Abstract: A rod scraper for hydraulic cylinders and the like is disclosed which includes an elastomeric ring member having an inner surface defining a central aperture adapted for receiving a rod for axial movement relative thereto, the inner surface including a scraper portion having an inner most circumferential lip positioned adjacent one end of the elastomeric seal member for scraping the rod, the elastomeric ring member further having a curved outer surface portion generally axially coextensive with the scraper portion, and a metallic backing ring affixed in overlaying relation to at least a substantial portion of the curved outer surface portion of the elastomeric ring member, the backing ring being resiliently biased against the curved outer surface portion to urge the lip of the elastomeric ring member against the rod and sufficiently flexible to allow some radial movement of the rod while maintaining the lip in circumferential contact with the rod.

Abstract: An improved pop-up irrigation sprinkler with integral flow control valve, and an improved separate flow control valve, defined by a dual flowpath for pilot flow within the flow control valve; a stem-flushing feature using an interrupter disc (54) mounted on a piston (48), providing a flowpath for a brief hydraulic flushing cycle after a momentary interruption of flow; a direct acting hydraulic pilot valve (92) to permit hydraulic control of an electric type sprinkler or a separate flow control valve; an improvement of the bearing guide (80) by the addition of a resilient barrier seal (84) to prevent seizing of the stem to the bearing guide when fully extended, the seal maintaining a close fit to the stem and yet being sufficiently resilient to permit the flushing of the stem; and a variable orifice in the inlet to the bonnet chamber to retard the initial opening rate of the valve.

Abstract: A seal for a regenerative air preheater. The seal is comprised of two members that each have a plurality of tabs and slots. The tabs and slots interlock so that the tabs on one member are positioned adjacent the slots on the other member. Further, the tabs have a narrow neck section and a wider sealing section. The wider sealing sections overlay and the narrow neck sections are positioned within a recessed region of the notch on the opposite member so as to interlock the two members. Preferably, the neck sections do not significantly overlap thereby providing greater flexibility for each of the tabs. The seal is mounted either to the rotor or to the inner wall of the housing so as to extend through the bypass gap between the rotor and the inner wall of the housing. As the tabs are flexible, the tabs can resiliently deform as a result of the tabs making contact with the sealing surface of the heat exchanger.