Tube / Pipe Lines; Connecting The Suction And Discharge Lines - Grundfos DDI 222 Instrucciones De Instalación Y Funcionamiento

• When installing the suction line, observe the following:
– Keep the suction line as short as possible. Prevent it from
becoming tangled.
– If necessary, use swept bends instead of elbows.
– Always route the suction line up towards the suction valve.
– Avoid loops as they may cause air bubbles.
Fig. 13 Installation of suction line
• In the case of long discharge lines, install a non-return valve
(12i) in the discharge line.
11i
Fig. 14 Installation with non-return valve

5.5 Tube / pipe lines

5.5.1 General
Warning
To protect the dosing pump against excessive
pressure build-up, install a relief valve in the
discharge line.
All lines must be free from strain!
Avoid loops and buckles in the tubes!
Keep the suction line as short as possible!
The flow must run in the opposite direction to gravity!
Observe the manufacturer's safety instructions when
handling chemicals!
The resistance of the parts that come into contact
with the media depends on the media, media
temperature and operating pressure. Ensure that
parts in contact with the media are chemically
Caution
resistant to the dosing medium under operating
conditions!
Only use the specified line types!
Maximum suction line length
• 5 m for standard pumps when dosing media with a viscosity
similar to water and using a pulsation damper.
• 1.2 m when dosing media with a higher viscosity than water.
• 1.2 m for pumps with Flow Monitor (2 m for standard
DDI 60-10) when dosing media with a viscosity similar to water
and not using a pulsation damper.
16
12i
5.5.2 Sizing of tube / pipe lines
Warning
Observe the pressure stage of the used lines. The
maximum permissible inlet pressure and the
pressure stage of the discharge lines must not be
exceeded!
Minimum internal diameter
Pump type Standard
[mm]
Suction side: 9
DDI 60-10
Discharge side: 6
DDI 150-4 13

5.5.3 Connecting the suction and discharge lines

• Connect the suction line to the suction valve (3a).
– Install the suction line in the tank so that the foot valve
remains approximately 5 to 10 mm above the bottom of the
tank or the possible level of sedimentation.
• Connect the discharge line to the discharge valve (3b).
3b
B
3a
A
C
C
Fig. 15 Connecting the suction and discharge lines
Pos. Components
3a Suction valve
3b Discharge valve
C Pipe connection
D Tube connection
Observe the pressure limits specified in section
Caution
1. General information
Pump version
HV variant
[mm]
Suction side: 19
Discharge side: 13
Suction side: 19
Discharge side: 13
D
D
!