Injection Moulding Die Change and Process Setup Procedure

Purpose. This procedure sets out how a setter removes a die, fits the next die and establishes the process from the setting sheet through to first-off approval, safely and to specification.

1.Preparation

Before the changeover the setter must read the job card and the Process Setting Sheet for the next tool, check the tool register for the tool's condition and last service, confirm the material is dried to the sheet and that the correct hot runner controller, core pullers, robot gripper and ancillaries are available. Stage the tool, clamps, bolts, lifting gear and hoses at the machine before stopping the current run.

2.Isolation for die removal

Run the barrel down and stop the machine. Isolate and lock out the machine at the main isolator with your personal lock, release hydraulic pressure and drain the accumulator, isolate and vent the pneumatics, isolate the mould heating and cooling and disconnect hoses. Test that the machine will not start. Support the mould with the crane before removing clamps and never place a hand between the platens or mould halves unless the machine is locked out and the mould is supported.

• Personal lock on the main isolator
• Hydraulic pressure released, accumulator drained
• Pneumatic supply isolated and vented
• Heating and cooling isolated, hoses disconnected
• Mould supported by the crane before clamps are removed

3.Fitting the new die

Clean the platens and check the locating ring and sprue bush. Lift the mould with the rated lifting gear and locate it on the fixed platen, clamp it and close the moving platen at low pressure to clamp the moving half. Fit all clamps to the torque on the sheet. Connect cooling, hydraulic cores and hot runner leads to the identified ports. Remove your lock only when all hands are clear and the guards are closed.

4.Establishing the process

Set the barrel and hot runner temperatures, mould temperature, injection speed and pressure profile, holding pressure and time, cooling time, shot size, cushion and clamp force exactly from the Process Setting Sheet. Set the mould open and close protection and check the ejection stroke at low speed with the guards closed. Purge the barrel into the purge station. Run the first shots in semi-automatic and inspect them.

5.First-off approval

Take five consecutive shots after the process has stabilised. Measure the dimensions and weight on the drawing and the sheet, check appearance for short shots, flash, sink, burns and splay, and check any inserts or labels. Record the results on the first-off section of the job card. The run must not continue in automatic until the setter has signed the first-off as approved. If the parts do not conform, adjust only within the limits on the sheet and record each change; a change outside the limits must be referred to the technical team and recorded on the Quality Nonconformance Register.

6.Handover to the operator

Brief the operator on the job card, the in-process checks and their frequency, the regrind percentage, the packing method and any special hazards of the tool. Record the die change time and the first-off approval on the job card and update the tool register with the run start.