Abstract: A dust and abrasive materials gate valve with an angled valve seat and pivotably mounted valve gate allows for a broad seal area around the periphery of the valve seat, which may be closed tightly by a wedging action due to increasing force applied by the valve actuator. The valve seal is thus not formed along a single, linear surface as in traditional gate valves and the force applied by the valve gate to the seat facilitates closing even if there is wear along the sealing surfaces. Due to the relatively large open area around the periphery of the valve gate just before closing or immediately upon opening, the velocity of particles in pressurized systems is reduced and erosion reduced accordingly.

Abstract: A flap-gate valve having a replaceable wear surface, methods of replacing a wear surface with a replacement wear surface, and methods of retrofitting an existing flap-gate valve with components adapted to work in conjunction with a replaceable wear surface.

Abstract: A flap-gate valve having a replaceable wear surface, methods of replacing a wear surface with a replacement wear surface, and methods of retrofitting an existing flap-gate valve with components adapted to work in conjunction with a replaceable wear surface.

Abstract: An improved mechanical shaft seal to give a tight seal between relatively rotating machine parts and prevent the escape of particulate material into the atmosphere or into the mechanical components of the housing under adverse operating conditions. The seal provides a grease chamber that prevents solid particles from reaching the main seal by migration within the mechanical shaft seal.

Abstract: An improved mechanical shaft seal to give a tight seal between relatively rotating machine parts and prevent the escape of particulate material into the atmosphere or into the mechanical components of the housing under adverse operating conditions. The seal provides a grease chamber that prevents solid particles from reaching the main seal by migration within the mechanical shaft seal.

Abstract: A reduced height dust valve is described which is used in a trap which utilizes a pair of said valves to remove dust from, for example, a vacuum line, is described. The valve includes a body having a longitudinal flow path, a valve seat detachably mounted in the upper portion of the body and opposed flapper plates which seat against each other to close the valve or are rotated downwardly by actuator shafts to open the valve. The flapper plates define adjacent edges which seat against each other by a sliding action permitted by movement of one of the two actuator arms.

Abstract: A dust trap comprising a pair of coaxially mounted dust valves. Each valve has a valve seat and flapper plate and actuator shaft which coacts with the flapper plate to cause it to initially slide and then pivot as the valve opens.

Abstract: An improved gate valve is described. The valve utilizes a flat gate having a beveled edge which slices across a central passage in the valve housing when the valve closes. A manifold is disposed in the passage to direct a purge stream of fluid across the beveled edge as the gate closes. The valve housing consists of upstream and downstream housings which are intended to be bolted together. The adjacent portions of the housings form a first slot in which the gate is slidably received and a second slot downstream of the second slot is formed in the downstream housing. In one embodiment a seat is slidably disposed in the slot which extends laterally across the passage parallel to the gate. In another embodiment the slot extends axially along the passage and the seat is cylindrical slidably retained therein. In the cylindrical seat embodiment the seat is reversible.