Background

Treating carbon steel components to improve their surface properties such as hardness via the carburising process is a well established technology. And yet even today, after many years of development, variations in the carburising quality and therefore the hardness at the surfaces of the parts being treated are still problems for heat treaters and component manufacturers. With ever increasing competitive pressures, such as the need to meet higher quality standards and lower costs, such problems need to be addressed to ensure that furnaces operate at maximum productivity and with minimum levels of rejects. A new mass flow controller system that has been developed by Air Products and implemented on a customer’s furnace seems set to achieve just that by eliminating process variations and providing high quality, uniform carburising.
Problems Leading to Variations in Carburising

The problematic variation in carburising quality is caused by the monitoring and control systems used to run the carburising furnace and regulate the atmosphere and temperature. Common control systems work by measuring the furnace temperature and the oxygen partial pressure. This allows the carbon potential – a measure of the carbon available in the furnace atmosphere for carburising - to be calculated and maintained, as long as the level of carbon monoxide (CO) is known. The actual CO level is not normally measured in real time in the furnace, but is instead set manually in the controller, as are the flow rates of the gases making up the atmosphere in the furnace. However, in both endothermic atmospheres and manually regulated nitrogen-methanol atmospheres, variations in these supposedly fixed variables can occur in a number of ways. These include poor regulation of gas flows, changes in the composition of the natural gas, pressure variations in the nitrogen and methanol lines, and so on.
Using Mass Flow Controllers to Control Furnace Atmospheres

Using the new system from Air Products, in which a nitrogen-methanol atmosphere is regulated by mass flow controllers (MFCs), overcomes these problems and improves carburising quality. Mass flow controllers can regulate the flow rates independent of furnace pressure and temperature, compensate for all variations in the line pressures, and keep the blend of gases - and therefore the CO level in the furnace constant. The system, first developed three years ago, includes the calculated CO level, derived from the gas flow rates into the furnace, in the calculation of the carbon potential of the furnace, and therefore enables a much more accurate and uniform process. Using this mass flow controller technology also offers the opportunity to use the accelerated carburising process (ACP), which can shorten the carburising cycle by up to 20% and significantly increase productivity. Accelerated carburising process uses a higher carbon potential, making the need for accurate regulation of the atmosphere more important.
Mass Flow Controller Technology in Industrial Applications

Trials showing the feasibility and benefits of using the new mass flow controller technology and accelerated carburising process have been carried out recently with one of Air Products’ customers, Mubea, in Germany, in one of the company’s chamber furnaces. Mubea was interested in increasing the production rate of a new component in its hardening furnace, and consequently installed mass flow controller panels, and combined accelerated carburising process with the new process control system for carbon potential regulation. The trials have been very successful, and Mubea has also installed a mass flow controller panel on a continuous working carburising furnace. In addition, there is now an ongoing project at another customer’s site, in which the mass flow controller technology and accelerated carburising process has been linked with an existing carburising control system in a furnace. Start up took place at the end of last year and the results to date are very promising.
The Carburing Process

Although the success of the new control system relies on very fine tuning of the process, the basics of carburising are relatively simple. The process itself can be divided into two phases - carbon deposition and carbon diffusion. During deposition, the carbon-containing species from the furnace atmosphere are transferred to the surface of the steel component being treated and decompose to give carbon. The main component containing carbon in carburising atmospheres is CO, and the rate of the process is influenced by process temperature and atmospheric composition. This highlights the importance of tight control of these variables using the new mass flow controller technology. In the diffusion phase, the deposited carbon diffuses into the steel component from the surface. This process is only dependant on temperature, and not the composition of the atmosphere.
The Carburing Atmosphere Inside the Furnace

Endothermic atmospheres for carburising are produced by partial burning of natural gas and air, to give a mix containing 20% CO and 40% hydrogen, the rest made up of nitrogen and residual carbon dioxide and water. Problems with costs and reliability of these atmospheres mean that most heat-treaters now use the direct injection of nitrogen and methanol to produce the carburising atmosphere. By cracking methanol directly in the furnace, variable compositions of carburising atmospheres can be created - and although traditionally the blend is 20% CO and 40% hydrogen, the CO level can be increased to as much as 33% for accelerated carburising. This higher level of CO leads to a higher carbon potential inside the furnace, and so a shorter time is needed to deposit the same amount of carbon, making the process more efficient. Clearly, though, the control needs to be extremely accurate.
How the System Works

The new mass flow controller provides this and, together with the accelerated carburising process, can be installed as a complete atmosphere control system including a control of the carbon potential. mass flow controller technology can also be implemented in existing systems, if control of the carbon potential already exists. The control unit is based on a PC for the visual interface, parameter setting and documentation of the process. For each furnace a hardware controller is used that directly communicates with the PC. This controller regulates the carburising process independent from the PC and so maintains control over the atmosphere even if the PC is shut down. The regulation of the carbon potential is based on the reading from an oxygen probe, the measured temperature and the CO level in the atmosphere, which is calculated from the nitrogen and methanol flow rates. In some cases, an additional CO analyser can be installed. The mass flow controller technology enables the CO level to be changed in the different steps of a carburising cycle, especially for accelerated carburising process

Background

This article summarises the international development of cathodic protection of steel in concrete. The technology was developed in Europe and the USA for applications to buried prestressed concrete water pipelines (Refs. 1 & 2) and in California to deal with deicing salt attack of reinforced concrete bridge decks, and has been widely applied throughout North America for that purpose. It has been used and further developed in the UK to deal with a variety of problems ranging from buildings with cast in chlorides to bridge substructures contaminated with deicing salts and to marine structures and tunnels. It is also widely used on buildings and car parks in UK and Northern Europe. In the Middle East, severe corrosion problems caused by high levels of salinity in soils as well as marine conditions have lead to many large projects being carried out. It has also been used extensively in the Far East including Australia, Japan and Hong Kong.
North America

The USA, Canada and The Netherlands share the distinction among major Organisation of Economic Co-operation and Development (OECD) countries of not requiring the application of waterproofing membranes on major highway bridges although they apply deicing salts in the winter. This has lead to severe corrosion damage on US and Canadian Highway bridges. In 1955 the US Transportation Research Board found that concrete deterioration was rated fourth in a survey of major maintenance problems on bridges. By 1960 it was coming to the fore. The cost of corrosion induced repairs on bridges alone in the USA was estimated at US$20 billion in 1992 (Ref. 3).
Cathodic Protection

In 1959 Richard Stratfull of California Department of Transportation (Caltrans) reported that he had installed an experimental cathodic protection (CP) system on a bridge support beam (Ref. 4). Later he reported that, in 1972, he had installed a more advanced system on a bridge deck. (Ref. 5) The anode system was based on a conventional impressed current CP system for pipelines, but “spread out’ over a bridge deck. The conventional pipeline system was corrosion resistant silicon iron “primary” anode in a backfill of conductive carbon coke breeze.

Stratfull modified this by adding the coke breeze to asphalt. He applied silicon iron anodes at l2ft (3.66m) centres on the concrete bridge deck and then overlaid the anodes with a 3 inch (76mm) conductive asphalt wearing course. That system was energised in 1972 and operated for over 20 years. When surveyed in 1983 the system was working well even though some cracks and delaminations had been repaired before the cathodic protection system installation with insulating polymers that prevented current flow to all areas. Two similar systems installed in the mid 1970s are believed to be still operating.

One of the problems with this particular CP anode system was that US bridge decks were not originally designed for overlays. There was a requirement for an anode that did not change the profile of the bridge and did not increase the deadload. A slotted anode system was developed which put anodes into slots cut into the deck. The most successful deck anodes are now titanium based with mixed metal oxide coatings, either as ribbon in slots or as mesh under an overlay. The anode is supplied in various configurations, principally expanded mesh or strips. These systems are widely applied to bridge and car park decks.
Conductive Organic Coatings

Meanwhile the corrosion problem had been progressing from bridge decks to bridge substructures. Early experiments with conductive organic coatings showed the importance of optimum formulation and application conditions. Similarly, work with activated titanium mesh anodes in sprayed concrete overlays emphasised the requirements for quality of work in respect of preparation of the concrete surface and application of overlays.
Thermally Sprayed Zinc Coatings

Caltrans came to the fore again by developing thermal sprayed zinc applied to bridge substructures. This system was somewhat more durable than conductive coatings, without the requirement for a perfectly dry surface. The use of arc sprayed zinc on the 10,000m2 substructure of the Yaquina Bay bridge in Oregon in 1992 is one of the largest single substructure CP projects undertaken in the USA. It is still operating satisfactorily in 2001.

The Strategic Highway Research Program (SHRP) undertook an extensive survey of the CP systems on North American bridges in 1988-89. They found 840,000m2 of concrete surface under cathodic protection on the US and Canadian interstate highway system. SHRP wrote a review of the survey (Ref. 6), a state of the art report (Ref. 7) and a manual of practice (Ref. 8) for impressed current cathodic protection.
Sacrificial Anodes

The most recent developments have been in the evolution of galvanic or sacrificial anode systems. In the late 1970s experiments were carried out on bridge decks. Some were more successful than others, but none were seriously pursued. However, when corrosion was found on five bridge substructures in the Florida Keys, Florida DoT decided to experiment with arc sprayed zinc and several clamp on zinc systems (Ref. 9). These have been widely used in Florida. Of the 100,000m2 of thermal sprayed zinc systems in the USA, approximately 50% are galvanic systems in marine environments (see CPA Monograph No. 6, Ref. 10).

In Canada, the use of conductive organic coating anode systems on car parks (particularly deck soffits) is very widespread, particularly to private car parks attached to apartment buildings. There is a significant quantity of mesh and other anode systems applied to bridges and other structures. The original Caltrans systems were still extensively used until the mid 1990s.

Present estimates are that over 1½ million square metres of cathodic protection systems have been applied to North American structures and buildings. The type of structure by approximate order of volume is:

· Bridge Decks

· Bridge Substructures

· Car Parking Structures

· Wharves etc.

· Buildings (particularly on the Florida Coast)

There is a recommended practice for cathodic protection published by the US National Association of Corrosion Engineers (Ref. 11), and a test method for embedded anodes (Ref. 12).
The United Kingdom

By 1984 in the UK there was increasing concern regarding the costs of repair and maintenance of buildings and highway structures arising from corrosion of reinforcement. Cathodic protection of steel in soils and waters had been a well established and scientifically well understood engineering discipline since the 1940’s to the extent that it was (and remains) mandatory for buried pipelines carrying dangerous products and for many offshore facilities.

Early work by the Transport Research Laboratory, Spencer & Partners, Taywood Engineering, Harwell and others indicated that the largely pragmatic practical application to reinforced concrete in North America did have fundamental merit and was worthy of scientific investigation, controlled trials and careful implementation. The most significant of this early work in UK was the TRL programme to determine the efficacy of cathodic protection applied to trial blocks and the DoT/G Maunsell & Partners field trial at Gravelly Hill (Spaghetti Junction). These involved cathodic protection of four motorway slip road support structures and the parallel monitoring of two similar structures which were similarly repaired but not provided with cathodic protection.

Since this pioneering work in 1985 the UK market for reinforced concrete repair projects involving cathodic protection has grown from a spend of some £100,000 per annum to an estimated £20m per annum in 1993/94. Some 200,000m2 of cathodic protection has been applied to date in the UK according to the CPA database. Over 500 crossheads have been protected on the Midland Links motorway system alone.

UK industry and research has been significant in its contribution to effective pre-standards (Concrete Society/Icorr Technical Reports 36 & 37, Refs. 13 & 14), leading to the recently published European Standard EN12696:2000 (Ref. 15). The CPA is also working with the National Highways Authorities in England, Scotland, Wales and Northern Ireland on a Bridge Advice Note for Cathodic Protection of Highway Bridges. A full selection and range of cathodic protection systems and services is now available from UK members of the CPA.

A recent innovation in the UK has been the application of cathodic protection to steel framed masonry clad early 20th century buildings and structures. Over ten such structures have had cathodic protection applied in the last decade. These range from small gate structures to a Grade A listed government office building in Scotland with over 80 separate cathodic protection zones.
Continental Europe
Denmark

Northern Europe has seen cathodic protection applied to a significant number of structures. Denmark has two manufacturers of the control and monitoring systems used for CP of reinforced concrete structures, one of which also supplies anodes too. It is therefore not surprising that Denmark leads the field with over 60 installations with considerable activity in other Nordic countries. At present, activity is centred on swimming pools in Denmark with new installations being commissioned at a rate of about 8-10 a year; the anodes being installed in the pool walls. Other applications are car parks and bridge supports.
Norway

Norway also has an indigenous supplier and installer of a proprietary conductive coating anode system, primarily for use on car parks and buildings. Norway is mostly using CP on wharves, bridges and car parks with a few swimming pools. About 10 car park projects have been completed in the last few years. Conductive coating based CP systems have also been in use on four coastal bridges over the last 8 years. Remedial work is continuously going on to control corrosion of reinforcement on chloride contaminated balconies. To date many balconies have been treated successfully.
The Netherlands

In a recent paper it was estimated that about 20 structures in the Netherlands have been subjected to cathodic protection over the past 10 years (Ref. 16). These were predominantly buildings with cast in chlorides. Several had prestressed elements in them. Galvanic cathodic protection using a zinc sheet with a conductive hydrogel adhesive has also been used on precast concrete beams in housing projects (Ref. 10).
Switzerland and Italy

In Switzerland a number of tunnels and bridges have had cathodic protection applied. It is estimated that over 10,000m2 of cathodic protection had been applied up to 1997 (Ref. 17). Italy has used cathodic protection rather differently. It has applied over 150,000m2 of cathodic protection to new decks on autostrade bridges as a preventative technique. In many cases the bridges contained prestressed elements. Much of this work was done between 1990 and 1993.

There is a strong expectation that the publication of the European Standard on cathodic protection for steel in concrete (Ref. 15) will lead to wider application of CP as local and national governments will be provided with the tools to specify cathodic protection where appropriate.
The Middle East

In the Middle East, the prevalence of salt in the soil, air, water and cast into concrete means that up to 74% of reinforced concrete structures show significant corrosion damage after as little as ten to fifteen years (Ref. 18). Many structures have to be rebuilt every ten years or so unless extensive rehabilitation or repair is carried out. Cathodic protection has been used on a number of large marine structures as well as buildings, and industrial plants in Saudi Arabia, Kuwait, Oman, Dubai, the United Arab Emirates and elsewhere. The total area of anode exceeds half a million square metres, and may be as high as a million square metres.
The Far East

Systems were installed in Australia and Hong Kong as early as 1996. There is cathodic protection on new and old sections of the supports surrounding the Sydney Opera House (Ref. 19). A number of bridges, wharves and other structures have received CP amounting to more than 50,000m2. In New Zealand the National War Memorial Carillon Tower has been cathodically protected along with a few jetties. Similarly Hong Kong, with its large coastal exposure has had extensive systems applied to wharves and bridges. There are also installations in South Korea, Singapore, and a large number of small experimental installations in Japan.

BHP Steel have added another 6 colours to their range of Colorbond® Steel. The latest range of Colorbond products also benefit from advances in super polyester pre-painted coating technology.

The new colours cover the complete tonal range from grey, through green, blue red and cream. The most recent colour additions increase the range to 20. They have been designed to be suitable for all kinds of building applications from inner city to rural living.

The colours have also been tested to ensure that they can retain their quality and performance under harsh Australian conditions.

Exxon Mobil Upstream Research, Nippon Steel Corp and Mitsui and Co have jointly developed a new steel which is 20-50% stronger than currently used pipeline steels. To this end, the three companies have signed a letter of intent to commercialise the alloy.

As part of the commercialisation agreement, it is possible Nippon Steel will have their pipe mill upgraded.

The alloy was first developed by Exxon Mobil, who then collaborated with Nippon Steel to make commercial production viable.

The new high strength pipe steel is suited to applications such as natural gas pipelines, which will allow them to be built over longer distances at lower cost. With natural gas usage growing, and resources being located remotely from usage centres, lower cost pipelines could help to make such ventures more economically viable.

The Brugger Test

To the present day there is no common standardized process for testing the toughness and hardenability of case-hardened steel. Decades ago, the Zahnradfabrik (ZF) Friedrichshafen developed a process with which these parameters were tested for the release of the corresponding molten masses. This test, which is used by many manufacturers and users of case-hardened steels, is known in the steel business as the “Brugger test”.

An impact flexure test is performed to determine the toughness. A special specimen with lobed ends (which can be interpreted as realistic models of a cogwheel) is mounted so that the impact fin strikes the broad surface of the fin at an angle less than 30 degrees. This simulates the impact loading of a cog.

The dynamic force at break is the characteristic parameter for impact toughness. It is the maximum force of the recorded force-time characteristic for an impact test. The instrumented pendulum impact tester RKP 450 from Zwick, Ulm, which is designed for a maximum impact energy of 450 Joules, is optimally suited for this test. The specimen is gripped in a special 2-screw clamping shell which allows reactionless clamping. A special baseplate for exchangeable grips as well as the pendulum’s interchangeable impact fins makes it possible to use the impact pendulum tester for the Brugger Test as well as for the usual impact bending tests to Charpy.

The impact fin with its applied strain measurement strips (SMS) is highly stressed during this test. For that reason it is manufactured from high-strength steel. A special heat treatment makes it particularly resistant to wear. It is easily removed for reworking or exchange.

The force-time characteristic during the test is acquired, processed, and evaluated with a high measurement frequency and a resolution of more than 65,000 measurement points. The underlying hardware and software package applied for this is, of course, testXpert® from Zwick.

Scientists from the U.S. Department of Energy’s Brookhaven National Laboratory, Center for Environmental and Molecular Sciences, and Stony Brook University (SBU) have developed a simple, safe method of removing uranium from contaminated metallic surfaces using citric acid formulations so that the materials can be recycled or disposed of as low-level radioactive or non-radioactive waste. The research is published in the July 1, 2005 issue of Environmental Science and Technology.

Decontamination of radionuclides from metallic and other surfaces contaminated by radiological incidents is a major environmental challenge. Brookhaven scientist A.J. Francis, assisted at the Lab by Cleveland Dodge and by Gary Halada at SBU, led the effort in developing an innovative and improved process for decontaminating metal surfaces and other materials. The research team developed an environmentally friendly green-chemistry process that uses all naturally occurring materials – citric acid, common soil bacteria, and sunlight. Present methods of removing uranium from contaminated metal surfaces include sand blasting, chemical extraction, and electro-chemical dissolution. These methods generate secondary waste streams, creating additional disposal problems.

“In the event of a radiological incident, such as a ‘dirty bomb,’ this technology can be used to clean up contaminated materials,” Francis said. “It will also treat the secondary waste generated from the treatment process, resulting in waste minimization. It is a comprehensive process.”

Using the National Synchrotron Light Source, a source of intense x-rays, ultraviolet and infrared light at Brookhaven Lab, the researchers systematically examined the contaminated materials at the molecular scale and the association of uranium before and after treatment with citric acid formulations. The efficiency of uranium removal ranged from 68 percent to 94 percent, depending on the age and extent of corrosion.

Wastewater generated from the decontamination process was subjected to biodegradation followed by photodegradation, which minimized the generation of secondary waste and allowed the uranium to be recovered. This process, which has been patented, can also be used to remove toxic metals and radionuclides from contaminated soils, wastes, and incinerator ash.

The research was funded by the Environmental Management Science Program of the Environmental Remediation Sciences Division, Office of Biological and Environmental Research of the Department of Energy’s (DOE) Office of Science. DOE’s Environmental Management Science Program supports basic research to clean up DOE legacy sites and the technologies that have emerged from the program can also be used in response to radiological incidents.

Scientists at the University of Virginia have announced the discovery of a non-magnetic amorphous material that is three times stronger than conventional steel and has superior anti-corrosion properties. A future variation of the new material, called DARVA-Glass 101, could be used for making ship hulls, lighter automobiles, tall buildings, corrosion-resistant coatings, surgical instruments and recreational equipment. The scientists say commercial use of the material could be available within three to five years.

The material, made up of steel alloys that possess a randomised arrangement of atoms -- thus “amorphous steel” -- was discovered by modifying an earlier version of amorphous steel known as DARVA-Glass 1 reported by the U.Va. researchers at the Fall 2002 meeting of the Materials Research Society. In May of this year they reported on DARVA-Glass 101 in the Journal of Materials Research.

“Amorphous steels can potentially revolutionise the steel industry,” said Joseph Poon, professor of physics at U.Va. and principal investigator for the team that has discovered the material and is now making alterations of it for possible future use in mass production.

Poon’s U.Va. co-investigators are Gary Shiflet, professor of materials science and engineering, and Vijayabarathi Ponnambalam, materials physicist. Their amorphous steel project at U.Va is sponsored by the Defense Advanced Research Projects Agency’s Structural Amorphous Metals Program.

According to Poon, researchers have been trying for years to make amorphous steel in sizes large enough to have practical use. The U.Va researchers have succeeded in producing large-size amorphous steel samples that can be further scaled up. They achieve this by adding a small dose of a rare earth element or yttrium to DARVA-Glass 1. The researchers believe that the large size rare earth or yttrium atom causes destabilisation of the competing crystal structure wherein the significant atomic level stress can lead to the formation of the amorphous structure. These discoveries make the U.Va. researchers optimistic that the material will be economically available within the decade.

In a separate work, a group led by C.T. Liu, a materials scientist at the Oak Ridge National Laboratory in Tennessee, has also reported on large size amorphous steel similar to DARVA-Glass 101 in the June issue of Physical Review Letters, also by modifying the DARVA-Glass 1 discovered by the U.Va scientists.

Poon said the amorphous steel is extremely strong, but brittle in its current state. “We need to toughen the material more,” he said. “We can always make it better.”

According to the U.Va. researchers, amorphous steel can be machined as well as manipulated like a plastic. “It can be squeezed, compressed, flattened and shaped.” Poon said.

The material is of particular interest to the Navy for making non-magnetic ship hulls, particularly for submarines, which are detectable by the magnetic field of their hulls. The amorphous steel that the U.Va. team is refining is non-magnetic, potentially making a ship invisible to magnetism detectors and mines that are detonated by magnetic fields. The new material also may be useful for producing lighter but harder armour-piercing projectiles. The publicly traded company Liquidmetal Technologies owns an exclusive license to the amorphous steel invented by the U.Va. scientists.

BASF has signed an exclusive cooperation agreement with the British-Canadian company Intelligent Engineering Ltd. (IE) for further development of the innovative Sandwich Plate System^™ (SPS). The SPS technology, jointly developed by BASF Group company Elastogran and IE, is rapidly becoming established in the shipbuilding industry for the repair and construction of ship segments. New SPS applications for the civil engineering market are now being developed and a SPS licensee has already completed an initial reference project with the construction of a road bridge in Canada.

“We responded to the needs of our customers in the construction industry,” said Dr. John Feldmann, member of the Board of Executive Directors of BASF Aktiengesellschaft, when asked to explain the background to the new application for the high-tech material. “Our intention was to develop a genuine alternative to conventional steel bridge construction that would be more cost-effective and of the highest quality. We achieved precisely that with SPS.”

Because of their sandwich structure – steel-polyurethane-steel – SPS components are much less susceptible to corrosion than conventional constructions. SPS structures are also lighter and faster to build and also offer built-in protection against fire and vibration. In the case of the road bridge, built by SPS licensee Canam Manac Group Inc., in Saint Martin de Beauce, Quebec, Canada, SPS reduced the weight of the 22 meter bridge deck by 60 percent compared with concrete. And there are no negative effects on the stability of the bridge construction – on the contrary. “Our SPS polyurethane is extremely stable and does not become brittle with age. This makes SPS structures more durable than conventional solutions,” said Georg Knoblauch, who is in charge of SPS technology development at Elastogran.

This reference project in Canada opens up a second high-growth SPS market for BASF and IE. A number of bridge projects are currently under development around the world. For example, ThyssenKrupp Technologies, a SPS licensee, is currently evaluating the feasibility of the system for the construction of mobile bridge elements suitable for use at roadwork sites. SPS elements for this application are currently being subjected to repetitive stress testing at BASF’s laboratories in Ludwigshafen. The Steel Construction Department of the Aachen University of Technology (RWTH) is monitoring the test process as an independent scientific institution.

Elastogran and Intelligent Engineering are also collaborating on other applications where the outstanding material properties of the patented technology can be utilized. For instance, SPS offers many potential benefits for the construction of sports stadiums and arenas. “SPS bleachers or stands are 70 percent lighter than conventional concrete structures and are very effective at absorbing the vibrations induced when thousands of fans jump to their feet to celebrate a goal,” explained Knoblauch. This weight saving may also help in the design of earthquake-resistant buildings.

BASF is a world leader in technology for polyurethane specialties. The Elastogran Group is responsible for BASF’s polyurethanes business in Europe. BASF and Elastogran expect increasing SPS applications to result in substantial growth in the global market for polyurethane specialties. Polyurethanes are versatile plastics with a huge range of applications and their properties can be customized to suit individual uses. Polyurethane products are used in the automotive industry, for thermal insulation in construction and refrigeration technology, in the electronics industry, in the manufacture of shoes and furniture as well as in sports and leisure articles.