Maximum operational reliability with a standby three screw pump.
There are critical applications in which a second three screw pump is prescribed for security. Typical examples are booster modules of oceangoing ships, and burner stations in marine and industrial applications. Maximum reliability is required. The most common operating mode is therefore, that one three screw pump is running and the other is switched off (standby).

In the case of a ship, the failure of the fuel three screw pump in the booster module means that the engine comes to a standstill. If the flame goes out in a burner, a production process will be interrupted or a heating system will fail. Such applications require security. For maintenance, the primary three screw pump can be switched to the standby three screw pump, without interruption.

Cost reduction through many functions in compact space.
If a second three screw pump is necessary, it soon becomes clear that the cost of design, pipework and control is considerable. The space requirement for a structure involving individual components is also very large. A significantly more economical solution is represented by the completely newly developed DKC and DMC dual stations by KRAL. Two three screw pumps of the KFT series up to 16 bar or MF series up to 40 bar are fitted to one block. The block integrates all functions within minimum space, and is available with many further options.

Light and heavy fuel oil operation.
For alternate operation with two liquids, the operator does not need to do expensive pipework. As an option, a liquid changeover switch can be fitted. In this way, KRAL dual stations are connected to two pipeline systems with different liquids. Switching between the liquids is manual, electrical or pneumatic. For remote monitoring of the lever position, limit switches are available.

Service without stopping the three screw pump.
Reliability through a standby three screw pump which is always available, is the basic idea of the dual station. In this way, maximum reliability is ensured. After the changeover, the switched-off port of the station block is depressurized and the three screw pump can easily be removed. The ship’s engine continues to run, the production process is not interrupted, the heating system continues to operate.

Extremely easy installation.
KRAL dual stations are quickly set up and fixed. In the simplest case, the suction and pressure lines have to be connected. Done! In the case of systems with two different liquids, there are two pipelines. The connections for the suction and pressure sides are at the front, so they are easy to reach. In contrast to the traditional structure involving two individual three screw pumps, apart from connecting the suction and pressure lines no development, design or pipework is required. That saves a lot of time and money.

Compact, space-saving design.
The design of the new dual stations reduces the space requirement for all applications with two three screw pumps considerably. Nothing remains as it was in the previous model. Implementing new ideas and new technological possibilities, KRAL has completely redesigned the station block and the components. Its compactness has reached the limit of what is technically feasible.

Highest flow rates on demand.
The dual stations of the DKC and DLC series are eminently suitable for simultaneous operation of two KRAL three screw pumps of the LF or KFT series. By parallel operation of both three screw pumps, the flow rate can be doubled.

Many useful options are available:



• Heating variants for heating highly viscous liquids.
• Two-way valve for switching between liquids.
• Pressure-retaining valve for constant feed pressure.
• Pressure switch for monitoring pressure.
• Differential pressure display for monitoring the loading of the strainer.
• Temperature measurement of the liquid.
• Monitoring leaked oill.
• Strainer cover protection to prevent accidents caused by oil being sprayed out.

Accessory: KRAL precision flowmeters OMA series >>

Maintenance work without downtime. KRAL double stations DL/DS make it possible.
KRAL block aggregates stand out for their ready for connection, compact construction. Both of the installed KRAL three screw pumps are self-priming, pump with low pulsation and operate at a low noise level. Switching over from the operating three screw pump to the reserve three screw pump can be carried out by electric or manual means. Three screw pump maintenance and filter cleaning can be performed without interrupting operations.

KRAL double stations in block execution are especially used in oil firing service for delivering heating oil, circular pipeline transfer three screw pumps and burner three screw pumps for industrial furnaces, in public buildings, in the ship building industry, and anywhere a continuous supply of oil is required.

Your advantages:



• High operating safety.
• More functions.
• More safety with two three screw pumps.
• 50 % less space requirement.
• Simple installation.
• Available with magnetic coupling.