Wilo FKT 50.1 Series Installation And Operating Instructions Manual page 172

en
4.1.2 Motor
4.1.3 Cooling system
4.1.4 Seal
4.1.5 Material
172
Product description
The hydraulics are not self-priming, in other words, the fluid must flow in either auto-
matically or with supply pressure.
Impeller shapes
The individual impeller shapes depend on the size of the hydraulics and not every im-
peller shape is available for every hydraulic system. The following is an overview of the
different impeller shapes:
▪ Vortex impeller
▪ Single-channel impeller
▪ Two-channel impeller
▪ Three-channel impeller
▪ Four-channel impeller
▪ SOLID impeller, closed or half open
Inspection cover (depending on the hydraulics)
Additional opening on the hydraulics housing. This opening is used to remove clogging
in the hydraulics.
Casing and impeller wear rings (depending on the hydraulics)
The suction port and impeller are subjected to the most stress when pumping. In the
case of channel impellers, the gap between the impeller and the suction port is an im-
portant factor for a constant efficiency. The larger the gap between the impeller and
the suction port, the higher the losses in the delivery rate. The efficiency decreases and
the danger of clogging increases. In order to ensure long and efficient operation of the
hydraulics, an impeller wear ring and/or casing wear ring is installed depending on the
impeller and the hydraulics.
▪ Impeller wear ring
The impeller wear ring is attached to the channel impellers and protects the incoming
flow edge of the impeller.
▪ Casing wear ring
The casing wear ring is installed in the suction port of the hydraulics and protects the
incoming flow edge in the centrifugal chamber.
The two components can be replaced easily when worn.
In the three-phase current version, self-cooling submersible motors are used as the
drive. The motor can be used in continuous duty both immersed and non-immersed.
Continuous duty is also possible in dry well installation. The resulting condensate is col-
lected in a separate chamber and can be drained off. The upper roller bearing is per-
manently lubricated and thus maintenance-free, the lower roller bearing must be regu-
larly greased. The connection cable is longitudinally watertight and has bare cable ends.
The motor has an active cooling system with separate cooling circuit. The water-glycol
mixture P35 is used as coolant. Coolant circulation is performed by an impeller. The im-
peller is driven by the motor shaft. The waste heat is transferred directly to the fluid via
the cooling flange. The cooling system is not pressurised when in cold state.
The fluid and the motor compartment are sealed by two separate mechanical seals. The
sealing chamber version is one of two types, depending on the motor size:
▪ FKT 50.1, FKT 57, FKT 63.1: The sealing chamber and the cooling system form a one-
chamber system. The sealing chamber and the cooling system are filled with P35
coolant.
▪ FKT 63.2: The sealing chamber and the cooling system form a two-chamber system.
The sealing chamber is filled with medicinal white oil and the cooling system is filled
with P35 coolant.
Leakage from the seal is caught in the sealing chamber or leakage chamber:
▪ The sealing chamber accommodates any possible leakage of the seal on the fluid side.
▪ The leakage chamber accommodates any possible leakage of the seal on the motor
side.
The following materials are used in the standard version:
▪ Pump housing: EN-GJL-250 (ASTM A48 Class 35/40B)
▪ Impeller: EN-GJL-250 (ASTM A48 Class 35/40B)
▪ Motor housing: EN-GJL-250 (ASTM A48 Class 35/40B)
▪ Seal:
WILO SE 2019-01