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8 Maintenance and Care of the TitroLine
®
5000
The preservation of the proper functioning of the piston burette requires testing and maintenance work
to be performed on a regular basis.
Regular inspections are essential prerequisites for the correctness of the volume and the proper
functioning of the piston burette.
The accuracy of the volume is determined by all chemicals-carrying components (piston, cylinder,
valve, titration tip and hoses). These parts are subject to wear and tear, i.e. zthey are or wearing parts,
respectively. The piston and cylinder are subject to particular strain, hence they require special
attention.
Heavy strain:
Use of e.g. concentrated solutions, reagents and chemicals (> 0.5 mol/L); chemicals attacking glass,
such as fluorides, phosphates, alkali solutions; solutions with a tendency to crystallising out; Fe (III)
chloride solutions; oxidising and corroding solutions such as iodine, potassium permanganate, Cer
(III), Karl-Fischer titration agent, HCl; solutions with a viscosity of > 5 mm
2
/s; frequent, or even daily
use.
Normal strain:
Use of solutions, reagents and chemicals (up to 0.5 mol/l) which do not attack glass, crystalize out or
corrode.
Interrupted use
:
If the dosing system is not in use for more than two weeks, we recommend emptying and cleaning the
dosing unit [6]. This applies in particular under the operating conditions referred to in the „Heavy
strain” section. If this recommendation is not adhered to, the piston of the valve may become leaking,
this may result in damage to the piston burette.
If the liquid is left within the system, you will also have to reckon with corrosion and an alteration of
the solutions used over time, which includes e.g. crystallisation. Considering that as of the state of the
art there are no plastic hoses available for the use in titration equipment which would be perfectly free
of diffusion phenomena, particular attention is to be paid to the range of the hose lines.
We recommend the following inspection and maintenance work
Heavy strain
Normal strain
Simple cleaning:
Wiping off splashed chemicals from the outer surface. [1]
Whenever required in
operation
Whenever required in
operation
Sight check:
Check for leakage in the area of the dosing system. [2]
Is the piston tight? [3]
Is the valve tight? [4]
Titration to clear? [5]
Weekly, when putting
back into operation
Monthly, when putting
back into operation
Basic cleaning of the dosing system:
All parts of the dosing system to be cleaned separately. [6]
Every three months
Whenever necessary
Technical inspection:
Check for air bubbles in the dosing system. [7]
Visual inspection
Check of the electrical connections. [8]
Semi-annually when
putting back into
operation
Semi-annually when
putting back into
operation
Verification of the volume according to ISO 8655:
Perform basic cleaning
Inspection according to ISO 8655 Part 6 or Part 7. [9]
Semi-annually
Annually
