N/A

The intermediate shafts and the pump shaft are carried in sleeve bearings which are corrosion and abrasion resistant. The maximum space between the shaft guide bearings follows the recommendation of API 610.

Several sleeve bearing options are available. E.g. for handling liquids with solids we can offer pure and wear resistant Silicon Carbide bearing sets.

N/A

Design
The chemical submersible pump NMT is a single-stage volute casing pump with separate column pipe and discharge pipe. The hydraulic part of the pump is mounted inside of the vessel, the driving motor is located outside. All standard motors with normal shaft design can be used. No special shaft design is required. The driven rotor is mounted to the motor shaft. Power is transmitted to the drive shaft through the magnetic coupling. Submersible length according to customer's specification.

Volute casing
The volute casing is a one piece casting and bolted to the column pipe via the intermediate casing. In case the liquid temperature drops below the melting- or crystallization point, volute casings and tubes with heating jackets are available. For example: handling of sulphur liquid or viscose residuals or sump liquids.

Impeller
The standard design of the DICKOW® submersible pump has a closed impeller. The impeller is cast in one piece and hydraulically balanced to reduce thrust loads to a minimum. All impellers are dynamically balanced, according to DIN ISO 1940T1 balance grade 6.3 which grants a smooth vibration free operation. Finer balancing grades are available on request.

The impellers are placed on the pump shaft in overhung position and secured by key and nut.

Wear rings
The volute casings and the intermediate casings of the NMT-pumps are fitted with renewable wear rings as standard. The running clearances between casing wear rings and impeller comply with the recommendation of API 610.

Shaft
The shaft assembly consists of the drive shaft, one or more intermediate shafts and the pump shaft. These shafts are connected by rigid metallic plug-in couplings, secured by keys and locking fasteners.

Discharge pipe, column pipe
The discharge and column pipes consist of seamless pipe material with welded connection flanges.

Dome cover plate (mounting flange)
Standard material for the cover plate is carbon steel, 1.4571 (AISI 316Ti) S.S. is available as an option on request.

The cover plate with the drilled holes for pump installation on site is made according to customer's specification, or approved dimensional drawing.

If the pump is supposed to be installed in a pressurized vessel, the thickness of the cover plate will be calculated and sized according to the German Pressure Vessel Code. Material certificates 3.1 can be supplied on request.

N/A

The containment shell is designed as a pressure vessel to separate the pumpage from the atmosphere only. The containment shell is not used as an additional bearing holder. No dynamic stress occurs. The containment shell is bolted to the bearing housing in a manner that allows removal of the motor, including outer magnets without exposing the pumped liquid to the atmosphere.