Laminated Membrane Couplings

Laminated membrane coupling is a precision mechanical transmission device that connects shafts through flexible metal diaphragm components. As a widely used type of coupling in modern industry, it exhibits excellent adaptability under various harsh working conditions with its unique structural characteristics and outstanding performance. It is widely used in wind power generation, petrochemical industry, ship propulsion, compressor system and other fields, and has become one of the preferred solutions for high-precision and reliable transmission connection.

Core structure of membrane coupling

The core of a laminated membrane coupling lies in its intricate metal diaphragm assembly design, typically consisting of the following main components:

• Metal diaphragm group: composed of multiple high elasticity stainless steel thin sheets stacked together, with a thickness usually between 0.2-1.0mm. It is made into a corrugated or flat shape through a special forming process, which is a key component for transmitting torque and absorbing deviation.
  

• Wheel hub assembly: consists of two wheels installed on the drive shaft and the driven shaft respectively, usually made of high-strength alloy steel and precision machined to ensure installation accuracy.
  

• Intermediate shaft (some models): Used to connect the diaphragm groups at both ends in long-distance transmission, the length can be adjusted as needed.
  

• Connecting bolts: High strength fasteners that ensure reliable connections between components, typically designed with anti loosening features.

The unique advantages of laminated membrane couplings

Compared to traditional types such as gear couplings and elastic couplings, laminated membrane couplings have several significant advantages:

• Backless transmission: Direct contact between metals ensures zero backlash, especially suitable for situations requiring precise positioning
  

• Maintenance free design: No lubrication required, reducing maintenance costs and downtime
  

• High torsional stiffness: The metal diaphragm provides extremely high torsional stiffness, ensuring precise phase control
  

• Long service life: High quality stainless steel materials can be used for more than 10 years under normal working conditions
  

• Environmental adaptability: high temperature resistance, corrosion resistance, working temperature range can reach -50 ℃ to+300 ℃
  

• Lightweight: Compared to gear couplings with the same torque capacity, the weight can be reduced by 30-50%

Working principle of laminated membrane coupling

Laminated membrane couplings achieve multiple functions through the elastic deformation of metal diaphragms:

• Torque transmission: The driving torque is transmitted from one hub to another hub through the shear force of the diaphragm
  

• Deviation compensation:
  Axial deviation: absorbed through the tensile/compressive deformation of the diaphragm
  Radial deviation: compensated by the bending deformation of the diaphragm
  Angular deviation: adapted through the conical deformation of the membrane
  

• Vibration damping: The elastic properties of the diaphragm can effectively filter high-frequency vibrations
  

• Electrical insulation: Diaphragm made of non-conductive materials can provide electrical isolation between shafts

It is worth noting that the compensation capability of a single membrane is limited, and a multi-layer membrane stacking design is usually used to enhance the compensation capability without significantly reducing the torsional stiffness.

The main types of laminated membrane couplings

According to the structure and application requirements, laminated membrane couplings can be divided into several main types:

• Single membrane type:
  The simplest structure and lowest cost
  Limited compensation capability, mainly used in small deviation situations
  Typical applications: small pumps, compressors

• Double membrane type:
  Two sets of membranes are connected through an intermediate shaft
  Enhanced bias compensation capability
  Typical applications: Medium sized wind turbines, generator sets

• Multi membrane type:
  Three or more membrane combinations
  Maximum compensation capability, high torque density
  Typical applications: ship propulsion, large compressors

• Special structural type:
  Equipped with safety shear device: overload protection function
  Insulation type: Electrical isolation version
  Airtight type: used in vacuum or high-pressure environments

Selection Guide for laminated membrane couplings

The correct selection of laminated membrane couplings requires consideration of multiple key factors:

• Torque parameters:
  Rated torque: calculated based on driving power and speed
  Peak torque: considering starting and impact loads
  Safety factor: usually taken as 1.5-3.0

• Deviation requirements:
  Axial deviation: generally allowed 0.5-5mm
  Radial deviation: usually 0.2-3mm
  Angular deviation: commonly 0.5 ° -3 °

• Environmental factors:
  temperature range
  corrosive medium
  Explosion-proof requirements

• Dynamic characteristics:
  critical speed
  Torsional vibration frequency
  Unbalanced response

• Installation restrictions:
  spatial dimensions
  Axis end distance
  Dismantling requirements

Installation and maintenance of laminated membrane coupling

• Installation points:
  Ensure that the axis alignment accuracy is within the allowable range of the coupling
  Use specialized tools for installation and avoid knocking
  Tighten the bolts step by step according to the specified torque value
  Check the axial preload (if applicable)
  Perform static and low-speed dynamic balance checks

• Maintenance suggestion:
  Regularly check the tightening status of bolts
  Monitor whether the membrane has cracks or permanent deformation
  Check the alignment of the shaft, especially after foundation settlement
  Record vibration data and analyze trend changes
  Establish a preventive maintenance plan

Typical application areas of laminated membrane couplings

• Energy industry:
  Gas turbine generator set
  Wind power gearbox connection
  Main pump drive for nuclear power plant

• Petrochemical industry:
  Large compressor drive
  Pump set transmission system
  Offshore platform equipment

• Shipbuilding industry:
  Main propulsion system
  shaft generator
  Servo drive

• Industrial manufacturing:
  Rolling mill transmission
  Papermaking machinery
  precision machine tool

As an important component of modern mechanical transmission systems, membrane couplings will continue to drive industrial equipment towards higher efficiency, reliability, and intelligence through technological advancements. With the application of new materials and processes, the performance boundaries of membrane couplings will continue to expand in the future.