Hydraulic pump part
The hydraulic pump parts are located in the pumping fluid respectively in the tank. The pump parts consist of suction- and discharge casing, intermediate casings, diffusers and impellers. The discharge casing is bolted to the bottom column pipe. The closed impellers are hydraulically balanced by balance holes and wear rings to keep the thrust loads as small as possible.
The support columns are made of seamless steel tube with welded neck connection flanges. The number of column pipes is determined by the submerged length and the pump speed.
Pump shaft, column shaft(s), drive shaft
The complete shaft consists of the pump shaft, one or more column shafts and the drive shaft. The single shafts are rigidly connected through screwed sleeve couplings.
The maximum lengths of the column shafts comply with the recommendations of the API 610 and are dimensioned to guarantee subcritical speed characteristics throughout the whole operating range.
The all-metal sleeve coupling consists of the sleeve, the lock nuts and the fixing screws.
The power is transmitted via the keys, the sleeve is fixed vibration-free and secured by the lock nuts. The distance "a" between the shaft ends can be adjusted.
Drive lantern (motor support)
The drive lantern is a welded construction of seamless steel tube. Discharge flange, motor hub flange and the flange for connection to the dome cover are welded to the drive lantern. Shaft sealing and antifriction bearings are also located in the drive lantern.
The motor is connected to the drive lantern above the dome cover. IEC-motors of design V1 are used as standard. NEMA-motors with US-dimensions can be used as an option.
The motors are connected to the drive shaft with a suitable coupling. If spacer-type couplings are used, repair works on bearings and shaft sealing can be carried out without removal of the motor.
Dome cover (mounting flange)
Standard material of the dome cover is carbon steel. Stainless steel material 1.4571 (ASME 316L) is available on request. The dome covers are generally made according to the mounting flange dimensions of the tank, as long as they can accommodate the outer diameter of the pump body.
If the tanks are pressurized, the covers will be sized and manufactured according to the applicable standards.
For handling boiling liquids (e.g. condensate) and if very low NPSH-values are required, the HZV pump with barrel casing is available.
Dimension "H" is determined as follows:
H = NPSHR - NPSHA + 0.5 m
(NPSHR - acc. to performance curve, 0.5 m is safety margin)