Waters 2998, Обзор и руководство по обслуживанию

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December 5, 2017, 715004753 Rev. B
Page 39
Tip:
Keep the length of this tubing as short as possible, to prevent band broadening.
2. Measure the length of tubing needed to connect the detector outlet to a waste collection
bottle.
Tip:
Ensure that the length of this tubing is at least 30 to 60 cm (1 to 2 feet), to prevent air
bubbles from forming in the flow cell.
3. Cut the two lengths of tubing as follows:
a. Use a Waters 1/16-inch stainless steel tubing cutter or a file with a cutting edge to
scribe the circumference of the tubing at the desired break point.
b. Grasp the tubing on both sides of the scribed mark with cloth- or plastic-covered pliers
(to prevent marring the surface), and then gently work the tubing back and forth until it
separates.
c. File the tubing ends smooth and straight, to minimize dead volume and band
broadening.
4. Assemble a reusable finger-tight fitting at both ends of the column-outlet line and at one end
of the detector outlet line.
5. Seat one end of the column-outlet tubing in the fitting of the column outlet, finger-tighten the
reusable, finger-tight fitting to the extent possible until it is snug, and then add a quarter
turn.
6. Seat the free end of the column outlet tubing in the fitting of the detector inlet, and then
tighten the reusable finger-tight fitting as in step 5.
7. Seat the end of the detector outlet tubing with the reusable finger-tight fitting in the detector
outlet fitting, finger-tighten the fitting to the extent possible, and then add a quarter turn.
8. Insert the free end of the detector outlet tubing in the waste container.
9. Slide the 3/8-inch OD Tygon
®
tubing, supplied in the startup kit, over the barbed drain fitting
on the drip tray, and route the tubing to a suitable waste container.
Tip:
For instructions explaining how to install the multi-detector drip tray see the installation
instructions provided with the drip tray.
2.7.1 Connecting the detector to the gas supply
You can connect the detector to a nitrogen source, to improve operation at lower wavelengths.
Requirement:
Use only a constant supply of dry, oil-free, filtered nitrogen at pressure between 28
to 41 kPa (.28 to.41 bar, 4 to 6 psi).
Notice:
To avoid damaging the flow cell, avoid exposing it to pressures that approach
its maximum allowable pressure of 6895 kPa (69 bar, 1000 psi) (70 kg/cm
2
).
Compression
screw or nut
Tube
End must be straight
and smooth, to achieve
maximum column
efficiency
Critical distance to be determined by the
union or column fitting
Ferrule