SPEX SamplePrep 6875 Freezer/Mill Series - Liquid Nitrogen Connection

6875 Freezer/Mill
Page 28 of 42 SPEX® SamplePrep LLC DEC 2015
7.2 Liquid Nitrogen Connection
Install the safety valve on the outlet of the tank or LN line, with the gooseneck tilted up and the
valve outlet down (see Figure 14). Then attach the LN transfer hose to the safety valve, and the
other end to the inlet on the Freezer/Mill. The safety valve should be higher than the LN inlet on
the Freezer/Mill. The purpose of the safety valve is to have an outlet for nitrogen vapor in case
the mill and supply tank valves are both shut, and pressure builds up inside the hose.
When installing the safety valve and transfer hose, use Teflon plumber’s tape on all joints, and
tighten the nuts with a wrench. If the joints leak, tighten them further and/or use more tape.
Safety Valve
1/2” female JIC
connects to LN Tank or
LN line
1/2” female JIC
LN Transfer Hose
3/8” female NPT
3/8” male NPT
1/2” female JIC
1/2” male JIC
on 6875
Swivel Joint
Adapter
Apply Teflon Tape Here
Figure 14 – Liquid Nitrogen Connection (LN Transfer Hose Sold Separately)