Grundfos Inline single stage pump TPD 65-250/2 A-F-A-BQQE-KW1

Single-stage, close-coupled, volute twin-head pump with in-line suction and discharge ports of identical diameter. The
twin-head pump is designed with two parallel power-heads. The pump is of the top-pull-out design, i.e. the power
head (motor, pump head and impeller) can be removed for maintenance or service while the pump housing remains
in the pipework.
Each power head is fitted with an unbalanced rubber bellows seal. The shaft seal is according to EN 12756. Pipework
connection is via PN 16 DIN flanges (EN 1092-2 and ISO 7005-2).
Each power head is fitted with a fan-cooled asynchronous motor of indentical size.
The product’s minimum efficiency index (MEI) is greater or equal to 0.70. This is by the Commission Regulation (EU)
considered as an indicative benchmark for best-performing water pump available on the market as from 1 January
2013.
Pump
1: Pump housing
2: Impeller
3: Stub shaft
4: Pump head/motor stool
5: Wear rings
The twin-head pump is designed with two parallel power-heads. A non-return flap valve in the common discharge port
is opened by the flow of the pumped liquid and prevents backflow of liquid into the idle pump head.
The pump housing is provided with a replaceable brass neck ring to reduce the amount of liquid running from the
outlet side of the impeller to the inlet side.
The impeller is secured to the shaft with a nut.
The pump is fitted with an unbalanced rubber bellows seal with torque transmission across the spring and around the
bellows. Due to the bellows, the seal does not wear the shaft, and the axial movement is not prevented by deposits
on the shaft.
Seal faces:
• Rotating seal ring material: silicon carbide (SiC)
• Stationary seat material: silicon carbide (SiC)
This material pairing is used where higher corrosion resistance is required. The high hardness of this material pairing
offers good resistance against abrasive particles.
Secondary seal material: EPDM (ethylene-propylene rubber)
EPDM has excellent resistance to hot water. EPDM is not suitable for mineral oils.
A circulation of liquid through the duct of the air vent screw ensures lubrication and cooling of the shaft seal.
The pump housing has four Rp 1/8 tappings for mounting of automatic air vents. Fit an air vent to the upper pump
housing if the twin-head pump is to be installed in a horizontal pipeline with horizontal pump shaft.
The flanges have tappings for mounting of pressure gauges.
The motor stool forms connection between the pump housing and the motor, and is equipped with a manual air vent
screw for venting of the pump housing and the shaft seal chamber. The sealing between motor stool and pump
housing is an O-ring.