Castable Shielding

On-site casting is sometimes the only way to achieve the desired shielding. Our castable shielding products can be used to fill walls, surround spent fuel and withstand high temperatures.

SWX-238

Small Mix Kit

SWX-237

Pre-cast

SWX-237 High Temp Boron-Silicone
SWX-237-0 High Temp Poly Substitute (Boron Free)

Boron-Silicone is a fire-resistant, heat-resistant, field-castable elastomer with a high hydrogen content. It is self-extinguishing and will withstand temperatures up to 400° F (205° C) for extended periods while retaining 90% of its hydrogen. Boron-Silicone contains 1% boron for thermal neutron capture and the suppression of capture-gammas.

Other boron concentrations can be supplied upon request.

SWX-237

Pre-cast

SWX-237-0 Poly-Substitute is a boron free version of the standard silicone elastomer mix, boasting the same physical properties, including the high hydrogen content and high temperature specification. It is frequently used when fire and temperature restrictions prevent the use of HDPE.

Although this is a solid material, its resiliency will minimize secondary missile formation due to impacts. Its density is 1.59 g/cc (99 lbs./cu ft).

Boron-Silicone is available in a variety of shapes and sizes. Shieldwerx has provided large pre-cast rings for use as a shield for coolant recalculating lines. The material is also used in the manufacture of large fuel transportation containers.

View Catalogue Sheet 237

View Catalogue Sheet 237-0

SWX-259 and SWX-259Z-4 PolyKast

Polykast is a dry-mix material widely used for casting into closed containers. Polykast is field-castable and provides excellent and cost effective neutron shielding. It has a very high hydrogen content and contains boron to attenuate thermal neutrons thus suppressing radiation from capture-gamma rays. SWX-259 has 0.9% boron, while SWX-259Z-4 contains 4% boron for better thermal neutron attenuation. Polykast has been used in a variety of shielding wall barriers, and transport casts.

No special tools are needed for installation, Polykast only requires mixing with water.

It begins setting up within 30 minutes of casting. This material may be poured in as many layers as required, as each layer bonds readily to the previous one. 56 lbs of dry-mix powder will cast one cubic foot.

The recommended temperature limit for Polykast is 150° F (66° C). When held at this temperature for extended periods, it loses only about 7% of its hydrogen content. Even at 300° F (149° C), it retains 80% of its hydrogen. Polykast is available in fiber drums containing 165 pounds and has a shelf life of 12 months, under dry storage conditions. Other formulas, including SWX-2592-4, are available to vary boron content.

See Catalogue Sheet

SWX-277 and 277Z-5 High Temp Kretekast

High temperature resistance is a frequent requirement for power reactor shielding. Kretekast is a refractory material designed to retain a significant portion of its shielding properties at temperature up to 450°F (230°C). This material will maintain its physical integrity at temperatures up to 1900°F (1038°C). In addition, this rugged material is completely non-combustible and can be easily cast in the field. Its compressive strength is 1000 psi (90 BAR).

Kretekast is well suited to attenuate the neutron flux from power reactors by the inclusion of hydrogen and boron in the forms of temperature-resistant additives. It incorporates approximately three times as much hydrogen as ordinary concrete, making the material far superior for neutron shielding applications.

Standard Kretekast has a boron content of 1.6% and type 277Z-5 contains 5%. It is also available in other concentrations of boron or can be made to be boron-free and used as a poly-substitute.

Type 277 is offered in the form of dry mix for casting in place, including storage casts, but can also be supplied in pre-cast shapes. It is readily shaped with ordinary concrete power tools. Kretekast Dry Mix is available in 300 pound (136kg) drums.

See Catalogue Sheet