
Hydraulic installations
Hydraulic connections
19
Subject to technical changes.
Stepper motor-driven diaphragm dosing pump NXP-M and NXP-P
Operating instructions
8.2 System piping
n
The system piping must not exert any force on the connections and
valves of the dosing pump.
n
This means that steel piping should be connected to the dosing pump
by means of flexible pipe sections.
n
The nominal diameters of the pipework and the installed fittings
should be rated the same as or greater than the nominal diameters of
the dosing pump's suction and discharge valves.
n
The suction line should be kept as short as possible.
n
You should avoid intertwined hoses.
n
Avoid loops, since air bubbles can collect.
8.3 Aligning the dosing head
a
b
c
Fig. 12: Aligning the dosing head
When connecting the dosing lines to the dosing pump, you must observe
the direction of through-flow (see arrow 2). The dosing head must be
aligned vertically. The alignment can be changed in 90° intervals.
The suction valve (3) must always point downwards. Accordingly, arrow
(2) and pressure valve (1) always point upwards. This is irrespective of the
positioning of the dosing head to the drive.
8.4 Hydraulic connections
8.4.1 Connecting hose clips
Choose the hose connection according to the condition of the hose
(material, inner diameter, wall thickness) in order to ensure maximum
pressure resistance.
8.4.1.1 Size 4/6
a
b
c
d
e
a
b
c
d
e
4/6
6/9
Fig. 13: Hose clips 4/6 and 6/9 (internal and external diameters in mm)
Perform the following working steps:
1.
Cut the hose (1) to the appropriate length neatly and at an exact right
angle.
2.
Place a gasket that is suitable for the dosing medium between the
connection (5) and the valve.
3.
Screw the connecting piece to the dosing pump's valve using the
union nut (2).
4.
Thread the union nut (3) and the clamping ring (4) onto the hose.
5.
Plug the hose all the way in to the grommet of connection piece.
6.
Push the clamping ring onto the grommet of connection piece and
screw it to the union nut.
7.
Carry out the same procedure with the connection to the dosing
pump's other valve.
ü
Hose clip connected.