Crane coupling is a key component that connects two shafts or shafts with other rotating parts in the crane transmission system. It is mainly used to transmit torque, compensate for installation errors, and buffer impact vibration. The following is a detailed classification, selection points and maintenance recommendations for crane couplings:
1. Common types and featuresGear coupling
Features: strong load-bearing capacity, large radial and angular deviations are allowed, and impact resistance.
Application: Suitable for high-speed or low-speed shaft transmission of heavy cranes (such as bridge and gantry cranes).
Disadvantages: Regular lubrication is required, and maintenance requirements are high.
Elastic coupling (such as plum blossom type, tire type)
Features: Vibration is buffered by elastic elements (rubber, polyurethane) to compensate for minor deviations.
Application: Connection between light and medium-sized cranes or motors and reducers.
Advantages: Maintenance-free, easy to install, but low load-bearing capacity.
Universal coupling
Features: Can compensate for large angle deviations (usually 15°-45°).
Application: Used in situations where directional transmission is required, such as crane slewing mechanisms.
Chain coupling
Features: simple structure, low cost, and certain radial deviation is allowed.
Disadvantages: easy to generate noise after wear, and requires regular lubrication.
Rigid coupling
Features: no compensation ability, but extremely high centering accuracy requirements.
Application: used in strictly coaxial occasions (such as some metallurgical cranes).
2. Key factors for selectionTorque and speed
Calculate the maximum torque under actual working conditions (considering starting and braking impact), and select a coupling with a rated torque higher than the calculated value.
Deflection compensation requirements
Select the type according to the centering of the shaft:
Large radial/angular deviation → gear or universal coupling
Minor deviation → elastic coupling
Environmental conditions
Stainless steel or special coating couplings are required for high temperature and corrosive environments; select a type with good sealing when there is a lot of dust.
Installation space
Plum blossom couplings can be selected for compact spaces, and long universal couplings are required for large spans.
Maintenance convenience
Lubricated couplings (such as gear type) need to be refueled regularly, and elastic couplings are suitable for occasions that are difficult to maintain.
3. Maintenance and troubleshootingRegular inspection
Lubrication condition (gear couplings are filled with grease every 3-6 months).
Whether the elastic element is aging or cracked (the replacement cycle is usually 2-5 years).
Bolt tightness to prevent loosening.
Common faults
Abnormal vibration: may be caused by poor alignment or coupling wear.
Noise: Gear coupling lacks oil or elastic element is damaged.
Overheating: caused by overload or insufficient lubrication.
Replacement standard
Tooth surface wear exceeds 20% of tooth thickness or broken teeth appear.
Elastic element is permanently deformed or torn.
4. PrecautionsInstallation accuracy: Even if a compensable coupling is used, the shaft should be aligned as much as possible (such as laser alignment).
Safety factor: Cranes are frequently started and stopped, and the recommended torque safety factor is 1.5-2.
Brand selection: SEW, SIEMENS, domestic brands such as Tailong are preferred to ensure reliable materials and processes.
If more specific model recommendations are required, please provide the crane's tonnage, transmission form (such as QD bridge crane) or working condition details (such as high temperature, frequent start and stop).
