| 摘要 |
A pressure sealing assembly for a swing tube-type concrete pump. The assembly provides a fluid-tight seal between the intake end of the swing tube and the ports of the pumping cylinders. Pressure faces are formed in the bearing assembly where the discharge end of the swing tube passes out of the concrete hopper, and a lubricating medium, such as grease, is positioned in this assembly adjacent the pressure face which is directed toward the intake end of the swing tube. Pressure is selectively supplied to the lubricating medium in the bearing assembly, so that this pressure applies the force toward the intake end of the swing tube, which forces the intake end of the swing tube into sealing abutment with a cylinder port. The grease pressure is supplied to the assembly by a hydraulic ram assembly, this receiving hydraulic pressure from the same source which operates the pumping cylinders of the pump, so that the application of pressure to the bearing assembly is timed in sequence with the pumping action of the cylinders.
|
