Leaks can occur at any tubing connection, gasket, or seal but are most common at tubing
connections. Low pressure leaks (on the intake side of the solvent manager’s pump) cause
solvent loss and air introduction during the intake cycle. Leaks at high pressure fittings
(downstream of the "intelligent" intake valves) can leak solvent but do not introduce air.
To prevent leaks, follow Waters’ recommendations for the proper tightening of system fittings.
Note that different techniques apply to re-tightening fittings versus installing them for the first time.
2.5.1 Installation recommendations for fittings
Three types of fitting assemblies are used within the system: PEEK (polymer-based), SST
(stainless steel), and MP35N (alloy-based). When connecting tubing, heed the following
recommendations for installing and tightening fittings.
Warning:
Observe Good Laboratory Practice (GLP) at all times, particularly when
working with hazardous materials. Consult the Material Safety Data Sheets regarding
the solvents you use. Additionally, consult the safety representative for your
organization regarding its protocols for handling such materials.
Warning:
To avoid personal contamination with biologically hazardous materials, wear
clean, chemical-resistant, powder-free gloves when performing this procedure.
Requirement:
Wear clean, chemical-resistant, powder-free gloves when performing
this procedure.
Requirement:
Use eye protection when performing this procedure.
Recommendations:
• To prevent band spreading, ensure that the tubing is fully bottomed in its connection port
before tightening the compression screw.
• For easier accessibility, use long compression screws to attach tubes to the injector and vent
valve.
• Perform the solvent manager leak test whenever you replace or loosen fittings during
maintenance (see the console online Help).
• Whenever you loosen fittings during maintenance, examine for cracks, stripped threads, and
deformations.
• Do not reuse stainless steel fittings more than six times.
2.5.1.1 Assembling new fittings
For metallic (SST or MP35N) fitting and tubing assemblies with ferrules not previously assembled
or set to tubing, you must mark the compression screw and connection port and ensure that the
two marks line up when you tighten them.
April 4, 2018, 715005702 Rev. A
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