|Quoting sweair (Reply 22):|
How does the deck cope with that heat? Its like putting a blow torch to it?!
A couple of inches of steel helps dissipate the heat. Coupled with the standard anti-skid that is already heat-resistant, the deck copes. The matter becomes what happens over the long term, and that's where the Navy is doing experiments on new anti-skid coatings, which are more durable anyways. Current anti-skid coatings may last anywhere from 6 months to 3 years, while some of the new coatings are supposed to last under standard usage scenarios up to a decade or more.
The Navy is doing a lot of experimentation and testing in particular with the Thermion coating, which is a aluminum-ceramic coating process. The coating is 54% aluminum and 46% ceramic powder. This makes the substance extremely light, only 0.5 lb/ft², which exceeds Navy's specifications for type I non-skid. Application process by using a 3/16” diameter twin wire arc-spray.
According to Thermion's commercial documentation, projected life expectancy of the material is 50 years(!). That would literally be for the life of a typical Navy vessel. However, due to the high operational tempo of naval surface vessels and their extreme operating environment, the life expectancy will likely be significantly reduced, but even an 80% reduction would exceed the current life expectancy of the current non-skid deck coatings. However, Thermion’s process has only been used commercially during the past decade. As a result, testing data on the useful life of the product are not available to support the contractor’s claim. The contractor recommends a lifespan of 10 years based on the lack of testing data in a harsh naval environment.
Such aluminum-ceramic coatings would also have a number of side benefits as well; the Thermion coating is much lighter, only 0.5 lb/ft² compared the spec'ed Type 1 coating which weights 0.99 lbs/ft². This provides the potential advantage of reducing topside weight and its effects on a ship’s calculated stability. Furthermore, the Thermion coating has a higher coefficient of friction; 1.1 for Thermion compared to Type 1's 0.95 on a dry surface.
Currently, the Navy applies over 100,000 gallons of organic based non-skid deck coatings per year. The Navy spends about $27 Million per year on non-skid deck coating maintenance for East Coast ships alone. Any savings from applying a more durable coating that lasts longer would be of immense interest with the Navy as a effective cost savings measure, and because of the longer intervals between re-applications, means that instead of having the crew reapply the coating every few years, it can be moved to every time a ship enters a major refit, where they would be stripping the deck anyways, and no one will have to reapply the coating until the next refit.
As a sort of a reference point with the costings, I saw one example of how much it costs. The weather decks of an Arleigh Burke destroyer require 23,000 square feet of surface area to be coated with non-skid. During the current 18-month operational cycle of an Burke destroyer, portions of the weather decks are completely stripped and resurfaced. (It is very rare when all surface areas requiring non-skid get resurfaced all at once). This process can be accomplished one of two ways.
First, the job could be accomplished solely by using ship’s force personnel, for which no cost data exist. Second, the job may be performed during a three-month Ship Refit Availability (SRA) at which point the job can be accomplished by contractors or the Intermediate Maintenance Activity (IMA). The contract price includes a full- application cost of $11 per square foot. This price includes all of the associated material and labour costs to remove existing non-skid and install new non-skid. By comparison, Thermion coating's total cost is estimated to be around $13.50, and it includes all equipment, labour and preparation.
As a result, the per application costings is as follows: for the current standard anti-skid on a Burke destroyer, it would cost around $253,000 per application, and that would last anywhere from 6 months to 2 years. Thermion's per application costs is around $310,500 and that is expected to last 10 years. Over a 10 year time span, the standard anti-skid would cost $1,265,000, compared to Thermion's $310,500, which equals to a almost 77% decrease in costs for anti-skid coatings on board a Burke for 10 years. Expand that out to something as large as an aircraft carrier, which has 196,020 square feet of surface area to be coated with non-skid, the cost savings is enormous. And if Thermion's claims of a 50 year durability life is anyway remotely close to being realistic in a typical Navy use scenario, then the Navy is stupid to NOT be investigating a more durable anti-skid coating.