Bilge pump

As Lenzen ( Low German lens = " empty") is generally described as the pumping of water from a water vehicle or in civil engineering.

Watercraft

Is pumped out in water transport, the water that is in a leak or even during normal operation in the lower part of a ship's hull, the bilge collects.

Also the ballast water of large cargo ships, which gives them when driving without stability is pumped out. Due to environmental problems caused by entrained in foreign waters organisms, the ballast tanks are usually pumped out in deep waters of the lake and filled with water from the open sea again until the introduction of filtering measures.

Bilge pump

Often this is called a bilge pump, bilge pump also ( Bilge ) called for use, which is usually optimized to transport high volumes of water, and not to produce very high pressures. The safety requirements for recreational craft shall require that at least one bilge pump shall be a hand pump. If water enters the hull, there is a significant risk that the batteries with which the electric pumps are operated, wet and fail because they are, for practical reasons, very deep in the hull.

Meanwhile, however, there are also other vehicles as ships on bilge pumps, for example, some tanks (such as the Leopard 2 ), which can then traverse waters safe.

Lenz flap

Lenz Lenz dampers or valves are mostly manually operated valves opening, creating with the help of small pleasure boats penetrated water overboard. The bilge valves are below the water table ( 420 dinghy, laser ... ), in this case the Lenzen is possible only with sufficient speed. You work ( principle of a water jet pump ) due to the suction effect which is established with the drive through the water. They do not work at too great a height difference between the cockpit floor and the water surface. If either the speed too low or if the bilge flap too deep, the water flows back into the boat, if that is not prevented by a check valve.

Inventor of (also called self- bailers ) Lenz flaps Paul Elvstrøm, the most successful sailors in Denmark.

• Self bailers

Lenz flap

Side Lenz flap of a Dyas

Top: Closed Bottom: open ( Interior )

Self-bailing cockpit

A selbstlenzendem cockpit is called in sailboats, the cockpit floor located above the water surface, and thus an easy opening to the outside is sufficient to take over splash board. In modern racing yachts practice has been to open the entire aft, so even large amounts of water, as they can penetrate at crushers, for example, be derived quickly. For larger yachts (eg for offshore racing ), therefore, is located at the rear of only one degree in the form of a simple railing to prevent someone is washed overboard. All built according to the currently valid CE Seetauglichkeitseinstufung sport boats should have cockpits and wells, " the self-draining or have other means (are) prevent the penetration of water into the boat interior ."

Drainage pipes

On smaller yachts in the cockpit floor is to the rear and sides often. Large diameter pipes an then connect the ground with the fuselage and so lead the water directly into the sea.

Lenzen by Pütz or bailer

Technical means for Lenzen, as bilge pumps can fail. For example, the intake clog or break down the power supply. For these cases are at least two buckets with a leash by the handle, also referred to as Pütz or Schlagpütz be carried on board. With such Pütz effectively larger amounts of water can be drawn from a ship.

In special cases, such as on very small dinghies such as the Last Optimist sailboat that comes with sailors also known bailer used.

Civil engineering

In civil engineering, one has to contend primarily with groundwater, but also rain water at cloudbursts. With little water entering the excavation or tunnel, the water continually pumped ( water retention ) is.

At high water table and deep excavations to Beat sheet piling or secures the excavation by similar measures. Then the earth will be excavated to the desired depth below the water level, sealed the pit with underwater concrete and this secured with anchors against buoyancy. Then can be commenced with the Lenzen. In the statics have to be made ​​to the thereby changing within a short time load status into consideration. In the dry excavation can then be continued as usual.