The DICKOW® medium duty pumps type NCL are single-stage, single-flow volute casing pumps in back pull out design, with an end suction flange and a centerline discharge flange. Bearing housing with intermediate casing, shaft sealing and impeller is mounted to one unit.
With the back pull out design, unit can be removed without demounting the pipe connections.
If spacer type couplings are used, the motor can also remain bolted on the base plate.
The pump casing of standard design is cast in one piece and foot mounted on the base plate. The casing is sealed to the atmosphere by confined non-asbestos gaskets.
If required, following special designs are available:
Volute casing with heating jacket
Pumps with heating jacket are required if the liquid temperature decreases when flowing through the pump or when the liquid temperature drops below the melting or crystallization point. For example: Dimethylterephthalat (DMT), sulphuric liquid, Phenol etc.
Heating jackets on volute and intermediate casings with welded cover are designed for heating liquids up to 24 bar/350 psi and 220 ºC/ 430 ºF.
API 610, requires centerline-mounted pressure casings, if the pumping fluid temperatures are 177 ºC (350 ºF) or higher. All NCL-types can be delivered with centerline supported pressure casings.
Volute casing and intermediate casing of NCLs-types are both fitted with renewable wear rings held in place by a press fit with locking screws. Additional impeller wear rings available as an option. The running clearances are in accordance with API 610.
Shaft, shaft sleeve
The pump shaft is able to transmit the full driver output and is accurately machined throughout his entire length and is properly finished at the bearing surfaces.
In order to have satisfactory seal performance the shaft diameter and overhung are sized to minimize shaft deflection at the seal faces. The shaft construction guarantees a critical speed of more than 10% over the maximum operating speed. The connections "cap screw - hub" and "hub - shaft sleeve" are sealed by confined gaskets and the pump shaft has no contact to the pump fluid.