10 Things to Pay Attention to When You Experience Longer Than Normal Breaks Between Production Runs

When a machining center has been in production continuously and then shut down for an extended period of time, there are several operations to perform and check before placing the machine back into full production.

Learn what you need to pay attention to when your experience breaks:

1. Before starting up the machine, inspect all of the cover wipers, including the operator’s door, for damage and replace if needed.
   
   
2. Check the through tool coolant pin seal for wear. Replace the pin if needed or if the normal maintenance schedule says it’s ready to be replaced.
   
   
3. Inspect the through tool coolant filter bags or filters for excessive contamination and normal wear and tear. Replace if needed.
   
   
4. Check the fluid levels in the hydraulic unit, chiller unit and spindle lubrication unit. Replenish if needed and consider replacing the filters and changing the fluids in both units if it’s been a long time since the fluids have been changed in the hydraulic and chiller units.
   
   
5. If there is a tool in the spindle since the machine shut down, remove the tool by hand using the clamp/unclamp manual function. Check to make sure the spindle is clean as well as the tool taper and re-install the tool.
   
   
6. If there is no tool in the spindle, cycle the spindle tool clamp/unclamp function by pressing the tool change cycle button and unclamping. Repeat 5 times to exercise the unclamp system before performing a tool change using the ATC system.
   
   
7. Move all axes of the machine to their full stroke plus and minus limits at a slow federate one axis at a time to allow the ballscrews and linear guides to be wiped and allow each component to gain a coat of lube oil.
   
   
8. When the machine has been setting up for a few days, run the spindle at 100 RPMs for 10 minutes, then perform the warm-up procedure on the machine’s operators side placard. If the machine has no warm-up procedure, run the spindle at 100 RPMs for 10 minutes, increase to 500 RPMs for 10 minutes, and then increase another 500 RPMs for 10 minutes. Repeat until the spindle reaches full speed and allow it to run at full speed for 15 minutes. This allows the spindle to settle in from a dormant state and allows the bearings to become lubricated with fresh oil.
   
   
9. Remove the old coolant, clean out the coolant tank and replace with new coolant. This removes any build up within the coolant tank and ensures that any sludge is not cycled in a heavy concentration during normal production.
   
   
10. Cycle the ATC through a complete cycle by one step advance in manual mode. This allows the ATC to cycle at a slower pace than in automatic and allows it to churn up lubrication of the cam box and give the operator a chance to perform a function test, ensuring there are no underlying conditions.

Performing all the above steps will help ensure a smooth startup after a machine has been sitting for a long period of time in a static state. It also will allow for a pre-start inspection to check for any issues that may need to be addressed.

Special thanks to Tim Chaney, Principal Engineer, Okuma America Corporation, for providing this article