Page 24 - Plastics News June - 2020

Ÿ Purge throat and barrel completely dry with PP.
Ÿ With screw empty, suck screw back 1 in.
Ÿ Shut off hot runner.
Ÿ Spray mold lightly with rust preventative.
Ÿ Close mold, not under tonnage, with mold faces
touching.
Ÿ Shut off water at main valves.

If the press will be down for 30 min or less:
Ÿ Retract carriage to separate tip from bushing.
Ÿ Inspect tip for blowback.
Ÿ Run screw forward to remove shot from barrel.
Ÿ Remove purge from press bed.
Ÿ With screw empty, suck screw back 1 in.
Weekend Shutdown:
Ÿ Remove purge from press bed.
Ÿ Retract carriage to separate tip from bushing.
If downtime length is unknown or longer than 30 min but
Ÿ Inspect tip for blowback.
less than 4 hr:
Ÿ Purge throat and barrel completely dry with PP.
Ÿ Retract carriage to separate tip from bushing.
Ÿ With screw empty, suck screw back 1 in.
Ÿ Inspect tip for blowback.
Ÿ Shut off hot runner.
Ÿ Purge throat and barrel completely dry with
Ÿ Spray mold with rust preventative.
polypropylene.
Ÿ Close mold, not under tonnage, with mold faces
Ÿ With screw empty, suck screw back 1 in.
touching.
Ÿ Shut off hot runner.
Ÿ Shut off water at main valves.
Ÿ Remove purge from press bed.
Ÿ Bank dryer at 100 F.
If downtime will be 4 hr or full shift:
Failing to close the slide on shutdown can lead to a
Ÿ Retract carriage to separate tip from bushing.
bridged throat and excessive downtime.
Ÿ Inspect tip for blowback.

June 2020 24 Plastics News