Itis no tiny wonder that railcars are regions where corrosion occurs on a standard basis. They can be typically used to ship large, heavy commodities and are subject to a best deal of abuse during the loading and unloading process. Sum to that the exposure to harsh and wildly variable weather conditions and you have knowledge of atom structure for initiating and fostering corrosion. According to Cliff Haskins, Vice President of Marketing for SPI, the railroad sector is always receiving note of for ways to manage the damaging effects of corrosion. Despite the dramatic improvements in train engines and railcars since their invention within the 1800's, corrosion and contamination manage remain difficult problems to mitigate.
This$50 billion a year sector has a huge incentive to protect the assets that haul freight all throughout the United States, says Haskins. If corrosion manage is problematic in railcars transporting typical cargo, for example steel, lumber or grain, imagine the repercussions if corrosion is not mitigated in railcars carrying low-level radioactive material. There is a best deal at stake in this situation: a coating system should be applied to these railcars that shall protect the cars from corrosion and be the final line of defense sequential to protect the environment and the general public from any accidental contamination. SPI's Polyshield HT was the high performance polyurea coating system chosen for this important job. This project presented multiple unique challenges and compulsory higher than your average protective coating.
Polyshield HT polyurea was specifically formulated to release the greatest of most worlds, combining high tensile strength, abrasionresistance, and good elongation properties. The fact that the Polyshield HT is a monolithic coating and has no seams helps greatly to reduce the possibility of a corrosion cell. This gave our client, in this case the USA Department of Life D. , an extremely tough and durable protective coating solution, with ample flexibility to withstand drastic annual weather cycles, says Dan Helton, President and Founder of SPI. In addition, with correct surface preparation, the Polyshield HT coating with AE-4, an adhesion enhancer, shall be applied directly to the steel substrate without first applying a primer.
The AE-4admixture dramatically increases the coating adhesion to the steel or metal substrate. This was extremely beneficial on this fast-track project, saving most time and money. ALL ABOARDThe USA Department of Life commissioned SPI to apply Polyshield HT polyurea to the interior of 35 railcars in Cincinnati, Ohio. As an aside, consequently the D. was the entity responsible for transporting the low-level radioactive fabric through the USA, they were not the owners regarding the railcars.
Regarding to Charley Hancock, of AIC Foam and Coating, It is common for businesses or wealthy private individuals to purchase railcars, customize them for the intended end-use, and then rent or lease them out. Within the case of this critical project, the railcars were leased to the D. Sequential to obtain an accurate picture regarding the scope regarding the project, it is important to understand the players and the payload involved. Paul Hall, regarding the Ohio Field Office regarding the D. , was the project manager on the job.
Dick Hugo, of Applied Surface Technology, served as the general contractor on the project. SPI supplied the polyurea protective coating system. Hancock was the certified technical representative on the job. He was recommended for the project by SPI. Charley has an great reputation for his quality of work, mostly for difficult, high-profile jobs, says Haskins.
Hancock was responsible for training the applicators from Gunderson Midwest on application methods and technique for spraying Polyshield HT. The Gunderson Midwest team consisted of 3 men, Rick Roth and Robert Pendleton. The most intriguing component of this project is, of course, the payload that the railcars should ultimately be transporting throughout the country. Regarding to Hancock, the freight consisted of low-level radiological waste that contained alpha or beta particles. The radiological waste was stored in extremely tough and virtually indestructible metal radioactive containers.
These metal containers were drafted to remain intact and sealed even within the function of a collision with another train or vehicle. The polyurea was used like a secondary containment liner system to prevent any unlikely spillage or environmental contamination and to protect the steel railcars from abrasion and impact damage from loading and transportation, says Hancock. He adds that subsequent to each shipment, to help protect the environment and make sure that no post-shipment contamination, each railcar was force washed and cleaned. All regarding the h2o from the cleaning process was saved and analyzed to make sure the h2o did not contain any alpha or beta particles. FULL STEAM AHEADThe unusual payload notwithstanding, this job had a best deal of challenge.
The two-man crew only had 28 days at the repair facility to done the surface preparation and coating application on the steel interior of 35 railcars, each one measuring approximately 40' 12. 19m in length and 8' 2. To make the deadline even more imposing, the train yard had strict restrictions related to the timeframe within which the crew should prep and spray the railcars. It was imperative for the crew to hold a strategy in location for the preparation and application process, considering there was no room for error with such a brief timeline. Regarding to Hancock, the railcars were brought into a repair facility that had multiple buildings interconnected by an elaborate track system with roundhouse tables, allowing for the cars to be moved with no problems from building to building.
The region was divided into a prep region and spray area. The railcars were first brought into the sandblasting booth region to have all debris and rust removed from the steel substrate. 08mm anchor profile was created together with the blast press to make sure that a correct surface for spraying the polyurea directly onto the steel. The cars were then moved into the spray area, which was contained to prevent overspray onto any other railcars or structures within the vicinity. Once the cars were within the spray area, they were ready for the polyurea application.
Polyshield HT is a plural component, pure polyurea elastomer. It is a 100% solids coating and contains no solvents or volatile organic compounds VOCs. It is an aromatic polyurea, which means that it is susceptible to color change when exposed to ultraviolet UV rays. For this critical job, the formulation of Polyshield HT was a terra cotta color with high pigment loading and contained a UV enhancer to reduce color fading. The crew applied the coating with a Gusmer 20 or 35 proportioner at a thickness of 60 to 80 mils 1.
The coating was a thorough choice. It should be quickly and with no problems applied within the train yard together with the plural component equipment. We bought the machinery directly from SPI. It helped possessing a one stop source for the fabric and equipment, says Hugo. It shall also be important to note that during the application regarding the coating, the crew was outfitted with full face masks with new space respirator systems, Tyvek suits, and gloves.
All appropriate well-being precautions were followed throughout each step regarding the project. ON THE RIGHT TRACKThe process had to work like clockwork sequential to make sure that that the cars should immediately be on their method to pick up the radioactive material. Regarding to Hugo, To meet the deadline we literally had to line up the cars and beginning spraying. This quick turnaround was likely due to the fact that of Polyshield HT's rapid curing properties. Downtime was minimized and the railcars were quickly returned to service.
In addition, Mother Nature cooperated for the duration regarding the project and there were no delays due to inclement weather. Consequently velocity was imperative in every other aspect regarding the job, a slower than average gel time helped make the Polyshield HT polyurea the right decision for the project. Polyureas are typically known for their fast gel time, in some instances as little as 5 seconds. This helps prevent any ambient or surface moisture from affecting the material. When polyurea gels this quickly, the coating tends for shape a bumpy, or orange peel surface.
However, polyurea shall be engineered to gel more slowly, creating a smooth surface and enhancing adhesion. On this job, great adhesion regarding the coating system was an absolute must. Pinholes and flaws within the coating system should not be tolerated: the coating system was subsequent to all the secondary containment for the radioactive material. Any imperfections or vacations within the coating should lead to a coating system failure and the likely release of low-level radioactive fabrics into the environment. The coating system was literally place to the test during the final inspection regarding the project.
The Polyshield HT exceeded the 1,750 psi pull-off test requirement. The coating system passed the test, and no defects were located in any regarding the railcars. Over time, the coating was exposed to extreme heat, freezing temperatures, and the constant loading and unloading regarding the canisters of radioactive material. Regarding to Hall, the Polyshield HT coating system has had an exemplary track record out within the field. We are very impressed with how well the [coating] is holding up over time.
It adhered very well and it is meeting our project's intended use, says Hall. In other words, the coating system lived up to the expectations of great abrasion resistance and the ability to withstand a broad section of weather conditions. Hall shall also be impressed together with the ease with which the coating system shall be repaired within the field if needed. We maintain an aggressive inspection and repair program for the interior of all of our railcars since huge chunks of debris for example concrete or metal can damage the integrity of a lining. The SPI product was successfully patched within the filed by our project personnel creating use of the patch kit materials, says Hall.
A coating system is only as good as the crew who applied it, and Hancock and SPI are quick to credit the Gunderson Midwest team, as well as the product for the success of this project. Regarding to Haskins, subsequent testing of a cross section regarding the final product proved superior spray application as these test conclusions exceeded the SPI published physical standards. The project was a true success thanks to the diligence regarding the Gunderson West application team. They went the extra mile and delivered an great coating solution below a tight deadline, adds Hancock.
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