N/A Closed impellers are standard. Impellers are casted in one piece with solid hubs. To minimize the axial load of the bearings, the impellers are fitted with wear rings on the back and balance holes to the suction. Impellers are properly statically and dynamically balanced in acc. to DIN ISO 1940T1 Grade 6.3.
For handling liquids, containing solids such as slurry and suspensions up to discharge 3", the NCLo-type with open impeller is available.
NCLo-pumps are fitted with renewable wearing disks on suction side to minimize maintenance costs. For discharge sizes 4" and bigger semi open impellers are available.

The overhung mounted impellers are secured on the shaft by means of a key and a cap screw with Heli-Coil insert.

N/A The pump shaft is carried by generously dimensioned antifriction bearings outside the pumped liquid. The bearings are oil lubricated. The oil level is regulated by constant level oiler.

Double-row angular ball bearings of Conrad-type (no filling slots) on coupling side, roller bearing on pump side. Service life 25000 hours at continuous operation.

Bearing housing
Bearing housings of NCL-pumps are of split design. Therefore, it is possible to supply the pump sided bearing bracket lantern of corrosion resistant material when handling aggressive liquids.

The pump sided radial seal ring located in the bearing bracket lantern is protected by an additional deflector which avoids entrance of leakage from mechanical seal. The bearing bracket lantern is designed as drip pan and provided with leakage connections.

If required, bearing bracket cooling is also available.

N/A To have the advantages of a fine subdivided performance range with many pump types without disadvantage of a large spare part stock, the NCL-types are designed in a unit-composed system. Therefore you need for all sizes of pumps only four bearing sizes, four mechanical seal sizes, four shafts a.s.o. Further, many parts in different pump types are similar and interchangeable with another.

N/A Stuffing box
Stuffing boxes are fitted with split cages and split stuffing box ring for an easy replacement of packing rings. Internal circulation or external flushing is possible.
Mechanical seals can be installed in the stuffing box chamber on site, no re-machining of parts required.

N/A Pumps can also be fitted with all kind of mechanical seals such as single, tandem or double seals.
Heating or cooling of the seal is possible. Single seals can be equipped with throttle bushings, quench connections or auxiliary stuffing box. Seal glands are fitted with confined non-asbestos gaskets to prevent blow outs.

N/A Construction
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.

Volute casing
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.

Centerline-mounted casing
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.

Wear rings
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.