Abstract: An apparatus for braking comprises a fluid operated parking brake piston connected to a pressure plate with an axially extending portion and a radially extending portion. The radially extending portion is contacted on one side by at least one spring and is in selective contact with a brake pack on the other side. A method for braking comprises biasing the pressure plate into an axial direction when the pressurized fluid behind the parking brake piston is overcome by the at least one spring. The radial portion of the pressure plate is urged into the brake pack thus slowing the rotation of the rotors relative to the stators in the brake pack.

Abstract: Method and apparatus for treating gases by passing said gases horizontally through a plurality of spray zones wherein the gases are contacted in each spray zone with scrubbing medium in a plurality of vertically disposed bays; utilizing a scrubbing medium of varied concentration or chemical reactivity between the adjacent spray zones and bays; combining and reamalgamating the spray medium and re-spraying said amalgamated medium in one or more spray zones and bays.

Abstract: An apparatus and method for monitoring electrode rapper operation in an electrostatic precipitator. The actual movement or impact of the hammer in an electrode rapper is sensed and a control signal is generated and transmitted to a monitor in response thereto in order to produce an immediate and accurate indication of rapper failure.

Abstract: A gas conditioning means and more particularly a gas conditioning means incorporating an improved method of providing sulfur trioxide for injection into a flue gas stream.

Abstract: A gas cleansing apparatus and more particularly an electrostatic precipitating apparatus having improved discharge electrode means therein.