Sealing arrangement for adjustable elements of a pump

A throatbush device for use in a centrifugal pump having a pump element portion and a side liner portion that defines a suction plate of a the centrifugal pump, comprising:

• a throatbush having an axially-extending tubular portion and a radially-extending ring portion, the radially-extending ring portion having an outer circumferential area with an annular surface;
• a seal located along the annular surface of the outer circumferential area of said throatbush, the seal comprising,
• an annular band having a first circumferential end and a second circumferential end,
• a first surface extending at least partially between said first circumferential end and said second circumferential end,
• a second surface extending at least partially between said first circumferential end and said second circumferential end, the second surface being positioned along said annular surface of the outer circumferential area of the throatbush, and
• a resilient annular flange positioned proximate said second circumferential end of said annular band, said resilient annular flange having a pivotable region that extends from said first surface of said annular band radially beyond a plane defined by said first surface of said annular band in a direction radially away from said second surface of said annular band, said resilient annular flange having a surface oriented toward the first surface of said annular band and being arranged so that, in use, a slidable portion of the surface of said annular flange is in slidable direct contact with said first surface of said annular band, said slidable portion being adapted to be slidable along said first surface toward or beyond said second circumferential end as the pump casing elements are adjusted relative to each other.

A centrifugal pump, comprising:

• an outer pump casing defining a volute;
• a main liner positioned along an inner surface of the volute of the outer pump casing;
• a suction plate connected to said outer casing and positioned adjacent a portion of the main liner, the suction plate having a central opening defining a suction inlet opening;
• an axially-movable throatbush having an axially-extending tubular portion, that extends through the suction inlet opening of the suction plate, and a radially-extending ring portion that is positioned adjacent the suction plate, the radially-extending ring portion having an outer circumferential area with an annular surface;
• a seal located along the annular surface of the outer circumferential area of said throatbush, the seal comprising,
• an annular band having a first circumferential end and a second circumferential end,
• a first surface extending at least partially between said first circumferential end and said second circumferential end,
• a second surface extending at least partially between said first circumferential end and said second circumferential end, the second surface being positioned along said annular surface of the throatbush, and
• a resilient annular flange positioned proximate said second circumferential end of said annular band, said resilient annular flange having a pivotable region that extends from said first surface of said annular band radially beyond a plane that is defined by said first surface of said annular band, in a direction radially away from said second surface of said annular band;
• wherein the resilient annular flange of the seal is positioned, along two extending faces of the resilient annular flange, against the suction plate, and wherein the resilient annular flange is clamped between the suction plate and the main liner so that the resilient annular flange, at initial assembly of the centrifugal pump, is positioned against and in direct contact with said first surface of said annular band of said seal.

A method of sealing an adjustable throatbush of a centrifugal pump relative to other pump elements of the centrifugal pump, comprising:

• providing a centrifugal pump having an outer casing, a main liner positioned along a volute of the outer casing and a suction plate having a central inlet opening;
• providing an axially-movable throatbush having an axially-extending tubular portion, that extends through the suction inlet opening of the suction plate of the pump, and a radially-extending ring portion that is positioned adjacent the suction plate, the radially-extending ring portion having an outer circumferential area with an annular surface;
• providing a seal located along the annular surface of the outer circumferential area of the axially-movable throatbush, the seal comprising,
• an annular band having a first circumferential end and a second circumferential end,
• a first surface extending at least partially between said first circumferential end and said second circumferential end,
• a second surface extending at least partially between said first circumferential end and said second circumferential end, the second surface being positioned along said annular surface of the axially-movable throatbush, and
• a resilient annular flange positioned proximate said second circumferential end of said annular band, said resilient annular flange having a pivotable region that extends from said first surface of said annular band radially beyond a plane that is defined by said first surface of said annular band, in a direction radially away from said second surface of said annular band;
• positioning the resilient annular flange of the seal to contact the suction plate of the pump along two extending faces of the resilient annular flange;
• and
• clamping a portion of the resilient annular flange between the suction plate and the main liner of the pump such that, at initial assembly of the centrifugal pump, a portion of the resilient annular flange is positioned against and in direct contact with the first surface of the annular band of the seal and is configured to move along the first surface of the annular band in slidable direct contact therewith as the axially-movable throatbush is axially adjusted.