The NKLs-HTM pumps are single stage, single flow volute casing pumps of horizontal back-pull- out design with end suction and top discharge flanges. The back-pull-out design allows disassembly of the bearing bracket unit, complete with impeller, intermediate casing and mechanical seal without removing the volute casing from the piping system.
Volute casing, Flange design
The one-piece radial split volute casing is provided with rigid integrally cast feet for mounting on the base plate.
Standard suction and discharge flanges have raised face. Flat face or groove are available as option.
The volute casings of the NKLs-standard pumps have no wear rings provided. However, the design of the casings allows remachining and a subsequent installation of wear rings in case of worn out mating surfaces.
NKLs-pumps have closed impellers, cast-en-bloc, hydraulically balanced by throttle gap and relief bores to minimize axial loads. All impellers are dynamically balanced acc. to DIN ISO 1940 part 1, at a balance grade of G 6.3, that grants a smooth and vibration free operation of the pump. The impellers are arranged on the pump shaft in overhung position and are fixed by keys and shaft nuts with Heli-Coil inserts.
The pump shafts are capable for receiving the driving power transmission. Minor deflections ensure a high reliability of operation. The pump shafts are manufactured of corrosion resistant material.
Volute casing: GGG40.3
Intermediate casing: GGG40.3/S137
Pump Shaft: 1.4021
Bearing bracket GG25
The pump shaft is carried in generously dimensioned antifriction bearings. Two bearings are positioned at pump- and coupling side outside the pumped liquid. There is no additional sleeve bearing unit available in the fluid. Oil lubrication is standard. The oil level in the bearing bracket is controlled by constant level oiler. Service life of the bearings reaches 20,000 operating hours.