Patent ID: 8146193

Claim:
A launcher for tube cleaning projectiles comprising a housing in the form of an elongate cylinder having an internal axial chamber, a portion of the axial chamber defining an air cylinder, a water inlet through the housing, a water plenum formed within the chamber for receiving pressurized water from an external source through the water inlet, a first set of water ports communicating plenum to water inlet, an hydraulic bolt received axially within the internal chamber, the hydraulic bolt being supported for sliding axial movement within the chamber, the bolt having an internal hydraulic chamber and a second set of water ports for admitting pressurized water from the plenum into the hydraulic chamber, the hydraulic bolt having an air piston cooperating with said air cylinder for moving hydraulic bolt from normal position to launch position so that the first set of water ports register with the second set of water ports thereby admitting pressurized water into the hydraulic chamber, and for resetting the hydraulic bolt to normal position, a valve connected to a source of compressed air, the valve having a first position for admitting compressed air to the air piston to move the hydraulic bolt to register first and second sets of ports, the valve having a second position for admitting compressed air to the air piston to reset the hydraulic bolt to normal, and the launcher having means for directing pressurized water from the hydraulic chamber to propel a cleaning projectile through a heat exchanger tube.