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Growing Distinction: LAST-A-FOAM® R-3300 Submersible Foam

When we last featured our LAST-A-FOAM® R-3300 submersible buoyancy foam, we walked through its various applications and key benefits. Now let’s focus on its properties. The series of hydrostatic pressure-resistant, easy-to-machine foam is composed of four products, classified by different densities and depth tolerances. Its unique properties and closed cell structure provide high water resistance and exceptional buoyancy in shallow water and mid-water applications.

Meeting the demand for high-performing, safe and cost-effective buoyancy material, the low density R-3312 was engineered for shallow water applications at depths of up to 300 feet, uncoated. As for the R-3325, its high compressive strength is best suited for use in depths up to 1,200 feet, uncoated. The two engineered densities of submersible polyurethane foam make it a more cost-effective option to syntactic foam, a common yet expensive material used for subsea applications.

When choosing the right buoyancy material for your application, it is important to consider robustness (in terms of strength properties), its machine capabilities, and compatibility with coatings and paints. Hydrostatic testing by the General Plastics method showed low moisture uptake at <5% weight change and little to no volume change measured at <1% volume change for 24-hour submersion at depth. Compared to other materials, General Plastics’ polyurethane-based R-3300 submersible buoyancy foam exhibits a safer failure mode. The coated* R-3325, for example, can withstand depths of over 2,400 feet, where it will slowly compress but will not crush and will still provide buoyancy.

The R-3300 series comes in large blocks as well as custom sizes, and customers also have the added benefit of a full service offering from General Plastics with CNC machining services. The R-3300 buoyancy foam can be machined to exact specifications in our production facility, saving the customer time and money.

At General Plastics, we pride ourselves in our understanding of the market and listening to customers’ needs. The R-3300 submersible buoyancy foam series came from customers’ request for a high-performing and cost-effective material. Do you have underwater applications that could benefit from the LAST-A-FOAM Submersible R-3300? Call us today at 866-825-1378 to learn more about how the R-3300 can be machined to fit your needs or click here to submit your specifications.

*Depth test of the coated R-3300, 25 pcf foam demonstrated a depth tolerance of 2,400 feet. The coating used for this depth test was K5™ Abrasion Resistant Spray Applied Elastomer. Click here to view the K5™ tech data sheet.  Coating was applied by third party.

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