Sliding disk valve for pneumatic conveyance of abrasive material

In a linear actuated disk valve for a fluid conveyance system wherein the disk valve has a valve body with an internal chamber and a passage through the valve body, the valve body having opposite ends with external connectors that continue the passage and that are connectable to other components in the fluid conveyance system, a displaceable closure member having a disk retainer assembly with a disk retainer and at least one circular closure disk engageable with the disk retainer, wherein the valve body includes an internal circular lip having a seating surface around the passage, and the disk has a perimeter rim with a seating surface contactable with the seating surface of the lip to seal the passage, the disk being laterally displaced on linear displacement of the disk retainer, wherein the retainer assembly has a connector member constructed to connect with a reciprocal linear displacement actuator that linearly displaces the disk form a closed position with the disk located over the lip of the opening in the valve body and an open position with the disk displaced from the opening in the valve body that opens the passage, and wherein the valve body has a top with a bore and the connector member includes a cylindrical drive shaft that projects through the bore, wherein the improvement comprises:

• a shaft sealing assembly mounted on the valve body around the cylindrical drive shaft, wherein the top of the valve body has a well structure with a series of stacked packing rings contained by the well structure, and a packing bushing with a collar having a series of adjustment screws spaced uniformly around the collar connecting the collar to the top of the valve body, wherein the adjustment screws adjust the pressure of the packing bushing against the stack of packing rings;
• and,
• a seating structure for a linear actuator mechanism, the seating structure being located above the shaft sealing assembly and having a spacer seated on the top of the valve body for supporting the seating structure, the seating structure having adjustment screws for securing the seating structure to the top of the valve body.