Xylem Flygt 5520, Installation, Operation And Maintenance Manual

Page: 14 / 54

Position Part Description
• Wearing cover
• Suction cover
• Impeller
• Wear protection/plug
6 Gasket Functions as a sealing both between
the pump housing and the
discharge line and between the
pump housing and the wear lining.
7 Mechanical seals One inner and one outer seal in a
combination of materials:
• Tungsten carbide
• Silicon carbide RSiC
• Aluminium oxide Al
2
O
3
• Corrosion-resistant
cemented carbide WCCR
8 Oil casing A housing with oil that lubricates
and cools the seals, and acts as a
buffer between the pumped fluid
and the drive unit. Pressure buildup
within the oil casing is reduced by
means of a built in air volume.
9 Main bearing The bearing consists of a two row
angular contact ball bearing.
10 Shaft The shaft is stainless steel, with an
integrated rotor.
11 Cooling The pump is cooled by the ambient
liquid.
12 Support bearing The bearing consists of a single-row
ball bearing.
Monitoring equipment
The following applies to the monitoring equipment of the pump:
• The stator incorporates three thermal contacts connected in series that activate the
alarm and stops the pump at overtemperature
• The thermal contacts open at 125°C (257°F).
• Ex-approved pumps must have thermal contacts connected to the control panel.
• The sensors must be connected to either the MiniCAS II monitoring equipment or an
equivalent equipment.
• The monitoring equipment must be of a design that makes automatic restart
impossible.
• Information in the junction box shows if the pump is equipped with optional sensors.
Optional sensors
FLS FLS is a miniature float switch for detection of liquid in the stator housing. Due to its
design it is best suited for pumps in a vertical position. The FLS sensor is installed in
the bottom of the stator housing.
Product Description
12 Flygt 5520 Installation, Operation, and Maintenance Manual