Abstract: A pump housing device for a fluid pump comprises a rear wall element comprising a rear surface turned towards an impeller. The rear wall element comprises an opening defining a cylindrical surface along a longitudinal central axis. The opening receives a rotating drive shaft of the impeller. A static seal element has a plane seal surface that seals against a plane seal surface of a rotary seal element mounted to the drive shaft and rotating with the drive shaft. The plane seal surface of the static seal element is turned away from the rear surface. One or more grooves extend through the rear wall element and through the rear surface and the cylindrical surface. Each groove has a bottom line that extends from the rear surface to the cylindrical surface.

Abstract: A pump housing device for a fluid pump comprises a rear wall element comprising a rear surface turned towards an impeller. The rear wall element comprises an opening defining a cylindrical surface along a longitudinal central axis. The opening receives a rotating drive shaft of the impeller. A static seal element has a plane seal surface that seals against a plane seal surface of a rotary seal element mounted to the drive shaft and rotating with the drive shaft. The plane seal surface of the static seal element is turned away from the rear surface. One or more grooves extend through the rear wall element and through the rear surface and the cylindrical surface.

Abstract: A self-priming, centrifugal pump comprising a first housing part having a front wall with an inlet, a second housing part having an outlet, an impeller rotatably arranged in the second housing part and a pump screw rotatably arranged in the first housing part, connected to the impeller and comprising a center body around which a helical blade is arranged for feeding the impeller with any gas that is present in the liquid, wherein the center body is arranged at a distance from a side of the front wall that faces the center body, such that a channel with a width of at least 12 mm is formed between the center body and the side of the front wall that faces the center body.

Abstract: A self-priming, centrifugal pump comprising a first housing part having a front wall with an inlet, a second housing part having an outlet, an impeller rotatably arranged in the second housing part and a pump screw rotatably arranged in the first housing part, connected to the impeller and comprising a center body around which a helical blade is arranged for feeding the impeller with any gas that is present in the liquid, wherein the center body is arranged at a distance from a side of the front wall that faces the center body, such that a channel with a width of at least 12 mm is formed between the center body and the side of the front wall that faces the center body.

Abstract: A self-priming, centrifugal pump comprising a first housing part having a front wall with an inlet, a second housing part having an outlet, an impeller rotatably arranged in the second housing part and a pump screw rotatably arranged in the first housing part, connected to the impeller and comprising a center body around which a helical blade is arranged for feeding the impeller with any gas that is present in the liquid, wherein the center body is arranged at a distance from a side of the front wall that faces the center body, such that a channel with a width of at least 12 mm is formed between the center body and the side of the front wall that faces the center body.

Abstract: A self-priming, centrifugal pump comprising a first housing part having a front wall with an inlet, a second housing part having an outlet, an impeller rotatably arranged in the second housing part and a pump screw rotatably arranged in the first housing part, connected to the impeller and comprising a center body around which a helical blade is arranged for feeding the impeller with any gas that is present in the liquid, wherein the center body is arranged at a distance from a side of the front wall that faces the center body, such that a channel with a width of at least 12 mm is formed between the center body and the side of the front wall that faces the center body.

Abstract: A centrifugal pump that includes a casing in which an impeller is arranged. The impeller has a back side that faces a back plate of the centrifugal pump, and one or more vanes for pumping the fluid. The back side of the impeller includes a segmented scraper for scraping from the back plate material that has been deposited from the fluid. The segmented scraper includes multiple protrusions, wherein each protrusion of the multiple protrusions is facing the back plate, and an aggregated radial extension of the protrusions equals a radius of the impeller within an interval of ±10%, ±25% or even up to ±40%.

Abstract: A centrifugal pump that comprises a casing in which an impeller is arranged. The impeller has a back side that faces a back plate of the centrifugal pump, and one or more vanes for pumping the fluid. The back side of the impeller comprises a segmented scraper for scraping from the back plate material that has been deposited from the fluid. The segmented scraper comprises multiple protrusions, wherein each protrusion of the multiple protrusions is facing the back plate, and an aggregated radial extension of the protrusions equals a radius of the impeller within an interval of ±10%, ±25% or even up to ±40%.

Abstract: A tank-cleaning device, having a housing (1) insertable into an opening of a tank, which housing has a rotationally fixed housing part (2) communicating with an ink for the cleaning fluid and a nozzle holder (4) rotatable relative to the rotationally fixed housing part (2) about a first pivot axis (5), and having at least one nozzle assembly with four nozzles (8, 9, 10, 11) that is disposed on the nozzle holder (4) rotatably about a second pivot axis (7), while having a simple structure, enables thorough cleaning of tanks with narrow tank openings, if two nozzles at a time (8, 9; 10, 11) of the nozzle assembly (6) are disposed at an acute angle (12) to one another in the form of respective V-formations (13, 14), and the two V-formations (13, 14) have essentially opposed directions (15).