Swing Bridge

HISTORY OF THE SWING BRIDGE

SWING BRIDGE FACTS

THE SWING BRIDGE IS THE FOURTH BRIDGE BUILT OVER THE TYNE ON THE SAME SITE.

• 23 September 1868 – Construction of Swing Bridge begins.

The first, constructed of wood and stone about the year 120 A.D. by the Roman Emperor Hadrian. This bridge stood until 1248 when it was destroyed by fire, which also destroyed a great part of the town. The second Mediaeval Bridge was of stone construction and stood from the year 1320 until a section of it was washed away in the great flood of 1771. The remaining portions had to be removed and the third bridge, constructed of stone with nine arches, was completed in 1781. This bridge was removed by the Commission to make way for the construction of the Swing Bridge.

The Swing Bridge was built by the River Tyne Improvement Commission – the predecessors of the Port of Tyne, under powers conferred by the Tyne Improvement Act of 1861, as part of their overall plan for improving navigation and expanding trade by opening the upper reaches of the river to larger vessels.

The design for the new bridge was drawn up by John Ure, Resident Engineer of the Tyne Improvement Commission.

Sir W G Armstrong & Co. was appointed contractor for the project with William Armstrong himself assisting in the design of the bridge and his company manufacturing and installing the wrought iron superstructure and all the hydraulic operating machinery.

The bridge was designed in such a way as to swing open around a central pivot to create two unobstructed waterways on either side of its main central pier, to allow ships to move more freely upriver.

• 15 June 1876 – Swing Bridge opens to road traffic.

• 17 July 1876 – Swing Bridge opens to river traffic. The first ship to pass through the bridge was the Europa on her way to take on board the 100-ton gun built by Armstrong at Elswick Engine and Ordnance Works for the Italian Government.

• Since that occasion the Bridge has opened over 286,281 times (and growing) allowing some 448,090 vessels to pass through.

• Originally four hours’ notice was required from a ship’s captain before the bridge could be opened. Today the Port of Tyne Harbour Master gives 24 hours’ notice to the Swing Bridge staff.

• 1924 – was the busiest year for the bridge when it opened 6,000 times. Sadly now river traffic in the upper reaches of the Tyne is less frequent the bridge now opens for visiting yachts and pleasure craft and the first Wednesday of each month for maintenance swings.

• Preparations for swinging the bridge today takes 30 minutes.

• A full revolution of the bridge takes around 6 minutes.

• The original cost of the Swing Bridge was £240k around £24m in today’s money over 100 times as much.

• From its original construction a heat-wave could close the bridge when the metal expanded and ‘welded’ it to its mountings, forcing the fire brigade to be called to douse it with water. The solution from the 1960s was to paint it using a light reflecting paint.

• About 3,000 litres of paint are needed to cover the 15,000 square metres of the bridge.

Port of Tyne Maritime House Tyne Dock South Shields Tyne and Wear NE34 9PT

Swing Bridge c1920

@Port_of_Tyne T. +44 (0) 191 455 2671 www.portoftyne.co.uk

Printed on 100% recycled paper

SWING BRIDGE

WELCOME TO THE SWING BRIDGE THE SWING BRIDGE IS ONE OF THE MOST WELL-KNOWN OF THE SEVEN BRIDGES LINKING NEWCASTLE AND GATESHEAD AND CERTAINLY THE MOST WELL-USED, HOWEVER MANY PEOPLE HAVE NO IDEA THEY ARE CROSSING A SCHEDULED ANCIENT MONUMENT. The mechanism used to swing the bridge is kept in working order by its custodians the Port of Tyne and is still the same machinery originally installed by Sir W G Armstrong.

The upper road section of the bridge is maintained by Newcastle City Council as the competent Highways Agency while the mechanism and structure of the bridge is maintained by the Port of Tyne.

HOW THE SWING BRIDGE WORKS

Swing Bridge Engine Room

THE BRIDGE IS 171M LONG AND 14M WIDE AND CONSISTS OF SIX SPANS, FOUR OF WHICH ARE OVER THE RIVER AND TWO OVER LAND. THE TWO CENTRE SPANS MAKE UP THE SWINGING PORTION, WHICH IS 85M LONG AND WEIGHS ABOUT 1300 TONS, THIS CANTILEVERED SPAN IS ABLE TO MOVE THROUGH 360° TO ALLOW VESSELS TO PASS ON EITHER SIDE OF THE BRIDGE WHEN OPEN. The foundations are concrete filled cast iron cylinders set in the river’s bedrock, granite piers rest upon the cylinders at a little above the height of low water. The weight of the swinging portion of the bridge is carried by the centre pier.

When turning about 900 tons of the total weight of 1300 tons of the swinging portion is supported by an hydraulic centre press which reduces the effects of friction and wear and tear on the forty-two 9144mm diameter rollers which turn on a roller path of about 13m diameter. The bridge when open to road traffic is supported at the end by cast iron blocks moved and locked into position under the girders by hydraulic rams.

The power for operating the bridge is supplied by hydraulic engines worked by electrically driven pumps to a pressure of about 49 kg cm2 and all machinery is duplicated as an insurance against breakdowns.

Pressurised water is used to power the hydraulic engines which turn the bridge. The process begins in the Pump Room (located on the east side of the bridge) where water is stored and pressurised and then is transferred into an Accumulator or energy store. There are two Accumulators on the Swing Bridge but only one – the east accumulator -is used today. It can be filled with water in 2 – 3 minutes and provides sufficient energy to swing the bridge between 1 – 1.5 times.

The process continues in the Engine Room (located on the west side of the bridge) where both water engineering and mechanical engineering come into play. Armstrong’s original water engines, crankshafts and gears still work smoothly together to produce the necessary force to swing the central part of the bridge.

WELCOME TO THE SWING BRIDGE THE SWING BRIDGE IS ONE OF THE MOST WELL-KNOWN OF THE SEVEN BRIDGES LINKING NEWCASTLE AND GATESHEAD AND CERTAINLY THE MOST WELL-USED, HOWEVER MANY PEOPLE HAVE NO IDEA THEY ARE CROSSING A SCHEDULED ANCIENT MONUMENT. The mechanism used to swing the bridge is kept in working order by its custodians the Port of Tyne and is still the same machinery originally installed by Sir W G Armstrong.

The upper road section of the bridge is maintained by Newcastle City Council as the competent Highways Agency while the mechanism and structure of the bridge is maintained by the Port of Tyne.

HOW THE SWING BRIDGE WORKS

Swing Bridge Engine Room

THE BRIDGE IS 171M LONG AND 14M WIDE AND CONSISTS OF SIX SPANS, FOUR OF WHICH ARE OVER THE RIVER AND TWO OVER LAND. THE TWO CENTRE SPANS MAKE UP THE SWINGING PORTION, WHICH IS 85M LONG AND WEIGHS ABOUT 1300 TONS, THIS CANTILEVERED SPAN IS ABLE TO MOVE THROUGH 360° TO ALLOW VESSELS TO PASS ON EITHER SIDE OF THE BRIDGE WHEN OPEN. The foundations are concrete filled cast iron cylinders set in the river’s bedrock, granite piers rest upon the cylinders at a little above the height of low water. The weight of the swinging portion of the bridge is carried by the centre pier.

When turning about 900 tons of the total weight of 1300 tons of the swinging portion is supported by an hydraulic centre press which reduces the effects of friction and wear and tear on the forty-two 9144mm diameter rollers which turn on a roller path of about 13m diameter. The bridge when open to road traffic is supported at the end by cast iron blocks moved and locked into position under the girders by hydraulic rams.

The power for operating the bridge is supplied by hydraulic engines worked by electrically driven pumps to a pressure of about 49 kg cm2 and all machinery is duplicated as an insurance against breakdowns.

Pressurised water is used to power the hydraulic engines which turn the bridge. The process begins in the Pump Room (located on the east side of the bridge) where water is stored and pressurised and then is transferred into an Accumulator or energy store. There are two Accumulators on the Swing Bridge but only one – the east accumulator -is used today. It can be filled with water in 2 – 3 minutes and provides sufficient energy to swing the bridge between 1 – 1.5 times.

The process continues in the Engine Room (located on the west side of the bridge) where both water engineering and mechanical engineering come into play. Armstrong’s original water engines, crankshafts and gears still work smoothly together to produce the necessary force to swing the central part of the bridge.

HISTORY OF THE SWING BRIDGE

SWING BRIDGE FACTS

THE SWING BRIDGE IS THE FOURTH BRIDGE BUILT OVER THE TYNE ON THE SAME SITE.

• 23 September 1868 – Construction of Swing Bridge begins.

The first, constructed of wood and stone about the year 120 A.D. by the Roman Emperor Hadrian. This bridge stood until 1248 when it was destroyed by fire, which also destroyed a great part of the town. The second Mediaeval Bridge was of stone construction and stood from the year 1320 until a section of it was washed away in the great flood of 1771. The remaining portions had to be removed and the third bridge, constructed of stone with nine arches, was completed in 1781. This bridge was removed by the Commission to make way for the construction of the Swing Bridge.

The Swing Bridge was built by the River Tyne Improvement Commission – the predecessors of the Port of Tyne, under powers conferred by the Tyne Improvement Act of 1861, as part of their overall plan for improving navigation and expanding trade by opening the upper reaches of the river to larger vessels.

The design for the new bridge was drawn up by John Ure, Resident Engineer of the Tyne Improvement Commission.

Sir W G Armstrong & Co. was appointed contractor for the project with William Armstrong himself assisting in the design of the bridge and his company manufacturing and installing the wrought iron superstructure and all the hydraulic operating machinery.

The bridge was designed in such a way as to swing open around a central pivot to create two unobstructed waterways on either side of its main central pier, to allow ships to move more freely upriver.

• 15 June 1876 – Swing Bridge opens to road traffic.

• 17 July 1876 – Swing Bridge opens to river traffic. The first ship to pass through the bridge was the Europa on her way to take on board the 100-ton gun built by Armstrong at Elswick Engine and Ordnance Works for the Italian Government.

• Since that occasion the Bridge has opened over 286,281 times (and growing) allowing some 448,090 vessels to pass through.

• Originally four hours’ notice was required from a ship’s captain before the bridge could be opened. Today the Port of Tyne Harbour Master gives 24 hours’ notice to the Swing Bridge staff.

• 1924 – was the busiest year for the bridge when it opened 6,000 times. Sadly now river traffic in the upper reaches of the Tyne is less frequent the bridge now opens for visiting yachts and pleasure craft.

• Preparations for swinging the bridge today takes 30 minutes.

• A full revolution of the bridge takes around 6 minutes.

• The original cost of the Swing Bridge was £240k around £24m in today’s money over 100 times as much.

• From its original construction a heat-wave could close the bridge when the metal expanded and ‘welded’ it to its mountings, forcing the fire brigade to be called to douse it with water. The solution from the 1960s was to paint it using a light reflecting paint.

• About 3,000 litres of paint are needed to cover the 15,000 square metres of the bridge.

Port of Tyne Maritime House Tyne Dock South Shields Tyne and Wear NE34 9PT

Swing Bridge c1920

@Port_of_Tyne T. +44 (0) 191 455 2671 www.portoftyne.co.uk

Printed on 100% recycled paper

SWING BRIDGE