Paper cup bottom roll preparation starts before the roll reaches the forming machine. A roll can carry the correct material label yet have damaged edges, uneven winding or a slit width that does not match the approved tooling. Treat roll identity, physical condition and feeding performance as separate checks. This guide helps production and purchasing teams prepare evidence for a controlled trial without assuming that one roll specification fits every cup.
Start with the approved bottom-stock specification
Obtain the bottom-paper specification for the actual cup drawing and machine configuration. Confirm the required slit width, paper and coating identity, coated-side orientation, winding direction and reel interface with the machine supplier. These are order-specific requirements; an apparently similar reel is not an approved substitute.
Link each reel to its parent roll and slitting batch. Keep the material supplier's lot reference, conversion date and inspection record together. If the roll label is missing or conflicts with the production order, hold the reel rather than identifying it by appearance. The paper cup material incoming inspection guide explains the material approval step that comes before feeding.
Inspect slitting and winding before loading
Check accessible reel edges for crushed sections, tears, loose layers and visible debris. Compare slit width with the approved specification using the agreed measuring method. Record where measurements were taken so an edge reading is not mistaken for evidence about the entire roll. Ask the converter to provide its width-control records when variation is suspected deeper in the reel.
| Checkpoint | Evidence to collect | Decision before feeding |
|---|---|---|
| Material identity | Lot label and approved specification | Resolve any paper or coating mismatch |
| Slit width and edges | Defined width readings and edge photographs | Hold material outside agreed acceptance criteria |
| Winding condition | Loose layers, damaged core or displaced winding | Obtain a handling or replacement decision |
| Splices | Location and supplier's splice information | Confirm the machine-specific handling procedure |
| Trial feed | Tracking observations and sample references | Release only against the agreed trial result |
Do not repair a damaged core or introduce improvised splices to keep a reel running. The converter and machine supplier should agree on whether the material can be safely used. Photograph the condition before unpacking damage becomes difficult to distinguish from handling damage.
Confirm the feed path through a controlled trial
Loading and threading must follow the machine manual and the site's safe isolation procedure. Qualified personnel should confirm the supported reel mounting, threading path and adjustment method. Never reach into moving feed or punching equipment to correct tracking.
Use an identified roll and the approved cup setup for the trial. Observe whether the paper tracks consistently, whether interruptions correspond to a visible reel defect and whether bottom blanks are produced as intended. Record the point in the reel where the issue first appears. A feed problem and a finished base-seal problem may occur together, but that does not prove they have the same cause.
Keep trial cups for the bottom seal inspection. Check finished-cup results as well as material movement. Document changes one at a time, using authorized procedures, so the next trial can be compared with the original condition.
Release the roll with a usable record
The release record should identify the cup drawing revision, tooling, material lot, reel, checks completed, trial samples and person approving use. Define what happens when a different parent roll, coating or slitting supplier is introduced. An earlier successful reel does not automatically approve a changed supply.
For machine selection, review the HANNAI paper cup machine range alongside your actual bottom-stock requirements. Send an inquiry with the cup drawing, material specification and reel details so the loading and trial requirements can be confirmed for the proposed configuration.
Preserve a mid-reel finding without changing its identity
If tracking changes after part of a reel has been consumed, record the reel reference, remaining condition and the production interval where the symptom first appeared. Compare any visible damage or reported splice information with that timeline. Do not infer that a guide adjustment is wrong simply because the reel fed smoothly at its beginning.
Keep relevant accessible material evidence through the approved handling procedure. Request the converter’s applicable slitting or winding records when the suspected variation cannot be observed safely at the machine. Do not unwind, lift or reach into a moving reel to complete the investigation.
Carry the finding through to finished-cup disposition
Link trial and suspect cups to the reel and production interval. A restored feed path does not establish that all previously formed bottoms meet the product requirement. Apply the agreed base inspection and quality decision to the identified scope, retaining the original finding.
Record whether the next authorized action concerns roll disposition, handling, a component check or a documented setup review. This keeps an apparent material problem from becoming an unsupported machine-fault claim, and prevents a temporary improvement from silently approving an unconfirmed roll specification.
Frequently asked questions
Can one bottom-roll width serve several cup sizes?
Only if the supplier confirms compatibility with their tooling and approved cup specifications. Shared nominal capacity does not establish the same bottom geometry.
Does smooth feeding prove that the bottom seal is acceptable?
No. Feeding, bottom forming and finished-cup sealing need their own checks. Retain trial cups and evaluate them under the agreed inspection plan.
How should an unidentified splice be handled?
Hold the reel until its splice information and handling procedure are confirmed. Record the location and consult the converter and machine supplier.
What should accompany a feeding complaint?
Include reel and parent-roll references, approved slit specification, photographs, the observed interruption point and the trial setup. Preserve a relevant sample where practical.