Cold Jet P1500 - Troubleshooting Specific Issues; CO2 Vapor and Hydraulic Pressure; Oil Filter and Piston Movement

Operation Manual P750/P1500/P3000
Cold Jet, LLC Page 25
• Snow plugs are typically the result of the liquid CO
2
valve being opened on an
unpressurized machine when the supply pipe is cold and the liquid CO
2
is already at
the machine inlet.
• The incoming liquid experiences an immediate pressure drop and "flashes to snow",
forming a plug in the liquid CO
2
line.
CO
2
Vapor Pressure
The vapor pressure gauge may range from 150 to 300 psig (10.3 to 20.7 bar). It is not always
the same as the liquid CO
2
pressure. The CO
2
vapor supply must maintain at least 150 psig
(10.3 bar) during the purge and chill cycles.
Hydraulic Pressure
The hydraulic pressure should increase from 1000 psig to 2500-3000 psig (69 bar to 172.4-
206.8 bar) - this depends on the die plate size - during the extrusion portion of the production
cycle. The high pressure portion of the cycle requires only 8 to 9 sec to complete, or 12-13 sec
for the piston to advance from the rear proximity switch to the front one after operating for at
least 30 minutes.
Oil Filter Pressure
The Oil Filter pressure will average 5 - 8 psig (0.4 - 0.6 bar) except on the return stroke of either
cylinder; the gauge will indicate 10 psig (0.7 bar). When the pressure exceeds 20 psig (1.4 bar),
the filter element needs to be replaced.
CO
2
Vapor Pressure
The vapor pressure gauge may range from 150 - 300 psig. (10.3 - 20.7 bar) It is not always the
same as the liquid CO
2
pressure. The CO
2
vapor supply must maintain at least 150 psig (10.3
bar) during the purge and chill cycles.
No Piston Movement
When the chamber power switch is off, press the reset button and turn the chamber power
switch on. If the machine does not operate, check the following:
• Check fuse 3 for a possible OFF position.
• If Rotary Knives are installed, check fuse 5. If blown, an indicator light will be on the
blown fuse. Piston movement will stop in the cylinder with the blown fuse. The
damaged side is jammed with CO
2
“snow” or water ice. Remove the jammed elbow and
clear the ice, then re-install it and resume production.
• With the Pelletizer in “standby” mode the hydraulic pressure should be 400 psig (27.6
bar) or less.
o Turn the hydraulic pump off.