Telescopic Universal Joint Coupling

Telescopic Universal Joint Couplings come in various structural forms, such as cross-shaft type, ball cage type, ball fork type, convex block type, ball pin type, ball hinge type, ball hinge plunger type, three-pin type, three-prong rod type, three-ball pin type, hinge rod type, etc. The most commonly used type is the cross-shaft type, followed by the ball cage type. A common feature of universal joint couplings is their large angular compensation capacity, and the included angle β between the two shaft axes varies with different structural types, generally ranging from β ≤ 5° to 45°.

From the kinematic analysis, the relationship between the angular velocity ω₁ of the driving end and the angular velocity ω₂ of the driven end of a universal joint coupling is divided into two categories: constant velocity and non-constant velocity.

Constant velocity universal joint couplings: Where ω₁ = ω₂, the driving and driven ends can rotate synchronously. Examples include double cross-shaft universal joint couplings, ball cage universal joint couplings, three-prong rod universal joint couplings, etc.

Non-constant velocity universal joint couplings: Where ω₁ ≠ ω₂, the driving and driven ends cannot rotate synchronously. An example is the single cross-shaft universal joint coupling.

By virtue of its structural characteristics, a Telescopic Universal Joint Coupling enables continuous rotation of the two connected shafts even when they are not on the same axis and have an included angle β, while reliably transmitting torque and motion. The most prominent features of universal joint couplings are their large angular compensation capacity, compact structure, and high transmission efficiency. In practical applications, they are classified into heavy-duty, medium-duty, light-duty, and small-sized types according to the magnitude of the transmitted torque. Heavy-duty universal joint couplings are commonly used in metallurgical machinery, heavy machinery, petroleum machinery, construction machinery, hoisting and transportation machinery, etc.; medium and light-duty universal joint couplings are used in vehicles such as automobiles and locomotives, as well as light industrial machinery; small-sized universal joint couplings mainly transmit motion and are generally used in precision machinery and control mechanisms.

Cross-Shaft Universal Joint Couplings

Cross-shaft universal joint couplings are among the most widely used universal joint couplings, with bearings being the wearing parts. The main differences between several large-scale cross-shaft universal joint couplings lie in variations of the bearing housing and cross yoke, forming different structural types. To ensure synchronization between the driving and driven ends, double-joint configurations are universally adopted in practical applications. The connection method for the double joint is either welding or bolted flange connection, with various intermediate length options available. The main types of cross-shaft Telescopic Universal Joint Coupling components are as follows:

SWC type integral yoke cross-shaft universal joint coupling (JB/T5513-2006)

SWP type split bearing housing cross-shaft universal joint coupling (JB/T3241-2005)

SWZ type integral bearing housing cross-shaft universal joint coupling (JB/T3242-1993)

WS type small double cross-shaft universal joint coupling (JB/T5901-1991)

WSD type small single cross-shaft universal joint coupling (JB/T5901-1991)

Cross assembly for SWP type cross-shaft universal joint couplings (JB/T7341.1-2005)

Cross assembly for WSC type cross-shaft universal joint couplings (JB/T7341.2-2006)

The above heavy-duty and small-sized cross-shaft universal joint couplings are general-purpose types. In the automotive industry, different vehicle models have their own dedicated cross-shaft universal joint couplings or other types of universal joint couplings. For example, passenger cars use ball cage universal joint couplings. In addition, agricultural machinery, construction machinery and other mobile machinery products also have dedicated universal joint couplings, most of which adopt cross-shaft universal joint couplings. This manual mainly introduces general-purpose cross-shaft universal joint couplings for heavy machinery and small cross-shaft universal joint couplings.

1.SWC Type Integral Yoke Cross-Shaft Universal Joint Coupling

The SWC type universal joint coupling features a bolt-free structure, with bearings fixed without bolts. This eliminates the weak link of failure due to bolt shearing, extends service life and facilitates maintenance. It is suitable for steel rolling machinery, hoisting and transporting machinery and other heavy machinery, used to connect drive shaft systems with different axes. It has a swing diameter of 100~1320 mm, transmits a nominal torque of 2.5~12000 kN·m, and allows a shaft deflection angle of 15°~25°.

2.Tags Example

1) turning diameter D=315 mm,length L=2500 mm the BH

Standard telescopic welded universal coupling:

SWC315BHx2500 coupling JB/T5513-2006

2) turning diameter D-440mm,length

L=3200mm of the WF-

based non-retractable flange universal coupling:

SWC440 WF x 3200 coupling JB/T5513-2006

3) turning diameter D =350 mm of WD-based non-stretch short

universal coupling:SWC350WD coupling JB/T5513-2006

Note: 1. Tf-in alternating load fatigue strength allowed by the torque.

2. Lmin-shortened the minimum length.

3. L-install length, determined by need.

Note: 1. Tf-in alternating load fatigue strength allowed by the torque.

2. Lmin-shortened the minimum length.

3. L-install length, determined by need.

Note: 1. Tf - in alternating load fatigue strength allowed by the torque.

2. Lmin - shortened the minimum length.

3. L - install length, determined by need.

Note: 1. Tf - in alternating load fatigue strength allowed by the torque.

2. Lmin - shortened the minimum length.

3. L - install length, determined by need.

Note: 1. Tf - in alternating load fatigue strength allowed by the torque.

2. Lmin - shortened the minimum length.

3. L - install length, determined by need.

Note: 1. Tf - in alternating load fatigue strength allowed by the torque.

2. Lmin - shortened the minimum length.

3. L - install length, determined by need.

Note: 1. Tf - in alternating load fatigue strength allowed by the torque.

2. Lmin - shortened the minimum length.

3. L - install length, determined by need.

Note: 1. Tf - in alternating load fatigue strength allowed by the torque.

2. Lmin - shortened the minimum length.

3. L - install length, determined by need.

Note: 1. Tf - in alternating load fatigue strength allowed by the torque.

1.L - install length, determined by need.

Connection of SWC type universal coupling with mating components

The Telescopic Universal Joint Coupling connects the flanges at both ends to other mating components via high-strength bolts and nuts. The connection dimensions of the mating components and the bolt pre-tightening torque shall comply with the provisions of Figure 4-53 and Table 4-53. The connecting bolts shall only be installed from the flange side of the mating components, and the nuts shall be pre-tightened from the opposite side. The mechanical properties of the bolts shall conform to the requirements for Grade 10.9 specified in GB/T 3098.1-2000, and the mechanical properties of the nuts shall conform to the requirements for Grade 10 specified in GB/T 3098.2-2000.

Note: 1. Tf - in alternating load fatigue strength allowed by the torque.

1.L - install length, determined by need.