Steel laminae couplings / laminae couplings
Torsionally stiff, backlash-free all-steel couplings offsetting misalignment and transmitting highest torques up to 280,000 Nm as a standard.
KTR steel laminae couplings transmit high torques up to 280.000 Nm with absolutely no backlash and torsional stiffness. The all-steel laminae sets with an optimised lamina contour made of high-strength, stainless spring steel ensure an increased fatigue life, higher permissible displacement capacities for axial, radial and angular shaft displacement as well as reduced reaction forces on the coupled shafts.
With the RADEX®-N and RIGIFLEX®-N series, KTR covers a wide range of applications, from standard drives to API-compliant process pumps and compressors.
- Torque: up to 280,000 Nm
- Displacement compensation: axial, radial and angular compensation
- Maintenance: maintenance-free and wear-free
- Temperature range: −30 °C to +280 °C
- Special versions: customized solutions for torques in the millions of Nm are possible
RADEX®-N steel laminae couplings
All-steel coupling for universal use in mechanical and plant engineering Suitable for nominal torques up to 280,000 Nm. Available in more than 8 types: NN, NENE, NNZ, NNW, NANA 3 (API 610), NANA 4, Composite and WEA.
RIGIFLEX®-N steel laminae couplings
Steel laminae couplings acc. to API 610/671 for pumps, compressors and turbines. Large shaft distances, high nominal torques.
Functioning and structure
Operating principle of the steel laminae coupling
Steel laminae couplings (also referred to as: all-steel couplings, laminae set couplings) usually consist of two hubs, two flexible laminae sets and a spacer. Torque is transmitted by both positive and friction fit via dowel pins that connect the laminae set reciprocally with the hubs - with absolutely no backlash and torsional stiffness. The elastic deformation of the steel laminas allow to offset axial, radial and angular shaft displacements at the same time.
Single-cardanic vs. double-cardanic
Single-cardanic (e. g. RADEX®-N NN): One laminae set and two hubs.
Offsets angular and axial displacement.
Double-cardanic (e. g. RADEX®-N NANA): Two hubs, two laminae sets and a spacer.Offsets angular, axial and radial displacement.
Frequent questions about steel laminae couplings
What is a steel laminae coupling and how does it work?
A steel laminae coupling is a torsionally stiff, backlash-free all-steel shaft coupling. It transmits torques via spring steel laminae sets that are reciprocally screwed with the hubs. It compensates for shaft displacement through flexible deformation of the laminas.
Which shaft displacements does a steel laminae coupling compensate for?
Three types: axial displacement (longitudinal displacement), radial displacement (parallel displacement) and angular displacement (inclination). Single-cardanic types compensate for angular displacement and axial displacement; double-cardanic ones additionally for radial displacement. Permissible values are depending on size - for details refer to configurator or data sheet.
Why using a steel laminae coupling instead of a gear coupling?
Maintenance-free (no lubrication), backlash-free (higher positioning accuracy), no wear, lower restoring forces, wider temperature range (−30 to +280°C). Gear couplings (e. g. GEARex®) remain favourable with extremely high torques >280,000 Nm.
Up to what temperature can steel laminae couplings be used?
Standard type: −30°C to +280°C (stainless steel laminas). RADEX®-N Composite with CFRP spacer: −40°C to +120°C. No limitation through lubricants or elastomers.
What does API 610 and API 671 mean for couplings?
API 610 is a standard for pump drives including the coupling.API 671 is a standard for the coupling itself, specifically with sophisticated drives in process and chemical industries.
How do I select the suitable steel laminae coupling?
Three key criteria: 1) torque, 2) maximum speed, 3) expected shaft misalignment. Select a series using the comparison table, specify the size in the KTR configurator, generate CAD data. As an alternative: fill in selection questionnaire.
Are KTR steel laminae couplings certified in accordance with ATEX?
Yes. RADEX®-N and RIGIFLEX®-N are certified in accordance with ATEX directive 2014/34/EU for potentially explosive areas. Type examination certification available for download.