Brief Introduction of H-Type Elastic Coupling

The H-type elastic block coupling is a very common type of coupling and belongs to the category of elastic couplings. It uses polyurethane elastic blocks as intermediate connecting and damping elements to connect two shafts while compensating for a certain amount of misalignment.

Due to its simple structure and ease of maintenance, the H-type elastic coupling is one of the most widely used classic couplings in industrial applications.

The following is a detailed introduction to its features, structure, applications, and selection considerations.

The H-type elastic block coupling mainly consists of two hubs and elastic blocks.
The hubs are usually made of steel. Each hub is equipped with a flange, and several pin holes are evenly distributed along the circumference.

H-Type Elastic Block: This is the core component of the coupling. It is made of polyurethane material, offering excellent elasticity and wear resistance.

Connection Method: The H-type elastic block is inserted into the pin holes of one hub. Then, the pin holes of the other hub are aligned with the elastic blocks. After assembly, the two hubs are clamped and fixed together to complete the coupling installation.

Working Principle and Performance Characteristics

Torque Transmission:
Torque is transmitted by compressing the elastic blocks. The elastic blocks are subjected to shear and compressive forces within the pin holes, enabling flexible transmission of power.

Misalignment Compensation:

Radial, Angular, and Axial Misalignment:
The coupling can compensate for small installation errors, typically: Radial misalignment ≤ 0.15–0.25 mm, Angular misalignment ≤ 0°30′.

Elastic Damping:
The elasticity of the elastic blocks absorbs shock and vibration during start-up, shutdown, or load fluctuations, thereby protecting the motor and equipment bearings.

Electrical Insulation:
The polyurethane material provides electrical insulation, which helps prevent stray currents to a certain extent.

Easy Maintenance:
After wear, only the H-type elastic blocks usually need to be replaced, without replacing the entire coupling, lower maintenance costs.

Main Advantages

a. Simple structure and easy manufacturing.
b. Maintenance-free, no lubrication required.
c. Easy disassembly and quick replacement of elastic elements.
d. Cost-effective.
e. Provides vibration damping and electrical insulation to a certain extent.

Typical Applications

Due to its economical and practical design, the H-type elastic block coupling is widely used in transmission systems with medium and small power, low to medium speed, and non-severe operating conditions, such as: Fans, Water pumps, Belt conveyors, Hoists, Agricultural machinery, Textile machinery, Auxiliary drives of general machine tools.

Selection Guidelines (Key Points)

Rated Torque: The rated torque Tn of the selected coupling must be greater than the calculated actual torque Tc.

Tc = operating condition factor K * theoretical torque T. The operating condition factor K is selected based on the type of load (uniform, moderate impact, heavy impact), and is usually 1.5 to 3.0.

Shaft bore and Keyway: Determine the shaft diameters d1 and d2 at both ends, as well as the bore type (usually cylindrical bore, type Y, or tapered bore, type J) and the keyway dimensions (according to GB/T 3852).

Speed: The allowable speed of the H-type elastic block coupling must be higher than the actual operating speed.

Misalignment Compensation Requirement: Evaluate whether the possible installation misalignment is within the allowable range of the coupling.

Operation and Maintenance Recommendations

Proper Alignment: Although the coupling has misalignment compensation capability, proper alignment should still be ensured during installation to extend the service life of the elastic blocks.

Regular Inspection: During operation, pay attention to any abnormal noise or vibration. Periodically shut down the equipment to check the wear condition of the elastic blocks. If there is obvious crushing, cracking, or excessive clearance, the elastic blocks should be replaced in time.

Avoid Excessive Misalignment: Long-term operation under excessive misalignment conditions will significantly shorten the service life of the elastic blocks.

Spare Parts Stock: It is recommended to keep several sets of elastic blocks of the same specification as wearing spare parts.

The H-type elastic block coupling is a general-purpose coupling featuring the core advantages of simplicity, cost-effectiveness, and practicality.
With proper selection and correct installation, it can provide reliable service in a wide range of conventional power transmission applications.

For more information and technical consultation, please contact Kudosworld.