Körting Marine Ejector
Spare Parts Supplier
Water-driven ejectors from Körting Hannover in bilge, ballast and sewage piping: no moving parts, each one designed for its own system, so the plate, the arrangement drawing and the service it does on board are read before a nozzle or diffuser is quoted.
Where Körting ejectors work on a ship
Körting does not sell its ship ejectors from a list of fixed sizes. Each one is designed for the conditions of the project, and the duties below are the spaces Körting itself names for them. The service is therefore the most useful way to group an enquiry: it tells the desk which drawing the ejector appears on and what is likely to have reached it through the suction.
Bilge ejectors
Bilges and engine rooms come first among the spaces Körting names for its bilge ejectors. The ejector is driven by seawater from one of the ship's own pumps and has no motor or shaft of its own, so ejector parts and anything needed on the supplying pump are separate lines.
Ballast tank, cofferdam and forepeak ejectors
Körting lists ballast tanks, cofferdams and the forepeak among the spaces its ejectors empty. An ejector reaches the residual water a centrifugal pump leaves behind, which is why one often sits on the stripping side of a ballast system and appears on the ballast piping diagram rather than in the engine-room drawings.
Chain locker and bow thruster ejectors
Chain lockers and bow thruster rooms are on Körting's list too. These ejectors sit far from the engine room, often in spaces that are hard to reach, and the photograph of the plate is usually the first thing missing from the enquiry, so ask for it before the ship leaves port.
Grey and black water ejectors
Körting also names grey and black water among the media its ship ejectors handle. Here the suction side carries solids and fibre, so a blocked nozzle or mixing section is a more likely cause of lost suction than on a clean ballast line, and the medium belongs on the request.
Why a Körting ejector ends up in an enquiry
Körting describes its ship ejectors as having no moving parts and no dynamic seals, and as safe against dry running, so they do not wear the way a pump does. When one stops drawing, the cause is usually on the driving side or in a part that has been blocked or damaged.
Driving-water pressure below the design point
Körting points out that an ejector's performance depends on the pressures at its motive, suction and discharge connections, which is why it asks for them when sizing one. A supplying pump that has lost head, a valve left partly closed or a fouled strainer on the driving line takes suction away without any fault in the ejector. Gauge readings from the time it stopped drawing belong on the request before a nozzle is ordered.
Blocked or damaged nozzle
The motive nozzle is where the driving water speeds up, and its bore is the narrowest point in the line. Debris that passes the strainer can lodge there, and a nozzle that has been cleared with a tool may no longer hold its original bore. That is the point at which a replacement nozzle is asked for.
Cracked or damaged castings
A body cracked by frost or impact, a diffuser damaged while the line was being worked on, or corroded flange faces are the cases where more than a set of joints is needed. The removed part, its markings and its connection sizes are then the reference for the request.
Ejector components that appear on RFQ lines
An ejector is three main parts in one line: a motive nozzle, a head with the suction connection and a diffuser. Most requests concern one of these or the joints between them, and items in the surrounding piping are identified and quoted separately.
- Motive (driving) nozzles, matched to the bore of the nozzle removed
- Diffusers and mixing sections
- Ejector heads (bodies) with the suction connection
- Joints between nozzle, head and diffuser, and flange gaskets at the three connections
- Flange bolting sets for the driving, suction and discharge connections
- Complete replacement ejectors, quoted against the original project data
- Wear parts of the pump that supplies the driving water, as their own lines
- Piping-side items identified separately: suction non-return valve, driving-water valve, pressure gauges and strainer elements
What identifies a Körting ejector
Because each Körting ship ejector is designed for its own system, the request has to describe that system as well as the ejector. The list below is what turns an enquiry for ejector spares into parts that can be quoted. How a plate photograph becomes a priced list is set out on the how we work page.
- Photograph of the plate with every line as stamped, including any order or project number
- The service: bilge, engine room, ballast tank, cofferdam, chain locker, bow thruster space, forepeak, or grey or black water
- The driving medium and the pump that supplies it, with a photograph of that pump's own plate
- Nominal size and flange standard at the driving, suction and discharge connections
- The arrangement drawing, or the bilge or ballast piping diagram on which the ejector is shown
- Gauge readings at the driving and discharge connections from the time the ejector stopped drawing
- Photographs of the removed nozzle and diffuser with any markings, and their measured bores if a part has to be made to sample
What a Körting ejector enquiry is read against
An ejector with no moving parts still produces a fair number of wrong orders, mostly because a nozzle is ordered before anyone has checked the driving side. These points are settled before anything is quoted.
Matched to the project
Körting designs each ship ejector individually for the operating conditions of its system. A nozzle from another ejector of the same nominal size may not match the bore of the one fitted, so the original project data or the removed part is the reference, never the size alone.
Driving side checked first
Gauge readings and the state of the supplying pump are asked for before ejector parts, so the ship does not replace a nozzle to cure a pump fault. Where the pump is the problem, its parts are handled through marine pump spare parts.
Ejector and piping kept apart
Non-return valves, the driving-water valve, gauges and strainers belong to the piping, not to the ejector. They are quoted on their own lines against their own markings, so the order for the ejector stays small and exact.
Not every ejector on board is a Körting
The brine and air ejector inside a freshwater generator is part of that generator, as on the Alfa Laval JWP. A bilge or stripping ejector with an Ellehammer plate belongs to Iron Pump, and the ejector in a vacuum toilet collecting unit to Evac. The plate decides which page the request belongs to.
Körting ejector enquiries — recurring questions
Does Körting make ejectors for ships?
Yes. Körting Hannover, the jet pump maker founded in Hanover in 1871 by Berthold and Ernst Körting, builds bilge and ballast ejectors for ballast tanks, bilges, engine rooms, chain lockers, bow thrusters, cofferdams and forepeaks, and ejectors for grey and black water. They are driven by water from the ship's own pumps and have no moving parts.
Why is there no catalogue number for a Körting ship ejector?
Körting designs each ship ejector for the operating conditions of its project rather than selling fixed catalogue sizes. The plate, any order or project number on it and the arrangement drawing are what identify the ejector, and the removed nozzle and diffuser are the fallback when the paperwork is missing.
Our bilge ejector has stopped drawing. Which part should we order?
Usually none until the driving side is checked. Körting notes that an ejector's performance follows the pressures at its driving, suction and discharge connections, so read the gauges, check the supplying pump, the valves and the strainer, then open the ejector. If the nozzle is blocked or its bore has been damaged, send its photograph and measured bore with the plate data.
Is an ejector the same thing as an eductor?
On board the two words are used for the same water-driven jet pump. Some industries keep eductor for a unit driven by a liquid and ejector for one driven by steam or air, but a bilge or stripping unit is called either. For identification the plate and the service matter more than the word.
Will an Ellehammer nozzle fit a Körting ejector?
They are different makers' designs: the Ellehammer range belongs to Iron Pump. Even where the nominal connection sizes agree, each nozzle and diffuser is sized for its own design point, so parts are not crossed between the two without the original data or the removed parts.
Is Vessel Core connected to Körting?
No, and there is no agreement of any kind. Vessel Core holds no distribution, representation or partnership agreement with Körting, and quoting a component against one of its designations implies no approval by the maker and no claim of interchangeability.
Send the plate, the service and the gauge readings.
List the plate data, the space the ejector serves, the supplying pump, the connection sizes, the parts needed and the port. Nozzles, diffusers, joints and piping items are quoted as separate lines, so the ship can decide what to fit now and what to keep as a spare.
