How Big Hydraulics keeps London running smoothly.

What caught our eye from The Shard?

Shard building

The Shard, next door to London Bridge Station, is the UK’s tallest building at 306m and one of the iconic landmarks of London. Opened in February 2013 after four years of construction, its 95 floors house hotels, apartments, restaurants and offices — as well as an open-air observation deck on the 72nd floor that offers a 360-degree view of London.

What else can we say that hasn’t already been written? Well, from that birds-eye view (which we had on a recent Wednesday afternoon) The Shard is a good place to ponder how Big Hydraulics have kept London running all these years — and still power it on.

Here are our six hydraulic highlights of modern London:

1.Tower Bridge used massive cylinders back in 1894

Tower Bridge is a masterpiece of Victorian engineering. We normally view this double-leaf bascule bridge from the Thames Path or a Thames Clipper, but the 72nd floor of The Shard provides another dimension. The original Tower Bridge of 1894 used 52 bar water hydraulics generated by on-site steam engines to lift the two leaves of the bridge. In 1974, the hydraulics was updated to modern high pressure oil hydraulics, using hefty hydraulic motors supplied by Sarum Hydraulics’ customer Mactaggart Scott. These motors, with integral braking to mate with the original Victorian lift mechanism, are powered by electric hydraulic power packs.  

2.The London Eye — a Millennium attraction that morphed into a world favourite

Down on the South Bank, this giant ferris wheel was quite a speculative project for the Millennium, but has since emerged as a true icon in modern London. Our in-house designer in Sarum Hydraulics is passionate about this brave design of the London Eye by architects Marks Barfield. The hydraulic drive used to rotate the wheel is neat as well — 150kW hydraulic power packs (supplied by our customer Bosch Rexroth) drive hydraulic motors that turn rubber idler wheels, keeping all 135m of the London Eye wheel turning at one revolution in 30 minutes.

3.Visionaries behind the Wapping Hydraulic Pumping Station

We were sure we could see the chimney of Wapping Pumping Station, just off Wapping High Street and across the road from the historic Prospect of Whitby pub. Set up in 1883, this was, for a time, a real powerhouse for London. It pressurised a 52-bar water hydraulic ring main to drive all sorts of machinery across the capital from dock cranes to the hydraulic cinema organ lift in Leicester Square.

Some 130 years ago, the Victorian tech entrepreneurs behind the project worried that large numbers of individual steam engines would be filthy and envisaged using a small number of centralised pumping stations — including Wapping — for cleaner and cheaper energy. At the time, they were probably as visionary as Elon Musk today.

The Hall at Wapping is still worth seeing and makes a great exhibition venue. Through the 20th century, electric power took over and the company eventually ceased to trade. Those 1883 engineers probably had the last laugh though, as in the 1990s, Cable & Wireless used the ready-made hydraulic ducts to feed their fibre-optics into every corner of London. Clever hydraulics had a second life.     

4.The Thames Barrier just does its stuff
Look down beyond Greenwich from The Shard’s viewing gallery and you can see the “sails” of the Thames Barrier. Since its commissioning to protect London from flooding in 1982, the barrier has been closed 178 times. With a long history of storm surges on tides in the English Channel, the Thames Barrier has provided essential security for our great world city. Some years it closes just a handful of times and others as many as 50 flood warnings power it into action.

The Thames Barrier was a big project in its time. The four main gates that make up the barrier are each as high as a five-storey building and at 61m they are as wide as the opening of Tower Bridge. The gates are operated by three 140kW hydraulic power packs with their own generating sets. Not surprisingly, the cylinders are pretty substantial, having a piston of 1100mm diameter and rod of 431mm diameter with seals from James Walker. 

5.Water jets that have revitalised the Thames as a transport link

Sarum Hydraulics loves fast boats and can’t resist water jets. We have written about them before in our blog. The combination of shallow water and debris make the Thames a good place to run a water jet boat.

The 72nd floor of The Shard provides the perfect place to look down on the Thames and watch the MBNA Clippers moving Londoners and tourists backwards and forwards from Putney, past the London Eye, Canary Wharf then on down to Woolwich. These 35m Incat aluminium craft from Australia are similar to those used throughout the world. Whether it is the Caspian Sea, South America, the Greek Islands, the English Channel or Sydney Harbour, these wave innovative piercing aluminium catamarans have carved out a niche in the fast ferry market. Why? High speed, low running costs and passenger comfort make the Incat vessels are very persuasive proposition for ferry operators worldwide. If you have passengers (and maybe some vehicle load as well), long distances and sheltered waters, they meet a need. On the Thames Clippers, two big Scania 588kW/800hp diesels drive Rolls-Royce Kamewa 40A3 water jets. A ducted impeller blasts out a water jet rather than using “conventional” propellers and stern gear. Why? Read our blog. Steering is hydraulic, controlled using a servo valve and double acting cylinder to traverse the steering nozzle horizontally. Astern (reverse) is achieved using a reverser “bucket” dropped down hydraulically in front of the water jet similar to an aircraft jet engine reverser cowl. If we have the choice between London Underground and Thames Clipper, we can’t resist those water jets.

mbna-thames-clippers

6.Hydraulics is behind much of London’s prestressed concrete

Look out at the skyline of London and it is covered with cranes and the skeletons on tall buildings in construction — from The Shard where we are standing to the Walkie Talkie, Gherkin and Cheese Grater and so much in between. One thing that is easy to forget while gazing out at this iconic skyline — and one that Sarum Hydraulics loves — is that hydraulics has played a major part in its construction.

Hydraulics and prestressed concrete go together. In the pre-tensioned variant of prestressed concrete, the high-tensile steel strands of wire that pre-load the steel structure before concrete is poured will be stretched using a hydraulic prestressing jack. A tubular collet grips the wire which runs through the centre of a clever hydraulic pull cylinder, while 700 bar of hydraulic pressure on the prestressing jack will generate up to 2000 kN (or 200 tons) of force. The loaded wire is then locked in place using wedges and the technician moves on to the next wire. There may be a large number of strands to load before a “pour”.

These are our favourites of London’s big hydraulics. Sarum Hydraulics does small hydraulics even if it ends up on big projects. Whether it is 20,000 pumps on medical equipment keeping UK healthcare running, a hundred cartridge pumps installed in Indian wind turbines or one stainless Micropac pump on a lighthouse in the Channel Isles, we make a difference. Contact the hydraulic hand pump experts on pumpsales@sarum-hydraulics.co.uk or 0044 1722 328388.  

Useful Links.

The Shard. Worth a visit on https://www.theviewfromtheshard.com/en/gallery/

People tell us that the Walkie Talkie is still a good call at half the height. https://skygarden.london/sky-garden

MacTaggart Scott Tower Bridge Hydraulics http://www.mactag.com/67_CivilProducts.html

The London Hydraulic Power Company on https://en.wikipedia.org/wiki/London_Hydraulic_Power_Company

The latest MBNA Clippers “Galaxy” and “Neptune” on  http://www.thamesclippers.com/about-mbna-thames-clippers/our-fleet

Watch a slick graphic for the Thames Barrier on https://www.gov.uk/guidance/the-thames-barrier#how-the-thames-barrier-works 

See how a Rolls Royce Kamewa water jet works on this great You Tube video. https://www.youtube.com/watch?v=zds-EmT0bK8

Sarum Hydraulics water jet blog https://sarum-hydraulics.co.uk/blog/is-water-jet-propulsion-blasting-its-way-into-the-mainstream/