Anderton boat lift
The Anderton Boat Lift ( English Anderton Boat Lift ) is the first hydraulic boat lift (plunger lift) in the world. It was named after the nearby village of Anderton in Cheshire in northwestern England . It connects the River Weaver with the Trent and Mersey Canal .
The ship lift , built in 1875, was in operation for more than 100 years until it was closed in 1983 due to corrosion . Restoration began in 2001 and reopened in 2002.
Economic framework
Rock salt was mined in Cheshire as early as Roman times. By the end of the 17th century, numerous salt mines had been built around the so-called salt towns of Northwich , Middlewich , Nantwich and Winsford . In order to be able to transport the salt away, the River Weaver was made navigable from its confluence with the River Mersey up to Winsford by 1734 . With the Trent and Mersey Canal, a second transport route was created in 1777. This canal, built for narrowboats , ran partially parallel to the Weaver, but about 15 meters above the river valley. He opened up the area further south around Stoke-on-Trent , with its coal mines and the ceramics and porcelain industry, which grew rapidly from the 18th century.
Instead of competing with each other, the operators of these two waterways decided to cooperate. In 1793, a harbor basin was created at Anderton on the north bank of the Weaver immediately below the embankment, on the upper edge of which the Trent and Mersey Canal ran. With the help of chutes, cranes and inclined lifts , salt and other goods were reloaded between the two waterways.
history
planning
By 1870, the Anderton harbor basin had developed into an important cargo handling point. The constant reloading of goods between the two waterways turned out to be extremely time-consuming and costly. For this reason, the operators of the Weaver shipping route considered it necessary to connect the two waterways. Initially, a lock staircase was thought of, but the loss of water from the higher canal would have been too great. Therefore, in 1870, they proposed building a boat lift. However, the canal's owner at the time, the North Staffordshire Railway Company , did not want to share in the costs, which is why the Weaver operators ultimately decided to bear the total cost alone.
The operating company then commissioned its chief engineer, Edward Leader Williams , to create designs for a ship lift. Leader Williams explored different approaches and finally decided on a design with two water-filled troughs to counterbalance each other. This principle had already been implemented on the Grand Western Canal in 1835 , where a total of seven lifts had been built, in which the troughs were each connected to one another by three chains running over pulleys . However, an extremely massive support structure was required to support the weight of both water-filled troughs. Leader Williams therefore planned not to hang the troughs on chains, but instead to support them on plungers that move up and down in underground hydraulic cylinders filled with water . This meant that the superstructure was only required for lateral guidance of the troughs. After the decision for a hydraulic operation had been made, Leader Williams commissioned the experienced hydraulic engineer Edwin Clark with the actual planning. The lift was to be built on a small island in the Anderton harbor basin.
technology
The two wrought-iron troughs were each 22.9 meters long, 4.7 m wide, 2.9 m high (1.5 m water depth) and could each accommodate two narrowboats of the 72-foot class (21.9 m long). Each trough had an empty weight of 90 tons and weighed 252 tons when full. (Due to the Archimedean principle , it does not matter whether there are ships in the trough or not.) Each trough was carried by a single hydraulic cylinder consisting of a 15.2 m long cast iron piston with a diameter of 90 cm, which is located in an underground , also moved cast iron cylinder with a diameter of 1.7 m.
The superstructure consisted of seven hollow, cast-iron pillars on which guide rails for the troughs were attached, a work platform as well as stairs and walkways for the operating personnel. At the bottom of the river, the troughs were lowered directly into the water of the harbor basin so that no gates were necessary here. At the upper end, a 50 meter long, wrought iron canal bridge connected the Trent and Mersey Canal.
In normal operation, the water level in the upper trough was set slightly higher than in the lower trough. Then a pressure line was opened between the two cylinders. The upper trough, heavier due to the higher water level, sank slowly and in the process pushed water out of its cylinder through the pressure pipe into the other cylinder, thus lifting the lower trough upwards. In addition, a hydraulic accumulator was available in order to be able to move the troughs independently of one another at the beginning and end of a journey. A steam-powered hydraulic pump pressurized the reservoir. It was also possible to lift the troughs completely independently with the help of the accumulator and the steam pump. However, such an independent lifting process took around 30 minutes, around ten times longer than normal.
construction
Planning permission was granted in July 1872 and construction began in late 1872. After around 30 months of construction, the elevator was opened to traffic on July 26, 1875.
Problems with the hydraulics
The lift worked perfectly for the first five years, operations were only interrupted when the canal froze. But in 1882 one of the cylinders burst when it was raised with a boat in it. The trough then quickly lowered. However, there were no injuries and the superstructure remained undamaged. During subsequent checks, the second cylinder also burst, whereupon the elevator was closed for six months. During this time the cylinders were replaced and the pressure lines revised.
Traffic via the elevator increased steadily towards the end of the 19th century despite growing competition from the railroad. However, there were always problems with the hydraulic cylinders. The stuffing boxes at the top of the cylinders had to be replaced in 1891 and 1894. However, the main problem was corrosion on the pistons, which led to the formation of scoring. The reason for this was the relatively high acidity of the canal and river water, which was used as a working medium, due to the discharge of industrial waste water. After an attempt to repair these grooves with copper only worsened the corrosion of the surrounding iron due to electrochemical processes, the elevator was finally converted in 1897 to use distilled water. However, this only slowed the corrosion. During the years that followed, maintenance and repair work increased more and more, and each time the elevator either had to be completely blocked for several weeks or could only work with one trough and thus reduced efficiency.
Conversion to electrical operation
In 1904, a long-term closure was imminent, as both hydraulic cylinders including the pistons and the steam engine urgently had to be replaced. The operating company therefore commissioned its then chief engineer Colonel JA Saner to look for alternatives. Saner suggested replacing the hydraulic cylinders with a system of counterweights and pulley blocks driven by electric motors. Although this increased the number of moving parts considerably, they were all arranged above ground and thus more easily accessible for maintenance and repair work than the underground hydraulic system.
However, since both the weight of both troughs and that of the newly added counterweights had to be borne by the superstructure, it had to be considerably reinforced. However, Saner promised to achieve this by building a separate, stronger superstructure around the existing structure and thus only need three short closing times.
The new superstructure consisted of ten steel frame structures, five on each side of the elevator. These carried a machine floor 18 meters above the river. Electric motors, drive shafts and winches were installed here. The two troughs were preserved and were connected by wire ropes with 18 cast iron counterweights each. Since each counterweight weighed 14 tons, the mass of the filled trough was precisely compensated for, and the electric motor was only used to overcome friction and accelerate and brake. At the lower end, the basins in which the troughs landed were concreted, equipped with gates and thus drained so that the pistons and stuffing boxes were no longer exposed to the aggressive river water. The canal bridge was also reinforced.
This work was carried out between 1906 and 1908. And as Saner had promised, the elevator was only blocked three times for a short time during these two years, for a total of 49 days. The converted elevator was officially opened on July 29, 1908.
Operation after the changeover
After switching to electrical operation, the ship lift was successfully in operation for 75 years. Of course, regular maintenance work also took place now, in particular the wire ropes were prone to material fatigue due to the constant bending loads and had to be replaced relatively often. The new superstructure also proved to be susceptible to corrosion and had to be painted with a mixture of tar and rubber every eight years.
Between 1941 and 1942 the hydraulic cylinders that had been left in the ground during the renovation were removed so that the iron could be used for other purposes, probably for war purposes.
With the strong growth of road traffic after the Second World War, freight traffic with narrowboats on the British canal system steadily decreased and came to a complete standstill in the mid-1960s. Around 1970, the Anderton ship lift was therefore almost only used for recreational boating during the summer season. In 1979 the building was placed under monument protection.
closure
In the course of painting work in 1983, severe corrosion damage was discovered in the superstructure, which is why the elevator was declared dilapidated and closed. Counterweights, pulleys and gears were dismantled in 1987 and stored next to the elevator.
restoration
Ten years after the closure, a foundation, the Anderton Boat Lift Trust , was set up to raise funds for an operational restoration of the Anderton lift. Numerous other organizations participated in the project and work finally began in 2001.
During the restoration, the elevator was switched back to hydraulic operation. Modern hydraulic cylinders were used and hydraulic oil was no longer used as the working medium. The counterweights, which were no longer necessary, were dismantled and used as components for a maze. However, the superstructure from 1908 with the machine floor and the rollers was retained.
In September 2002 the Anderton boat lift was reopened. For visitors who do not come with their own boat, tours through the elevator are offered with a tour boat.
The boat lift cannot be visited in winter.
literature
- Eckhard Schinkel, Sven Bardua: Ship lift . The world's ship lifts. People - technology - history. In: Landschaftsverband Westfalen-Lippe, Westfälisches Industriemuseum (Hrsg.): Writings of the Westfälisches Industriemuseum Dortmund . tape 22 . Klartext, Essen 2001, ISBN 3-88474-834-3 .
- Hans-Joachim Uhlemann: The history of the ship lifts . DSV-Verlag, Hamburg 1999, ISBN 3-88412-291-6 (together with Verlag Busse-Seewald, Herford ).
- David Carden: The Anderton Boat Lift . Black Dwarf Publications, Lydney 2000, ISBN 0-9533028-6-5 .
Web links
- Official website of the boat lift
- Anderton Boat Lift ; The Heritage Trail
- Waterway News on the reopening after the restoration
- Pictures and reports from the reopening at Canal Junction
Individual evidence
- ^ M. Clarke: Anderton Boat Lift: Restoring the Cathedral of the Canals. (DOC) Thomas Telford Ltd., accessed February 10, 2011 .
- ^ Sue Wilkins: Northwich: The Town With That Sinking Feeling. TimeTravel-Britain.com, accessed February 10, 2011 .
- ^ Anderton Boat Lift back in action. Northwest Regional Development Agency, September 10, 2002, archived from the original on November 27, 2010 ; accessed on September 17, 2008 (English).
Coordinates: 53 ° 16'22 " N , 2 ° 31'50" W.