Replacing Plastic Tubing - ABB Navigator 550 Operating Instructions Manual

Navigator 500
Hydrazine analyzer

8.2.5 Replacing plastic tubing

Warning.

This wet-section contains caustic and other solutions
which must be handled with care. Wear gloves and
eye protection.

Clean up any chemical spillages immediately when
performing this procedure.
In time, certain sections of plastic tubing require replacement,
due to leakage, blockages or poor condition. It is good practice
to replace all plastic tubing every 12 months – re-tubing must be
performed using only the correct tubing lengths and part
numbers – refer to Appendix C, page 69 for part numbers.
Before re-tubing the wet-section, observe the following notes:

Tubing from the calibration and reagent containers and
between the constant-head unit and solenoid valve must
be cut from 1 x 610 mm (24 in.) length of part number
0212186 – refer to Table 8.1, page 56 for the cut lengths
for each connection.

Drain tubing from the constant-head unit (standard and
emergency drains) must be cut from 1 x 480 mm (18.9 in.)
length of part number 0212189 – refer to Table 8.1, page
56 for cut lengths.

Do not modify tubing as this could affect critical flow paths
within the wet-section.
To replace the plastic tubing:
1. Close the sample isolating inlet valve and allow the
wet-section's liquid handling system to drain.
2. Place absorbent tissue at the bottom of the wet-section to
soak up any spillages.
3. Note the arrangement of all tubing.
Referring to Fig. 8.3, page 56:
4. Disconnect the reagent container QD coupling.
A
5. Cut new tubing in half to make 2 x 240 mm (9.45 in.)
lengths and push-fit each length onto the constant head
unit drain stubs.
Feed each length of tubing down through the large holes
in the base of the wet-section and into funnel (see Fig. 3.4,
page 10, for location details).
OI/AHM550–EN Rev. A
6. Fit a 100 mm (4 in.) length of new tubing
constant head unit outlet and solenoid valve.
C
7. Fit new tubing to the sensor overflow drain barbed
connector and feed to the main drain in the base of the
wet-section (see Fig. 3.4, page 10, for location details).
8. Remove the old mixing coil
hydrazine sensor and from the reagent dosing chamber
outlet, unwinding it from the coil former.
D
Connect new tubing
outlet and lead it behind the coil former. Wind on 4
complete turns, ensuring closely spaced and not twisted
and locate the tube in the coil former slot. Ensure that new
tubing has no kinks or restrictions to flow along its length.
Connect to the base of the hydrazine sensor.
E
9. Remove the tube
chamber and the solenoid valve and replace with new
E
tubing .
10. Release the QD coupling from the standard solution
container and remove the tube
valve.
Remove the QD coupling from the tube
11. Fit the QD coupling to a 230 mm (9 in.) length of new
F
tubing and fit the new tube to the solenoid valve –
leave the QD coupling to the container unconnected until
the container has been refilled with standard solution – see
Section 8.1.2, page 53).
12. Release the QD coupling from the reagent solution
container and remove the tube
chamber (top).
Remove the QD coupling from the old tube and retain the
coupling.
13. Fit the QD coupling to a 280 mm (11 in.) length of new
G
tubing and fit the new tube to the solenoid valve –
leave the QD coupling to the container unconnected until
the container has been refilled with reagent – see Section
8.1.1, page 53).
14. Disconnect the sample inlet to constant-head unit tubing
H
and replace with new tubing.
15. Refurbish the hydrazine sensor as required. Follow the
procedure in Section 8.4, page 58.
16. Follow the procedures in Section 4.2, page 19, from step
3 onwards.
B
between the
D
from the base of the
to the reagent dosing chamber
between the reagent dosing
F
from the solenoid
F
.
G
from the dosing
55