KRAL Three Screw Pumps K Series

The economical, most sold KRAL pump

Universal use up to 230 psi. K series pumps are universal three screw pumps, making them the most sold KRAL pump. The K pumps have a feed pressure of 16 bar and housing made from nodular cast iron. They are approved for use onboard ships. In addition, they are equipped with sealed external bearings that are pre-lubricated for their lifetime so they are not stressed by the material being pumped and require no maintenance.

Operation, materials, components

• Delivery rate: 1.5 to 770 gpm
• Delivery rate KFT: 1.3 to 135 gpm
• Max. differential pressure: 230 psi
• Temperature range: -5 °F to 360 °F,
  magnetic coupling to 570 °F
• Housing: Nodular cast iron EN-GJS-400
• Spindles: Steel, nitrided
• Certifications: ABS, BV, CCS, DNV, GL, LRS, MRS, NK, RINA
• ATEX: II 2 GD b/c group II, category 2
• Heating: Electrical, fluid media and steam

How the K three screw pump fits into the KRAL product program

How the K three screw pump fits into the KRAL product program. The K series three screw pump is available with DIN flanges in an inline configuration, and the KFT series three screw pump is available with DIN flanges at the top. Various installation methods are possible for flange-mounting, pedestal and base three screw pumps.

Advantages of three screw pumps

Compared to other types of pumps, KRAL three screw pumps offer high capacity without taking up much space. This applies in particular at high differential pressure. The three screw pumps are self-priming, with low pulsation delivery and can be easily regulated. The single three screw pumps, single stations and double stations are extremely compact. All K three screw pumps have an internal safety valve.

Stop coupling damage

With some liquids, residue can build up, which may cause the pump to fail. A typical spot for residue to build up is at the mechanical seal. The residue damages the ball bearing, which runs hot, melts the elastomeric ring and damages the coupling. With the K series three screw pump, there is a weep hole next to the mechanical seal, to prevent the fluid from collecting and building up as residue.

The new generation three screw pumps series K has been thoroughly reengineered. As the most sold universal three screw pump series K offers a number of benefits. The three screw pump prevents the accumulation of residue forming fluids by locating the leakage hole before the ball bearing. Secondly, KRAL offers the advanced quality of SiC mechanical seals, which contains graphite, as a solid lubricant to reduce the coefficient of friction in dry running conditions. The O rings with high fluorine content are suitable for higher temperatures and are chemically stable. The three screw pump series K offers innovative seal concepts. A proven selection of radial rotary shaft seals, mechanical seals and a hermetically sealed magnetic coupling are available as standard. A robust and compact design rounds off the profile.