Abstract: A locking device for immobilizing trailers to prevent unauthorized movement or theft of the trailer by venting the compressed air that is used to release the brakes. The locking device has a controller unit, a control valve and power source mounted inside a housing. A control mechanism, such as a keypad or key lock system, is located outside of the housing, preferably on a trailer wall. The inlet on the control valve connects to the brake line that delivers compressed air to the trailer's compressed air-operated brakes. In the locked condition, the control valve is set so compressed air vents out the control valve's outlet, preventing release of the brakes. When the proper lock code, key or other signal is received, the control valve closes the outlet to stop the venting and allow the brakes to be released.

Abstract: A locking device for immobilizing trailers to prevent unauthorized movement or theft of the trailer by venting the compressed air that is used to release the brakes. The locking device has a controller unit, a control valve and power source mounted inside a housing. A control mechanism, such as a keypad or key lock system, is located outside of the housing, preferably on a trailer wall. The inlet on the control valve connects to the brake line that delivers compressed air to the trailer's compressed air-operated brakes. In the locked condition, the control valve is set so compressed air vents out the control valve's outlet, preventing release of the brakes. When the proper lock code, key or other signal is received, the control valve closes the outlet to stop the venting and allow the brakes to be released.

Abstract: This disclosure involves a dry heat setting refractory and method of using same in the securing of nozzles to nozzle blocks in steel pour ladles. The refractory is sized so that it can be placed between the nozzle and nozzle block in a dry condition, and then forms an adhesive bond in situ, when molten steel is poured into the ladle and onto the refractory. The composition comprises a sized refractory material, preferably having MgO in the fines fraction, and includes the addition of about 2 to about 6% hydrated alkali silicate, preferably sodium silicate, which forms a refractory bond when engaged by the hot metal.

Abstract: This disclosure involves a dry heat setting refractory and method of using same in the securing of nozzles to nozzle blocks in steel pour ladles. The refractory is sized so that it can be placed between the nozzle and nozzle block in a dry condition, and then forms an adhesive bond in situ, when molten steel is poured into the ladle and onto the refractory. The composition comprises a sized refractory material, preferably having MgO in the fines fraction, and includes the addition of about 2 to about 6% hydrated alkali silicate, preferably sodium silicate, which forms a refractory bond when engaged by the hot metal.

Abstract: This disclosure concerns a thermo-chemical bonded refractory product which comprises inactive refractory grains bonded together by mullite. The refractory is emplaced in a furnace or other pyro-processing unit by pressing, ramming, gunning, casting, etc. The refractory product is made by mixing inactive refractory grains with a mixture of zircon and alumina powders and a small amount of an alkaline earth oxide catalyst. The catalyst breaks the zircon down into ZrO.sub.2 and SiO.sub.2 at relatively low temperatures. The SiO.sub.2 thus liberated is unusually reactive and reacts with the alumina to form mullite and the ZrO.sub.2 adsorbs the alkaline earth oxide.