David Kirkaldy
Encyclopedia
David Kirkaldy was a Scottish engineer who pioneered the testing of materials as a service to engineers during the Victorian period. He established a test house in Southwark
, London
and built a large hydraulic tensile test machine, or tensometer
for examining the mechanical properties of components, such as their tensile strength
and tensile modulus or stiffness
.
in Scotland
in 1820. He worked at Robert Napier’s Vulcan Foundry Works in Glasgow, and moved from workshop to drawing office. As a result of the industrial revolution, new materials were being developed such as steel
to replace cast iron
and wrought iron
. The properties of these materials were not well understood. In conjunction with his work for Napier and Sons, Kirkaldy undertook a long series of tensile load tests between 1858 and 1861. He published his Results of an Experimental Inquiry into the Comparative Tensile Strength and other properties of various kinds of Wrought-Iron and Steel in 1862.
firm of Greenwood & Batley, closely supervising its production. Aggrieved over the slow rate of manufacture, after fifteen months he had it delivered to London still unfinished, in September 1865. The testing machine is 47 feet 7 inches long, weighs some 116 tons, and was designed to work horizontally, the load applied by a hydraulic cylinder
and ram. The machine is still held in working order at the Kirkaldy Museum in Southwark
.
), together with other equipment he developed. He set up business in Southwark in 1866, performing tests for external clients on materials used in engineered structures such as bridges. The business moved to a nearby purpose-built building at 99 Southwark Street, London in 1874. The present ground floor of the building is a museum to his work, with many of his machines still in working order. The famous inscription above the door reads Facts not Opinions. With the many failed products either from his own tests or collected on site, he opened a "Black Museum" of failed products and components on the top floor of the building, but it was unfortunately destroyed in the London Blitz of 1940. Fractured samples from the Tay Bridge disaster
were probably stored and exhibited in the museum.
He developed ways of examining the microstructures of materials using a simple optical microscope
after polishing and etching specimens taken from components.
He famously tested many samples taken from the first Tay railway bridge for the official Inquiry on the Tay Bridge Disaster
. He confirmed that the wrought iron tie bar
s failed at their connections to the cast iron columns of the bridge, when he tested intact tie bars with complete lugs still attached. The attachments were cast iron lugs which fractured at the bolt holes, and numerous fractured lugs were found after the disaster lying on the piers. The critical strengthening elements were much weaker than had been supposed by Thomas Bouch
, the engineer of the first bridge. They failed at about 20 tons tensile load rather than the specified 60 tons, and were a prime cause of the collapse of the bridge on 28 December 1879. Since he tested several samples of each of the lower and upper lugs, he was able to show that they exhibited a range of strengths, the lowest results being caused by defects like blow holes in the cast metal. Thus some of the upper lugs were actually weaker than the strongest lower lugs, an observation confirmed by damage shown on the remains left on the piers after the disaster. He tested the wrought iron tie bars themselves, and they proved tough, as specified, although only slightly stronger than the cast iron lugs to which they were attached. The high girders were also made of wrought iron and had a very high tensile strength
. They were found after the accident at the bottom of the Tay estuary and relatively little damaged compared with the cast iron columns which supported them. Some were reused in local houses, and when they were demolished in the 1960s, some were removed to the Royal Museum of Scotland in Edinburgh
, where they are on public display.
He died in 1897, and was succeeded by his son in the family business.
Southwark
Southwark is a district of south London, England, and the administrative headquarters of the London Borough of Southwark. Situated east of Charing Cross, it forms one of the oldest parts of London and fronts the River Thames to the north...
, London
London
London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...
and built a large hydraulic tensile test machine, or tensometer
Tensometer
A tensometer is a device used to evaluate the Young's modulus of a material and other tensile properties of materials, such as tensile strength. It is usually a universal testing machine loaded with a sample between 2 grips that are either adjusted manually or automatically to apply force to the...
for examining the mechanical properties of components, such as their tensile strength
Tensile strength
Ultimate tensile strength , often shortened to tensile strength or ultimate strength, is the maximum stress that a material can withstand while being stretched or pulled before necking, which is when the specimen's cross-section starts to significantly contract...
and tensile modulus or stiffness
Stiffness
Stiffness is the resistance of an elastic body to deformation by an applied force along a given degree of freedom when a set of loading points and boundary conditions are prescribed on the elastic body.-Calculations:...
.
Career
David Kirkaldy was born near DundeeDundee
Dundee is the fourth-largest city in Scotland and the 39th most populous settlement in the United Kingdom. It lies within the eastern central Lowlands on the north bank of the Firth of Tay, which feeds into the North Sea...
in Scotland
Scotland
Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...
in 1820. He worked at Robert Napier’s Vulcan Foundry Works in Glasgow, and moved from workshop to drawing office. As a result of the industrial revolution, new materials were being developed such as steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...
to replace cast iron
Cast iron
Cast iron is derived from pig iron, and while it usually refers to gray iron, it also identifies a large group of ferrous alloys which solidify with a eutectic. The color of a fractured surface can be used to identify an alloy. White cast iron is named after its white surface when fractured, due...
and wrought iron
Wrought iron
thumb|The [[Eiffel tower]] is constructed from [[puddle iron]], a form of wrought ironWrought iron is an iron alloy with a very low carbon...
. The properties of these materials were not well understood. In conjunction with his work for Napier and Sons, Kirkaldy undertook a long series of tensile load tests between 1858 and 1861. He published his Results of an Experimental Inquiry into the Comparative Tensile Strength and other properties of various kinds of Wrought-Iron and Steel in 1862.
Testing Materials
Kirkaldy left Napier in 1861 and over the next two and a half years studied existing testing techniques and designed his own testing machine. Entirely at his own expense, he commissioned this machine from the LeedsLeeds
Leeds is a city and metropolitan borough in West Yorkshire, England. In 2001 Leeds' main urban subdivision had a population of 443,247, while the entire city has a population of 798,800 , making it the 30th-most populous city in the European Union.Leeds is the cultural, financial and commercial...
firm of Greenwood & Batley, closely supervising its production. Aggrieved over the slow rate of manufacture, after fifteen months he had it delivered to London still unfinished, in September 1865. The testing machine is 47 feet 7 inches long, weighs some 116 tons, and was designed to work horizontally, the load applied by a hydraulic cylinder
Hydraulic cylinder
A Hydraulic cylinder is a mechanical actuator that is used to give a unidirectional force through a unidirectional stroke. It has many applications, notably in engineering vehicles.- Operation :...
and ram. The machine is still held in working order at the Kirkaldy Museum in Southwark
Southwark
Southwark is a district of south London, England, and the administrative headquarters of the London Borough of Southwark. Situated east of Charing Cross, it forms one of the oldest parts of London and fronts the River Thames to the north...
.
New Testing House
The machine still exists in the old test house at Southwark (now the Kirkaldy Testing MuseumKirkaldy Testing Museum
The Kirkaldy Testing Museum is a museum in Southwark, south London, England, located on the site of David Kirkaldy's testing works. It houses Kirkaldy's huge testing machine, along with many smaller more modern machines...
), together with other equipment he developed. He set up business in Southwark in 1866, performing tests for external clients on materials used in engineered structures such as bridges. The business moved to a nearby purpose-built building at 99 Southwark Street, London in 1874. The present ground floor of the building is a museum to his work, with many of his machines still in working order. The famous inscription above the door reads Facts not Opinions. With the many failed products either from his own tests or collected on site, he opened a "Black Museum" of failed products and components on the top floor of the building, but it was unfortunately destroyed in the London Blitz of 1940. Fractured samples from the Tay Bridge disaster
Tay Bridge disaster
The Tay Bridge disaster occurred on 28 December 1879, when the first Tay Rail Bridge, which crossed the Firth of Tay between Dundee and Wormit in Scotland, collapsed during a violent storm while a train was passing over it. The bridge was designed by the noted railway engineer Sir Thomas Bouch,...
were probably stored and exhibited in the museum.
He developed ways of examining the microstructures of materials using a simple optical microscope
Optical microscope
The optical microscope, often referred to as the "light microscope", is a type of microscope which uses visible light and a system of lenses to magnify images of small samples. Optical microscopes are the oldest design of microscope and were possibly designed in their present compound form in the...
after polishing and etching specimens taken from components.
Tay Bridge Disaster
Tay Bridge disaster
The Tay Bridge disaster occurred on 28 December 1879, when the first Tay Rail Bridge, which crossed the Firth of Tay between Dundee and Wormit in Scotland, collapsed during a violent storm while a train was passing over it. The bridge was designed by the noted railway engineer Sir Thomas Bouch,...
. He confirmed that the wrought iron tie bar
Tie bar
There have been many forms of tie-control devised since the 19th century, when ties first became a regular part of fashion. Clips, chains, pins have all been used to do one simple thing: to keep a tie from flapping, falling or otherwise presenting anything other than a neat appearance...
s failed at their connections to the cast iron columns of the bridge, when he tested intact tie bars with complete lugs still attached. The attachments were cast iron lugs which fractured at the bolt holes, and numerous fractured lugs were found after the disaster lying on the piers. The critical strengthening elements were much weaker than had been supposed by Thomas Bouch
Thomas Bouch
Sir Thomas Bouch was a British railway engineer in Victorian Britain.He was born in Thursby, near Carlisle, Cumberland, England and lived in Edinburgh. He helped develop the caisson and the roll-on/roll-off train ferry. He worked initially for the North British Railway and helped design parts of...
, the engineer of the first bridge. They failed at about 20 tons tensile load rather than the specified 60 tons, and were a prime cause of the collapse of the bridge on 28 December 1879. Since he tested several samples of each of the lower and upper lugs, he was able to show that they exhibited a range of strengths, the lowest results being caused by defects like blow holes in the cast metal. Thus some of the upper lugs were actually weaker than the strongest lower lugs, an observation confirmed by damage shown on the remains left on the piers after the disaster. He tested the wrought iron tie bars themselves, and they proved tough, as specified, although only slightly stronger than the cast iron lugs to which they were attached. The high girders were also made of wrought iron and had a very high tensile strength
Tensile strength
Ultimate tensile strength , often shortened to tensile strength or ultimate strength, is the maximum stress that a material can withstand while being stretched or pulled before necking, which is when the specimen's cross-section starts to significantly contract...
. They were found after the accident at the bottom of the Tay estuary and relatively little damaged compared with the cast iron columns which supported them. Some were reused in local houses, and when they were demolished in the 1960s, some were removed to the Royal Museum of Scotland in Edinburgh
Edinburgh
Edinburgh is the capital city of Scotland, the second largest city in Scotland, and the eighth most populous in the United Kingdom. The City of Edinburgh Council governs one of Scotland's 32 local government council areas. The council area includes urban Edinburgh and a rural area...
, where they are on public display.
He died in 1897, and was succeeded by his son in the family business.