Startup And Changeover Checklists For Mills, Tumblers And Catalyst Support

Clean startups and smooth changeovers protect quality, time, and equipment. With industrial milling media, you set the tone from minute one by verifying basics before you hit go. This guide gives practical checklists that keep your team aligned across mills, finishing bowls, and reactor packs. Use them to shorten ramp time, avoid rework, and hold a steady baseline.

For mills, consider the charge and the machine to be one system. Check the size mix, moisture, and cleanliness before a new lot of grinding media enters the chamber. Check liners, lifters, and discharge for loose fasteners and wear that could release flakes. Check mill speed, water addition, and classification set points. Document the baseline power draw and noise so you can track drift in the first fifteen minutes.

In finishing, a clean bowl and a matched mix make the difference. Check that tumbling media size and shape suit the smallest features on the parts you plan to run. Check compound level, water quality, and drains for clear flow. Set the media to parts ratio and run a short empty motion test to confirm stroke and amplitude. Load gently and avoid stacking that can bruise edges.

For reactors, flow and heat depend on a stable pack with even distribution. Build and level the catalyst bed in thin lifts and don’t walk on the surface. Check support screens, hold downs, and distributors for damage or debris. Check the internals are clean and dry before loading. Log each lift and photograph the surface so the next shift can match your work.

To produce a high-brightness finish, many shops run stainless steel tumbling media, either pins or balls. Rinse new batches to remove dust before first use, then run a short passivation cycle. Test for magnetism and cull any lot that clings to a small magnet. Keep chloride levels low in the compound and dry parts quickly to prevent stains and rust.

Milling Startup Checklist

The verification chamber is clean and free of previous products. Sieve a small sample of the incoming feed to check top size and distribution. Pre wet or pre heat if your process requires to stabilize viscosity. Set water or solvent flow and check classifier setpoints match recipe. Start at low speed, then ramp to target watching power, sound and vibration. Pull timed sample at five minutes and check size against baseline

Drain and flush the circuit until discharge runs clear. Clean the feed hopper, conveyor, tramp magnets, and transfer hoses. Inspect cyclones or screens and empty underflow pans. Weigh the retained charge and record the value to maintain accurate inventory. Load the next lot. Update the batch sheet to reflect the new product lot ID and target settings. Reset interlocks and alarms reflecting the new product.

Start clean. Wipe the bowl walls, dividers, and drains until they look and feel clear. Sludge scratches parts and dulls the cut, so give it an extra minute. Lay out a few parts and look for thin edges, small holes, and pockets that might trap small shapes. Set your media to parts ratio, check fill height, and watch the motion. Prime the compound line until flow is steady, then check pH and water hardness. Do a short empty run to confirm a smooth stroke and a steady hum. Load gently, start with a short cycle, and check for lodged pieces and any surface haze before you commit.

Think clean to clean. Dump the load and screen out broken shapes and fines so they do not carry forward. Rinse the bowl, hoses, and compound tank until the water runs clear. Swap or clean filters on your set schedule and write it down so the next shift sees it. Charge a dedicated burnish mix and keep abrasive sets in their own bins to prevent cross contamination. Run two scrap coupons to confirm the finish and rinse. Move to production only when the result matches your standard.

Reactor Startup Checklist

Give the vessel a slow, careful look. Check for dust, moisture, and any loose hardware that could travel. Make sure screens, support rings, and distributors are clean, level, and fully seated. Load support layers in thin lifts and level each one with a straight edge. Log bucket counts per lift so the next shift can match your work. Seal the vessel and run a gentle leak test at low flow. Bring up flow and temperature slowly while you watch the pressure profile for a clean, even shape.

Unload spent support into clean totes and keep each layer separate. Reuse only if your spec allows it, and only after a good screen and wash. Inspect for cracks and chips and toss anything suspect. Vacuum the vessel, wipe it down, and check every corner for debris. Reinstall internals and make sure hole patterns and screens are open and aligned. Rebuild the pack with care and document each lift with photos and sign offs so the record is clear.

Verification In The First Hour

Agree on what good looks like before you start. In milling, compare power draw to your baseline and check product size on a timed sample. In finishing, measure brightness or Ra on a known coupon and compare it to the last good run. In reactors, log pressure drop at a fixed flow and watch temperature spread across zones. If anything drifts, pause, adjust one thing, and check again. Small course corrections now save a long recovery later.

Keep a small kit at each asset so checks are quick. Stock a sieve stack, a handheld magnet, pH strips, a thermometer, a flashlight, and a camera. Post a laminated card on each machine with the steps in order. Use colored tags to mark inspection points and dates so status is obvious at a glance. Train everyone to record lot numbers, settings, and first hour readings the same way every time. Simple and visible beats are perfect and forgotten.

Common Pitfalls To Avoid

Skipping a rinse between products creates carryover that lingers and shows up as rework. Mixing old and new charge without a sieve shifts the size mix and slows the cut. Ignoring water quality in finishing invites haze and poor rinse. Rushing a reactor reload without careful leveling leads to channeling and pressure spikes. Small habits at startup prevent long days of chasing problems.

After each changeover, hold a short huddle with the crew. Note what slowed you down and which checks caught issues early. Turn those notes into one update on the checklist or the machine card. Compare first pass yield and time to steady state across recent runs. Keep the list lean and land one improvement each week. Progress should feel steady and simple.

Wrap

Pick one line today and run these steps. Gather the tools, do a clean startup, and capture first hour data. Share the result with the team and lock one improvement for the next run. Small, consistent habits keep quality steady and schedules on track.