PG 3.0 Immersion Pumps without Shaft Seal

OPERATING PRINCIPLE: ARBO immersion pumps are single-stage centrifugal pumps designed for installation in open tanks or pits, with the motor positioned above the liquid level and the pump section immersed in the liquid. They are ideal for circulation or liquid transfer applications with either constant or fluctuating liquid levels. The pumps operate using a liquid seal. Centrifugal pumps are non-self-priming, which means that the impeller must be submerged during start-up. By fitting an extended suction pipe (up to a maximum of 2.5 metres), the pump can be adapted for emptying deeper tanks. Only when the liquid level drops to the suction strainer will the pump draw air, causing the liquid seal to be broken. The liquid level must then rise above the impeller before the pump can be restarted.

DRY RUNNING: Thanks to the liquid seal, there is no need for a mechanical shaft seal.

The shaft is of a cantilever, self-centering design, eliminating the need for a foot bearing. There are no friction surfaces within the wetted area, making the pump highly resistant to dry running. Depending on the concentration and abrasiveness of the medium, contaminated or abrasive liquids can be pumped without difficulty.

IMPELLER: This pump series is equipped with a semi-open impeller that is mounted on the shaft independently of the direction of rotation. The pumps are designed to handle solid particles up to Ø 4 mm without causing damage. Even during circulation at a permanently low liquid level, the specially designed impeller prevents air entrainment in the liquid, thereby minimizing foam formation.

CONSTRUCTION: All wetted parts are manufactured from solid plastic materials. Thanks to a special production process and the minimization of welded joints, the risk of chemical stress cracking is virtually eliminated, providing a significant advantage over injection-moulded pumps. The standard material is PPH, offering excellent chemical resistance and a wide range of applications. For highly abrasive liquids with a high solids content, impellers and pump casing components are available on request in RCH-1000 (HMPE – High Molecular Polyethylene). For extremely corrosive media at elevated temperatures, a pump manufactured entirely from PVDF is available. The stainless steel pump shaft is fully encapsulated in plastic, ensuring that no metal comes into contact with the pumped liquid. The shaft sleeve is integrally moulded with the impeller, providing an absolute seal against both liquid and air while achieving optimum dielectric properties. Seals are supplied as standard in EPDM but can also be fitted in Viton or PTFE-lined versions.

ATEX: All immersion pumps can be supplied with Zone II, ATEX II 2G Ex II T3 certification.