Abstract: A failure tolerant tire inflation system for supplying pressurized air from an onboard source to the vehicle tires in the event of a pressure drop in one or more of the tires below a predetermined level. The system includes a tire inflation valve communicable with the source of pressurized air, a tire selector valve assembly for selectively communicating air from the tire inflation valve with the vehicle tires, a plurality of valve assemblies each communicating with at least one tire and selectively communicating with the tire selector valve assembly. A controller selectively activates and deactivates the tire inflation valve and valve assemblies to sequentially check the pressure in the tires and direct air to any underinflated tire. A transducer is provided for detecting the tire pressure levels upon the opening of the valve assembly communicating with that tire and communicating the underinflated condition to the controller.

Abstract: A failure tolerant tire inflation system for supplying pressurized air from an onboard source to the vehicle tires in the event of a pressure drop in one or more of the tires below a predetermined level. The system includes a tire inflation valve communicable with the source of pressurized air, a tire selector valve assembly for selectively communicating air from the tire inflation valve with the vehicle tires, a plurality of valve assemblies each communicating with at least one tire and selectively communicating with the tire selector valve assembly. A controller selectively activates and deactivates the tire inflation valve and valve assemblies to sequentially check the pressure in the tires and direct air to any underinflated tire. A transducer is provided for detecting the tire pressure levels upon the opening of the valve assembly communicating with that tire and communicating the underinflated condition to the controller.

Abstract: A system and method for mixing cement slurries at an oil or gas well site and for pumping such slurries into the well provide automatic combined and interrelated density and pumping control and selectable sequential control of predetermined mixing and pumping stages. Specific conditions automatically controlled include water rate, water pressure, slurry density, recirculating slurry pressure and downhole pump rate. Each of these conditions is the subject of a respective control loop that operates independently, but under control from a central controller. The central controller generates interrelated inlet water, inlet dry cement and outlet downhole pumping control signals responsive to operated-entered desired operating characteristics.