delivers exceptional strength, wear resistance, and durability. Available in single joint (G type) and double joint (GD type) configurations, the series features H7 precision bore and supports needle bearing for high-speed applications up to 4000 RPM, or pin/block (plain) bearing for low-speed, high-torque applications up to 1000 RPM. With 45° limit angle per joint and 304/316 stainless steel options, the G/GD series is the ideal solution for packaging machinery, woodworking equipment, multi-spindle drills, metallurgy, CNC machines, and general automation.

✅ Hardness up to HRC56-58 – high torque, high durability. Needle bearing (4000 RPM) or pin/block (1000 RPM). Single or double joint. H7 bore precision. Stainless steel option available. JB/T5901-1991 standard.

Key Technical Specifications

🔧 Custom bores, keyways, hexagon/square holes, materials (304/316 stainless steel), and special finishes available. Contact us with your specifications.

G (Single) vs GD (Double) – Which One Do You Need?

Rule of thumb:

• Use G type for straight-line applications with slight angular misalignment.

• Use GD type for applications where shafts are both angled and offset – common in conveyors, packaging machinery, and multi-spindle drills.

💡 Double joint configurations provide smoother power transmission and reduced vibration when both angular and parallel misalignment are present.

Bearing Selection – Pin/Block vs Needle Roller

The G/GD series offers two bearing options:

Recommendation:

• Choose pin/block (G/GD) for heavy-duty, low-speed applications with shock loads and high torque requirements.

• Choose needle bearing (GZ/GDZ) for high-speed applications (above 1000 RPM) where precision and low friction are priorities.

Material & Hardness – 42CrMo / 40Cr Alloy Steel

✅ The combination of 42CrMo alloy steel with quenched & tempered treatment provides the high strength, wear resistance, and durability required for demanding industrial applications.

Product Features & Advantages

Applications

• Packaging Machinery – Conveyors, wrapping machines, carton sealers

• Woodworking Machinery – Multi-spindle drills, routers, saws

• Multi-Spindle Drills – Precision drilling operations

• Metallurgical Equipment – Rolling mills, continuous casting lines

• CNC Machines – Feed drives, positioning systems

• Printing Equipment – Register control, high-speed operation

• Textile Machinery – Spinning, weaving equipment

• FA Automation – Pick-and-place systems, indexing tables

• Food & Beverage Processing – With 304/316 stainless steel option

• General Industrial Machinery – Pumps, mixers, conveyors

Why Choose Apex Coupling for G/GD Universal Joints?

FAQ

Q: What is the difference between G type and GD type?
A: G type is a single universal joint – for angular misalignment only. GD type is a double universal joint – allows both angular misalignment and parallel offset, providing smoother motion.

Q: What bearing options are available?
A: Pin/block (plain) bearing (G/GD) – up to 1000 RPM, higher torque capacity. Needle bearing (GZ/GDZ) – up to 4000 RPM, low friction, maintenance-free.

Q: What is the maximum operating angle?
A: Each joint can operate up to 45° limit angle. For continuous operation with built-in bearings, we recommend ≤30°.

Q: What is the hardness of the coupling?
A: The body is quenched & tempered to HRC48-52. The pins are hardened to HRC56-58 (bearing steel) for superior wear resistance.

Q: What materials are available?
A: Standard is 42CrMo / 40Cr / 40CrNi / 20CrMo / 20CrMnVB alloy steel. We also offer 304 and 316 stainless steel for corrosion-resistant applications.

Q: What is the bore tolerance?
A: Standard finished bore tolerance is H7 for precision shaft fit.

Q: What bore and connection types are available?
A: We offer keyway, hexagon hole, square hole, spline, plain bore, internal spline shaft hole, spline shaft, optical shaft + pin hole, optical shaft + keyway, square shaft, hexagonal shaft, and small flange connections.

Q: What is the torque capacity of needle bearing vs pin/block?
A: Needle bearing torque capacity is approximately 50% of pin/block rating for the same joint size.

Q: Can I get a custom coupling?
A: Yes. We offer OEM, ODM, and OBM support – custom bores, materials, finishes, and special designs available.

Q: What is the warranty?
A: 1 Year – quality assured.

Request a Quote

Send us your configuration (G single or GD double), bearing type, material preference, bore size, and application details. Our engineers will recommend the optimal model and provide a quotation within 24 hours.