- Automation & ControlView all 1,840 products
- AC Drives
- PLC & I/O Cards
- Industrial Communications
- Vibration Monitoring
- Automation Accessories
- Controllers & Data Acquisition
- Isolator & Barrier
- CCTV & Security
- Safety Switches & Guard Locking
- Encoders
- HMI Displays
- Industrial Computers
- Servo Drives
- Motor Soft Starters
- Pneumatic Cylinders
- Machine Vision
- Automation Software
- Robotics
Brand: KTR
KTR MONOLASTIC Flexible Flange Coupling
Description
One-piece flexible flange coupling for hydraulic pump drives
The KTR MONOLASTIC is a torsionally flexible flange coupling in one piece, designed to be plugged in axially. It is used between an engine or motor flywheel and a hydraulic pump, for example in mobile machinery and in diesel-driven pump sets. The elastomer part is bolted to the flywheel, and the hub on the pump shaft slides into it through a greased spline bore. This damps torsional vibration and compensates axial, radial and angular displacement of the connected shafts. The design is protected by patents EP 0 853 203 and US 6,117,017.
The values below come from KTR operating and assembly instructions KTR-N 48510 EN (edition 1) for MONOLASTIC types with 3 holes and SAE flanges.
Technical specifications
| Parameter | Specification |
|---|---|
| Manufacturer | KTR Systems GmbH, Rheine, Germany |
| Coupling type | One-piece torsionally flexible flange coupling, axially pluggable |
| Versions | Type with 3 holes; type SAE for flywheels to SAE J620 |
| Elastomer hardness | T65 and T70 (Shore A); G50 size uses T70 |
| 3-hole type, sizes | 22, 28, 32, 50-140, 50-165, 50-170 and 60-165 |
| 3-hole type, rated torque TKN | 40 Nm (size 22, T65) up to 400 Nm (size 60-165, T70) |
| 3-hole type, maximum torque TK max. | 100 Nm up to 1,000 Nm |
| SAE type, sizes | 30, 50, G50, 65 and 75 |
| SAE type, rated torque TKN | 200 Nm (size 30, T65) up to 1,850 Nm (size 75, T70) |
| SAE type, maximum torque TK max. | 400 Nm up to 3,700 Nm |
| SAE flange sizes (J620) | 6 1/2, 7 1/2, 8, 10 and 11 1/2 inch |
| Hub types | Type 1.4 with feather keyway; type 3.1 with spline bore |
| Components | Elastomer part, hub, circlip DIN 471 and sealing washer |
| Ambient temperature for displacement values | Up to 60 degrees C |
| Storage | Packed in foil, up to 5 years |
Plug-in design and spline connection
The coupling is delivered as a mounted unit with the spline bore already greased. Because the hub is a sliding spline fit, the pump or gearbox can be removed axially without moving the engine. Micro friction on the spline caused by faulty alignment is listed among the causes of breakdown, so the instruction asks for careful alignment, a minimum distance of about 2 mm between the machined faces, and proper greasing of the spline. Displacement values are maximum figures and must not occur in parallel; where radial and angular displacement arise together, only the proportional share of each may be used.
Mounting to the flywheel
The connection flange is centred in the flywheel, the through holes are aligned with the threaded holes, and the screws are tightened in stages to the torque in the instruction. For SAE flywheels, M8 screws of class 8.8 are tightened to 25 Nm and M10 screws to 49 Nm. KTR recommends securing the screws with a medium-strength thread adhesive, taking care that no adhesive touches the elastomer. For drives with piston engines, pumps or compressors, a torsional vibration calculation is needed to confirm the selection, and KTR offers to carry it out on request.
Related KTR products: KTR ROFLEX Fail-Safe Flexible Shaft Coupling, KTR REVOLEX KX Flexible Pin and Bush Coupling, KTR RIGIFLEX-N Steel Laminae Coupling, KTR TOOLFLEX Metal Bellows Coupling, KTR RADEX-NC Backlash-Free Servo Laminae Coupling and KTR ROTEX GS Backlash-Free Servo Coupling.
Documents and quotation
The attached PDF is the KTR operating and assembly instruction for MONOLASTIC. For a quotation provide the engine or motor power and speed, flywheel SAE size or hole pattern, pump shaft spline or keyed bore, and the type of drive. Pumps and hydraulic components for the same applications are listed under Hydraulic Valves and Components, and other couplings under Electric Motors.
Datasheets & Documents
- Operating Instructions KTR MONOLASTIC operating and assembly instructions KTR-N 48510 EN (edition 1) Download
Reviews (0)
About brand
KTR Systems is a German manufacturer of power transmission couplings, brakes and hydraulic components, based in Rheine, Westphalia. It was founded on 30 September 1959 by Franz Tacke, grandson of the founder of the older coupling maker F. Tacke KG, which dated from 1886. KTR's ROTEX jaw coupling, introduced in 1967, became the first brand coupling to be standardised in DIN.
Seven Star LLC is an independent supplier in Muscat. We list KTR coupling ranges with the technical data from the manufacturer operating and assembly instructions, for machine builders and maintenance teams in Oman and the GCC.
KTR company profile
| Founded | 30 September 1959, Rheine, Germany, as Kupplungstechnik GmbH |
|---|---|
| Founder | Franz Tacke |
| Roots | F. Tacke KG, coupling maker in Rheine since 1886 |
| Headquarters | Rheine, Germany |
| Product families | ROTEX jaw couplings, BoWex curved-tooth gear couplings, RADEX-N disc couplings, POLY-NORM couplings, brakes, torque limiters, torque measuring systems, oil coolers and hydraulic bell housings |
Milestones
- 1886: Franz Tacke founds F. Tacke KG in Rheine.
- 1959: Kupplungstechnik GmbH, later KTR, is founded.
- 1967: The ROTEX coupling is introduced.
KTR product series
Flexible couplings include the ROTEX torsionally flexible jaw coupling, the POLY-NORM torsionally flexible coupling, the REVOLEX KX pin and bush coupling for heavy drives, the ROFLEX fail-safe coupling and the MONOLASTIC flexible flange coupling. Torsionally rigid couplings include the BoWex curved-tooth gear coupling and the RIGIFLEX-N steel laminae coupling.
For servo and precision drives there are the ROTEX GS backlash-free jaw coupling, the RADEX-NC servo laminae coupling and the TOOLFLEX metal bellows coupling. The CLAMPEX KTR 603 clamping set provides a keyless shaft-hub connection.
Where KTR couplings are used
Pumps and compressors, fans, gearboxes and conveyors, hydraulic power units, machine tool and servo axes, and heavy drives in steel, mining and cement plants.
KTR products we list
Ordering KTR couplings: what we need
Send the coupling type and size, or the motor power and speed, the shaft diameters and keyways, the torque and shock loads, the shaft displacement expected and the operating temperature. The instructions state rated torque, maximum torque, speed and displacement for each size.
Facts checked against KTR's own history and company profile pages (ktr.com), October 2026.
Browse KTR products by category: Electric Motors, Couplings & Shaft Locking Devices.
FAQ
Questions about the KTR MONOLASTIC Flexible Flange Coupling
Answers from our engineering team on installation, compatibility and integration.
01What is the MONOLASTIC coupling used for?
It connects an engine or motor flywheel to a hydraulic pump or similar machine, damping torsional vibration and compensating shaft displacement.
02Which flywheel sizes does the SAE version fit?
SAE J620 flanges of 6 1/2, 7 1/2, 8, 10 and 11 1/2 inch, depending on the coupling size.
03What elastomer hardness is used?
Elastomer parts are T65 and T70 on the Shore A scale.
04Does it need a torsional vibration calculation?
For drives with diesel engines, piston pumps or compressors the instruction requires one; KTR performs it on request.
05How long can the coupling be stored?
KTR states up to 5 years when kept in its foil packing under dry conditions.
Reviews
There are no reviews yet.