X-Scan: Giving Transportation Departments “X-ray vision”
The Write Brothers had a bicycle shop. LPPFusion has X-Scan technology patented and ready for the engineering phase. X-Scan technology is portable, economical, extremely intense hard X-ray source off spin of a dense plasma focus (DPF) device. Such a source, transportable by truck, will allow economical non-destructive inspection of the nation’s critical infrastructure, leading to savings in repair costs of at least five billion dollars annually. In February 2011, LPPFusion achieved a major milestone by measuring sufficient X-ray energy to show that our X-Scan product is technically feasible. This technology is ready for mass production and we are currently looking to sell out to the highest bidder.
Contact us at firstname.lastname@example.org, or at Home Office 908-546-7654 to find out how to take over this patented technology.
X-Scan’s photon energy and power adjustability will allow the use of Compton scattering, in which the X-rays are scattered off the material being probed and returned to a detector on the same side of the object as the source of energy. Compton scattering requires far higher X-ray power than direct X-ray scanning, in which the detector is on the opposite side of the structure from the source. This means X-Scan can scan roads, bridges and buildings all on the one same side. Such one-sided X-Scans will greatly reduce the preventive maintenance and infrastructure inspections costs and times.
The X-ray source technology is being developed as a “spin-off” of our medium–term research into the use of the DPF as a source for fusion energy. Essentially the same technology can produce both useful energy and extremely intense X-ray pulses.
Our market projections, based on discussions with likely final customers including state departments of transportation, indicate that our X-ray source integrated into an inspection system can yield sales of $20 million/year and profits of at least $3 million/year within two or three years of introduction into the market. We anticipate that we will be able to begin marketing this device in three to four years with the help of likely government funding.
What experts have said about LPP’s “X-ray vision” inspection system:
“Technically the plan is very strong. The objective is truly revolutionary, yet the plan to achieve it is feasible. The steps to the objective are clearly defined. The plan is based on new, highly original theory and analysis. There is a good coordination of simulation and experimentation. The optimization plan, while ambitious, is feasible.” – Technical review of LPP’s grant proposal by reviewers at National Institutes of Standards and Technology, Advanced Technology Program, U.S. Dept. of Commerce.
What a potential customer has said about the product we are developing
“We believe that your proposed device, a high powered X-ray source with imaging and source located on the same side of the structure, offers benefits to end users such as the Florida Department of Transportation. We believe such a device could potentially allow more accurate and thorough inspection of our bridge structures. In particular we see the possibility of being able to inspect for post-tensioning corrosion and voided ducts, items that are difficult to locate by non-destructive methods. If and when this device is available, we would be interested in a demonstration of its capabilities” – Marcus. H. Ansley, Florida Dept. of Transportation.
Our immediate goal in this project is the development of a truck-portable x-ray source that will emit 100 J of X-ray energy at average photon energies above 100 keV. We anticipate pulse durations of the order of 4-8 ns and source size approximately 20 by 80 microns or smaller. Pulse repetition rates will be basically limited by the power source but will be in excess of one per second.
We have already demonstrated in laboratory experiments the achievement of our goal for an x-ray source. We generated over 100 J of x-ray energy with an average photon energy above 1 Mev. This radiation was detected through a 6” thick shield of copper and steel and generated a signal-to-noise ratio of over 1,000. The pulse duration was 4 ns. While the source size was somewhat larger than our goal, with 200 microns radius, we anticipate source size will be decreased in very near-term experiments. The experimental device used to generate this weights 3 tons including all equipment and so could be modified to fit in many trucks. We consider the research on this source to be complete, although engineering development into a product is still required.
This source will be integrated into an inspection device that will be able to scan roads, bridges and buildings with source and detector both located within the truck (or on a gantry). The X-ray source will repeatedly pulse as the truck moves, emitting sheets of X-rays collimated by lead shields.
X-rays scattered from the structure will then be imaged using a pinhole or other imaging method. This instrument will be capable of scans with resolution of 2 mm up to 32 cm (1 foot) into concrete and up to 8 cm (3.2 inches) into steel. This is sufficiently capable for one-sided scanning of roadways, bridge structures, reinforced concrete girders and other large infrastructure components. The outer 10-30 cm of structural elements is the portion that is most important to inspect since corrosion and other fault processes occur from the outside inward.
We also intend to integrate the same X-ray source into other types of instruments. One major area of application is high resolution inspection of thick manufactured parts. The DPF X-ray source used as a direct, rather than scattering, source will achieve 20 micron resolution in steel parts as much as 16 cm thick. Such high resolution reveals micro-cracks that are important for high stress parts such as pressure vessels.
Another major application area is as an economical source of high intensity X-rays for high speed laboratory diagnostics. While laser-based X-ray sources exist with pulse durations as short as femtoseconds, existing sources have emission energies in the range of nano J. In contrast X- Scan pulses will produce 30-100 J. The combination of high pulse energy with high photon energy and ns-pulse duration makes possible studies of fast processes occurring in dense matter, such as explosion dynamics.
In addition, the high flux will make possible high space and time resolution of fast plasma phenomenon. At the low end of the X-ray energy range, a DPF X-ray source at a distance of one meter will provide 10,000 photons per square micron. With a source size of 20 microns along the axis, resolution of a few tens of microns of fast phenomenon will be achievable.
Market for the product
Currently more that $30 billion a year in the United States is devoted to repair of roads and bridges. A large fraction, probably the majority, of these repairs are not preventative maintenance, but are made after obvious failure has occurred (cracking of road surfaces, visible corrosion of bridge structures, etc.). These obvious failures occur long after, generally years after, the first corrosion-based voids and cracks occur hidden within the structures.
Post-failure repairs are estimated to be more than ten times as costly as pre-failure repairs. If incipient, hidden corrosion is detected in time, repair of the affected parts (sealing of cracks, re- welding, re-leveling of roads) is far less expensive. For example, bridge surface patching and repair (preventative maintenance) are estimated to cost around $0.50 per square yard. In contrast, bridged deck overlay and joint replacement, occurring after major cracking of the surface, costs about $90 per square yard. Bridge deck replacement costs about $360-400 per square yard. Even taking into account that preventive maintenance has to be performed about ten times as often as rehabilitative maintenance, preventative maintenance still costs only about 5% per annum as much as rehabilitative maintenance, let alone complete replacement.
Based on a detailed analysis of bridge and runway maintenance, LPP has calculated that a mid-range estimate on savings would be around $8 billion per year in preventative maintenance of structures before they actually fail. Our X-Scan device will make such savings possible. As a result, we think that state departments of transportation will be extremely interested in our device, as is already evidenced by letters of interest from the DOTs of several states.
To estimate the size of this new market, we have to first calculate the need for inspections. Annual inspections of roads and bridges are essential since corrosion processes are seasonal and advance during every winter and spring. We have to estimate the amount of inspection that can be performed annually by each truck-mounted DPFX. With several-times-per-second pulses, cross sections every 2 meters can be obtained with a 10 m/s (22 mph) scanning rate. In some roads, a faster rate will be allowable and on bridges a much slower rate will be needed, but this is a good order-of-magnitude estimate. Realistically, taking into account time to get to and from the areas being scanned and unavoidable interruptions, approximately 3 hours of scanning per working day or 750 hours per year per unit is reasonable. This means 17,000 miles of bridge and roadways can be scanned by each unit per year (single lane).
There are 3.9 million miles of roadway in the US, including all bridges. With an average of 4 lanes per roadway, this amounts to an annual need for 15.6 million miles of single-lane scans. For this, some 900 X-Scan machines should be adequate. Pipeline inspection could expand this total considerably, but will not change the order of magnitude of the domestic market. As we expand to global markets, sales could eventually increase to double this number.
Given this potential market, we anticipate reaching a sales rate of about 200 units per year within two to three years after introduction into the market. We anticipate that sales for NDI manufacturing units and laboratory devices will be considerably less, but may collectively increase sales figures by 25%. With a price of $100,000 per unit, this will mean sales in the range of $20 million a year.
There are currently three main competing methods of non-destructive inspection (NDI) for infrastructure:
— Gamma rays from cobalt-60 sources
— Hard X-rays generated by linear accelerators (linacs)
All have been well understood for years. However, all have serious drawbacks that prevent them from being very effective, and except for cobalt-60, from entering into widespread use.
Gamma rays. Scanning with cobalt-60 sources, which emit gamma rays at 11 and 13 MeV, is the most common method of infrastructural inspection, and there are many suppliers for the cobalt-60 sources. Sources are placed on one side of the structure to be inspected, with a film or other detector on the other side. The main advantage of the approach is that it is cheap, requiring only the purchase of radioactive material and a detector (or just film). In addition, the gamma rays are highly penetrating. However, the sources are quite weak, producing typically 6×1010 photons per second. This limits achievable resolution. As a result, incipient cracks and voids can be missed.
The most important disadvantage of cobalt-60 sources is that they require the detector or film to be placed on the opposite side of the structure to be scanned. For above-ground pipes, this is not much of a problem, but for buried lines and bridges, positioning the detectors can be difficult or impossible. Roadway scanning is impossible.
X-rays from linacs. The principal alternative method to cobalt-60 for producing penetrating radiation for non-destructive testing and inspection employs a linear accelerator to produce an electron beam. The beam, colliding with a solid target, then generates the X-rays. Varian Corp. is a leading producer of such devices, whose main use is for medical radiation treatment. Individual machines produce hard X-rays ranging in energy from 1-15 MeV. Pulses, lasting approximately a microsecond, are generated at a 300 Hz rate. Devices sell for $400,000 and up.
Linacs used for infrastructure inspection share the same drawback as cobalt-60 in that they require the source and detectors to be on opposite sides of the object being inspected. In addition, linac-based devices are too expensive for most end users. As a result, Varian reports that only about 150 of the devices are in use worldwide, and most of these are used by US Dept. of Defense for inspection of tanks and other armored vehicles, not infrastructure. On the other hand, linacs have the significant advantage over cobalt-60 that they produce far more photons per second, approximately 5,000 times more. This increases resolution, which can approach a couple of mm.
Radar. In this method, used for road inspection, radar signals are reflected off of sub-surface layers, and the return signal is analyzed to detect road layer thickness. A number of small companies, such as Geophysical Survey Systems, Inc. supply truck-mounted systems for highway inspection. Radar does not penetrate steel, so cannot be used for inspection of metal structures such as bridges and pipelines. However, for roadway inspection, radar has significant advantages. It is very fast, with scans being produced at highway speeds. In addition, of course, detector and source are on the same side of the object being scanned. The main disadvantage of the radar system for road inspection is that the return signals are difficult to interpret. Highway departments that have tested such systems in an effort to detect roadway separation and surface voids have found that many conditions, such as changes in material composition, or just minor dampness, change the reflection of signals, and interpretation requires a high level of skill and long training. As a result, only a few dozen of these inspection systems are in use.
In addition, radar does not provide high resolution, with typical resolutions being 3 cm.
Incipient faults can thus be overlooked when they are easiest to fix.
X-Scan advantages. The X-Scan hard X-ray source overcomes the limitations of competing techniques due to its power, adjustability and low cost. At its intended output of 100 J at 300 keV photon energy, the source will have sufficient capability to scan deeply into structures using Compton backscattering. The return signal is backscattered, so that both detector and source are on the same side of the structure. This overcomes the principle limitation of both cobalt-60 and linacs. X-Scan has sufficient power for one-sided scanning of roadways, bridge structures, reinforced concrete girders and other large infrastructure components. In contrast, existing portable X-ray sources simply have too few photons per pulse for such a technique. Even if longer exposures are made, with multiple pulses, backscattered radiation falls below background levels with conventional sources and is not observable. But the powerful and fast DPF pulses far exceed background levels. The high per-pulse energy of the DPF source will generate 10,000 times more photons per pulse than conventional linac sources. With far shorter pulses than linacs, there will be ten million more photons per unit time.
X-Scan will have less energy per photon than linacs, and thus each photon will have only a third the penetrating power of linac-generated photons. However, the far greater number of the X-Scan photons completely overwhelms this difference. The net result is that X-Scan has enough photons returned from a scanned object to use Compton scattering, while linacs do not.
Unlike radar, which cannot penetrate metal, the hard X-rays our source will produce can scan through concrete and metal. In addition, the scans produced will be very straightforward to interpret, in sharp contrast to the difficulty in interpreting radar signals. Since voids created by corrosion, cracking or layer separation will backscatter essentially no X-rays, such voids will show up clearly as shadows in the final image. X-Scan, with 2mm resolution, matches the resolution of linacs and far exceeds that of cobalt-60 or radar.
Using our unique and adjustable approach, the DPF source will be able to scan an object with different energy X-rays, ranging down to as low as 30 keV, which will allow more depth information and detailed scans of near-surface features. Adjustability of the photon energy is extremely useful for inspection of structures, since it allows the inspector to focus in on small surface features once deep corrosion has been detected with higher energy. It also allows the user to select the energy appropriate for the structural part being inspected–higher energy for large parts, lower for smaller ones, maximizing resolution at each step. Linacs cannot produce the adjustable output of X-Scan. Equally important, the DPF X-ray source will make possible a more economical NDI device, reducing costs and allowing agencies responsible for infrastructure inspection to purchase them. Interviews with highway inspection managers indicate that prices at around $100,000 per unit would be acceptable, in contrast to the much higher linac prices of $400,000, which are unaffordable.
Development and Marketing Plan Current Phase:
When LPP applied for a $2 million Advanced Technology Program (ATP) grant from NIST in 2004, our proposal for developing the plasma focus device as a powerful source of X-rays was accepted by ATP at the first “gate” as having “high technical merit”. Dr. Burabi Mazumdar, a NIST physicist, told LPP that “there were no negative comments” on the technical review, which was a real vote of confidence in LPP’s scientific plans.
Phase 1: Initial development
As our current experiments towards Focus Fusion yield data, we will search for the ideal parameters for generating X-rays in addition to suppressing them. With the knowledge of these parameters, we will be able to begin experiments aimed at optimizing X-Scan. We have already achieved the basic x-ray output required, but will learn more about how to fine tune the output.
Phase 2: Development of complete inspection product
Once prototype development of the X-Scan source is complete, we will work with a commercial partner to integrate the source into a complete inspection system with appropriate detectors and an imaging system. This partner will commit to work with us in the event our prototype-source development (Phase 1) is successful and will purchase an “option to invest” from us. The partner will either be a company that specializes in detectors and NDI products or a company with substantial resources that wishes to enter this market. We will support this partner as an R&D provider as well as licensor, helping them to refine the Compton scattering technique for use with their detectors. We do not foresee significant technical challenges here. In addition to up-front capital commitments by our partners, and a possible exchange of equity interests, we foresee royalties or other sharing in revenues.
LPP will also select a manufacturing partner to assemble the devices. Three main components of DPF devices (the capacitor banks, the switching system including switches, triggers and power supply, and the vacuum pumps) are all items that are manufactured on a small scale by well-established firms, such as General Atomics for the capacitors and R. E. Beverly for the switches. The only unique components for the DPF are the electrodes themselves, which are quite inexpensive after the initial design expense is recouped. Thus all components of the device will be either off-the-shelf or will be produced with mature and economical techniques. This will make manufacture of X-Scan economical from the start. This manufacture mainly involves assembling the components, which will be done on a contract basis. LPP will not become a manufacturer of final X-Scan systems itself. We estimate that no more than about $4 million per year will be needed to move from the end of the Phase 1 experiments to a product prototype. Additional money will be required for a marketing campaign. This figure is relatively modest because of the relatively small number of customers (state departments of transportation, large oil companies, etc.) that will have to be contacted. Our plan is to raise this money from two main sources. First we will be expecting any prospective manufacturing partner to invest some of their own capital in this project as their “buy-in”. This will be the main source of funding. Second, once the technology is proven through the Phase 1 project, we anticipate that it will be much easier to raise substantial sums of money privately through the sale of LPP stock in private placements.
Phase 3: Marketing and licensing of final product
Once we have entered our primary market and established a secure presence there, we may also license the technology to other manufactures with whom we do not expect to compete, for example in various foreign markets where we would have trouble establishing the necessary relationships with local customers. Historically, small companies that enter foreign markets with local partners fare better. In addition to geographic licensing, we anticipate executing vertical applications licenses to companies in fields apart from our core focus of non-destructive inspection.