Waters XSelect CSH130 C18 3.5 μm and 5 μm Columns - Manual (Page 6)

[ CARE AND USE MANUAL ]
XSelect CSH130 C
18
Columns 6
V. CONNECTING THE COLUMN TO THE HPLC
a. Column Connectors and System Tubing Considerations
Tools needed:
• 3/8 inch wrench
• 5/16 inch wrench
Handle the column with care. Do not drop or hit the column on a hard surface
as it may disturb the bed and affect its performance.
1. Correct connection of 1/16 inch outer diameter stainless steel
tubing leading to and from the column is essential for high-
quality chromatographic results.
2. When using standard stainless steel compression screw fittings, it
is important to ensure proper fit of the 1/16 inch outer diameter
stainless steel tubing. When tightening or loosening the compres-
sion screw, place a 5/16 inch wrench on the compression screw
and a 3/8 inch wrench on the hex head of the column endfitting.
Note: If one of the wrenches is placed on the column tube flat during this
process, the endfitting will be loosened and leak.
3. If a leak occurs between the stainless steel compression screw
fitting and the column endfitting, a new compression screw
fitting, tubing and ferrule must be assembled.
4. An arrow on the column identification label indicates correct
direction of solvent flow.
Correct connection of 1/16 inch outer diameter stainless steel tubing lead-
ing to and from the column is essential for high-quality chromatographic
results. To obtain a void-free connection, the tubing must touch the bottom
of the column endfitting. It is important to realize that extra column peak
broadening due to voids can destroy an otherwise successful separation. The
choice of appropriate column connectors and system tubing is discussed in
detail below.
Figure 1: Waters and Parker Ferrule Types
Waters Ferrule Setting
0.130 inches
Parker Ferrule Setting
0.090 inches
.130” .090”
Due to the absence of an industry standard, various column manufacturers
have employed different types of chromatographic column connectors. The
chromatographic separation can be negatively affected if the style of the
column endfittings does not match the existing tubing ferrule settings. This
section explains the differences between Waters style and Parker style ferrules
and endfittings (Figure 1). Each endfitting style varies in the required length
of the tubing protruding from the ferrule. The XBridge column is equipped
with Waters style endfittings that require a 0.130 inch ferrule depth. If a non-
Waters style column is presently being used, it is critical that ferrule depth be
reset for optimal performance prior to installing a XBridge column.
In a proper tubing/column connection (Figure 2), the tubing touches the bottom
of the column endfitting, with no void between them.
Figure 2: Proper Tubing/Column Connection
The presence of a void in the
flow stream reduces column
performance. This can occur if a
Parker ferrule is connected to a
Waters style endfitting (Figure 3).
Note: A void appears if tubing with a Parker ferrule is connected to a Waters
style column.
Figure 3: Parker Ferrule in a Waters Style Endfitting
There is only one way to fix this problem: Cut the end of the tubing with the
ferrule, place a new ferrule on the tubing and make a new connection. Before
tightening the screw, make sure
that the tubing bottoms out in the
endfitting of the column.
Conversely, if tubing with a Waters ferrule is connected to a column with
Parker style endfitting, the end of the tubing will bottom out before the
ferrule reaches its proper sealing position. This will leave a gap and create
a leak (Figure 4).
Note: The connection leaks if a Waters ferrule is connected to a column with
a Parker style endfitting.
Void