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KRAL GmbH
Bildgasse 40 Industrie Nord 6890 Lustenau
Circulation pumps
KRAL screw pumps from the manufacturer for circulation applications.
KRAL develops circulation pumps from the manufacturer for demanding industrial processes in which media must be moved safely, efficiently and continuously. Our solutions are designed as industrial circulation pumps for continuous operation and are suitable as circulation pumps for closed circuits where a stable flow rate is required. Thanks to their robust design, low noise levels and high energy efficiency, our pumps support economical and reliable system management.
In our engineering, we rely on screw pumps, whose technology enables smooth, low-pulsation delivery and even, continuous pumping. As precise positive displacement pumps, they ensure constant performance with different media requirements, for example as circulation pumps for oil, circulation pumps for fuels or circulation pumps for lubricating oil. Our experts take into account parameters such as flow rate, differential pressure, operating pressure and viscosity in order to achieve a high level of operational reliability.
In our engineering, we rely on screw pumps, whose technology enables smooth, low-pulsation delivery and even, continuous pumping. As precise positive displacement pumps, they ensure constant performance with different media requirements, for example as circulation pumps for oil, circulation pumps for fuels or circulation pumps for lubricating oil. Our experts take into account parameters such as flow rate, differential pressure, operating pressure and viscosity in order to achieve a high level of operational reliability.
KRAL manufactures circulation pumps in various designs and sizes for specific customer requirements. Our production facilities create solutions for circulation pumps for marine applications, circulation pumps for booster modules, circulation pumps for separators and circulation pumps for fuel systems. Each pump is manufactured from high-quality materials and undergoes our validation process to ensure long-term process reliability, system availability and ease of maintenance.
KRAL - your expert for circulation pump technology.
"Quality, innovation and speed, at all times and worldwide."
KRAL has positioned itself as a manufacturer of quality products at a fair price/performance ratio since the company was founded. We offer customized circulation pumps for systems, from engineering to commissioning, both locally and worldwide. Our after-sales service is also there for you after the purchase.
See our services for yourself. We are happy to be there for you.
See our services for yourself. We are happy to be there for you.
Advantages of our circulation pumps.
Our circulation pumps from KRAL show their strength where feed pumps have to work permanently, efficiently and reliably. Our experts design them for precise medium delivery, taking energy requirements, pump efficiency and operating conditions into account. This results in solutions for circulation pumps for heating oil, circulation pumps for lubricant systems and other industrial circuits where a constant delivery rate is crucial. Find out more:
- Outstanding energy efficiency.
We design our pumps in such a way that energy consumption remains low and a stable volume flow is achieved at the same time. Thanks to modern materials and coordinated hydraulics, our employees ensure economical fluid delivery and reduce operating costs in sophisticated systems. This not only helps to save costs, but also to protect the environment.
- Durability and reliability.
We manufacture robust industrial pumps that work reliably even under high loads. For applications such as lubricating oil circuits, fuel circuits or sealing oil supply, our technicians test materials, media resistance and sealing concepts to ensure that the circulation pumps maintain their performance over the long term.
- Quiet operation.
Our engineering focuses on precisely designed screw pumps and spindle pumps which, as positive displacement pumps for continuous circulation, enable quiet operation. This makes KRAL circulation pumps also suitable as circulation pumps, recirculation pumps or circulation pumps in noise-sensitive industrial environments.
- Easy installation and maintenance.
Our circulation pumps can be integrated into existing systems as a pump unit, pump module or pump station. Accessible components, matched mechanical seal and optional overflow valve make servicing easier and reduce downtimes.
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Flexible connections
If the outer casing of the screw pump is made of steel, almost any position, direction, size, type and classification of the flange is possible. It can be optimally adapted to any installation situation.
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Housing variants
Depending on the operating requirements, the CG series screw pumps are available with cast iron or steel housings.
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External overflow valve
The overflow valve ensures that the liquid is diverted in the event of overpressure.
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Rotary shaft seal
The CK series screw pump is only available with a radial shaft seal. The CL series screw pump can be equipped with different shaft seals thanks to the longer spindle set. External ball bearings are also possible. This pump line is used as a horizontal or vertical foot pump or flange pump as well as a vertical container pump.
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Seal housing
Depending on the operating requirements, different shaft seals are possible for the CL series. The CL screw pump is the slide-in pump used in the CG series. The different housing options allow enormous flexibility in terms of fluid connections. An optional external overflow valve can be fitted to CG screw pumps.
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Longer spindle set
Thanks to the longer spindle set, external ball bearings are also available as an option.
Advantages of our circulation pumps at a glance.
- Reduced energy consumption and lower operating costs thanks to KRAL design for efficient liquid pumps.
- Conveying large quantities in a small space, even with compact fuel pumps.
- Linear or axial delivery for uniform flow in technical circuits.
- High efficiency thanks to precise spindle geometry from our engineering department.
- User-friendly design with clearly accessible service points.
- Flexible use, for example in hydraulic circuits or coolant circuits.
- Very quiet operation thanks to smooth conveying and coordinated component geometry.
- Minimal wear thanks to robust materials and our validation.
- Very easy to maintain and durable as KRAL media pumps for continuous operation.
- DIN standardization for safe integration into industrial systems.
Do you have any questions? - We will be happy to help you!
We and our independent sales and service partners are available to you worldwide at any time.
Please contact us by phone or e-mail or use our inquiry form and we will get back to you shortly.
Please contact us by phone or e-mail or use our inquiry form and we will get back to you shortly.
Areas of application for our circulation pumps.
Circulation pumps for booster modules.
Our KRAL circulation pumps for booster modules keep the pressure stable in complex systems and ensure a consistent fuel supply. Our project engineers match the flow rate to the module design, medium and operating profile. This makes these booster pumps particularly suitable for industrial processes in which continuous delivery determines the performance of the entire system.
Circulation pumps for lubrication systems.
KRAL circulation pumps support the precise supply of lubricants to machines and systems. As robust lubricating oil pumps, they deliver lubricants evenly and reduce loads on moving components. We validate the design for applications in which a circulation pump for fuels and lubricants measurably supports the service life of the system.
Circulation pumps for separators.
Our circulation pumps for separators improve separation and cleaning processes through reliable fluid circulation. All of our engineers take into account the medium, temperature and viscosity behavior to ensure that process pumps work reliably even under demanding operating conditions. This results in resilient solutions for industrial processes with continuous media movement.
Circulation pumps as sealed oil pumps.
Sealing oil is supplied to the rotating shafts of hydrogen-cooled generators using KRAL three-spindle screw pumps. Depending on the system requirements, our experts recommend the K, L or C series. These auxiliary pumps ensure the supply of sealing oil, reduce wear and increase the operational reliability of the generators.
Do you have any questions about
Circulation pumps
Just send us a short message and we will be happy to answer any questions you may have.
Technical data of our circulation pumps.
L series
Z series
K series
G series
KRAL 'sscrew pumps for power plants provide a resilient solution for pumping lubricants, oil feed pumps and supply pumps in continuous industrial operation. Our G series is available in six sizes and therefore covers a wide performance spectrum for power plants. The low-maintenance operation is a significant advantage for applications in fuel supply and in continuously operating circulation systems.
These power station pumps operate reliably at viscosities of up to 500 mm²/s and temperature ranges from -10 to 120 °C, optionally even up to 300 °C. This makes them suitable for use alongside lubricating oils. This makes them suitable not only for lubricating oils but also as screw pumps for bitumen or circulation pumps for heavy oil and as circulation pumps for media with high viscosity in thermal process plants. Our engineering takes installation space, operating profile and medium into account; the compact design allows use in space-critical applications. All housing parts can be mounted in 90° steps.
Numerous options - from cartridge seals to tank installation variants - make the series adaptable for circulation units, transfer pumps and ring main pumps. Our employees check the design for circulation pumps for closed liquid circuits, while ATEX approval and API 676 conformity support international projects with high safety and standard conformity requirements.
These power station pumps operate reliably at viscosities of up to 500 mm²/s and temperature ranges from -10 to 120 °C, optionally even up to 300 °C. This makes them suitable for use alongside lubricating oils. This makes them suitable not only for lubricating oils but also as screw pumps for bitumen or circulation pumps for heavy oil and as circulation pumps for media with high viscosity in thermal process plants. Our engineering takes installation space, operating profile and medium into account; the compact design allows use in space-critical applications. All housing parts can be mounted in 90° steps.
Numerous options - from cartridge seals to tank installation variants - make the series adaptable for circulation units, transfer pumps and ring main pumps. Our employees check the design for circulation pumps for closed liquid circuits, while ATEX approval and API 676 conformity support international projects with high safety and standard conformity requirements.
C series
CK series
CL series
CG series
W series
| Technical data | 15-26 | 32-54 | 55-85 | 105-118 | |
|---|---|---|---|---|---|
| Qth (1450 min-1, 0 bar) | l/min | 15-26 | 32-54 | 55-85 | 105-118 |
| Max. Pressure flange | bar | 120 | 120 | 120 | 120 |
| Temperature max. pumped liquid | °C | ||||
| with radial sealing ring NBR | 90 | 90 | 90 | 90 | |
| with radial sealing ring FKM | 150 | 150 | 150 | 150 | |
| with mechanical seal standard | 150 | 150 | 150 | 150 | |
| with mechanical seal hard material | 180 | 180 | 180 | 180 | |
| Magnetic coupling | 300 | 300 | 300 | 300 | |
| Viscosity | mm²/s | ||||
| min. | 1 | 1 | 1 | 1 | |
| max. | 100000 | 100000 | 100000 | 100000 | |
| Max. Pressure suction flange | bar | ||||
| with radial sealing rings | 6 | 6 | 6 | 6 | |
| with mechanical seal standard | 6 | 6 | 6 | 6 | |
| with mechanical seal hard material | 6 | 6 | 6 | 6 | |
| Magnetic coupling | 6 | 6 | 6 | 6 |
DKC / DLC / DS/L series
DKC series.
DLC series.
DS/L series.
Frequently asked questions about our circulation pumps
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