If equipment is unused for long periods of time, a number of things can happen that will cause trouble during restart. Here are just a few cautionary examples:
- pneumatic and hydraulic filters and other parts of the system can be contaminated with water;
- pneumatic and hydraulic valves can stick in one position. This is a serious fault in a moulding machine, as all valves have to work in a particular order. If one doesn’t, the whole machine can be out of action;
- the AMC (Automatic Mould Conveyor), SBC (Synchronized Belt Conveyor) and other moving belts with mechanical parts can rust and seize up after a long lay-off. A dry run of this equipment is recommended before trying to properly restart production;
- old sand stuck inside the moulding machine chamber and on cope and drag plates (for MATCH machines) is very common and can cause quality issues. Make sure you check that the vents in the moulding chamber are clear and take off the chamber access plates to do this properly.
- sand dries out so will have to be mixed afresh, as per your normal weekly start-up;
- with shot blast machines, corroded shot, dust and abrasive left in the machine can form solid clumps that, if not cleared before start-up, can destroy the machine as well as posing a serious health and safety risk.
If the shut-down was carried out in a hurry (by simply switching the machines off), these issues are more likely to occur. Therefore, even more rigorous inspection and cleaning will be needed, for example to remove stuck-on sand.
What to check: Moulding Lines
First and most important of all: check all safety equipment is working correctly: emergency stop buttons, light curtains, compressed air safety valves, etc.
- Ensure you have all the tools you need.
- Consider your scope of work;for restart: do you just want to start up again like on a Monday morning or are you treating this as a summer shutdown and an opportunity to plan in overhauls and upgrades
- Run through the start-up and service checklists in your DISA machine manuals. Consider booking a dedicated DISA engineer to guide you through this and check additional areas.
- Start at one end of the line and methodically go through to the other end.
- Start checks at least 2 days before scheduled production start (but preferably a lot earlier than that). The two days minimum is based on one day for checks and one day to resolve any issues
What to check: blast equipment
The following checks cover the biggest areas of concern when restarting shot blast equipment after a longer production break but contact the Wheelabrator team for a more detailed list and expert advice.
- check the movement of each blast wheel by moving it by hand, it should turn easily;
- remove condensation from pneumatic systems and clear tubing with dry pressurised air;
- check and, if needed, adjust the tension of the belt on the bucket elevator
- check abrasive quality, remove any clumps
- check abrasive levels and refill as needed
- test all drives by operating them manually
- check the PLC, particularly for loss of blast programmes due to empty batteries
At DISA, we work closely with the Wheelabrator team and can cover your shot-blast equipment (Wheelabrator or not) as part of our re-start package with you.