01 | Why the same nominal size may not fit
Rim diameter, curl thickness, material and forming tolerance all influence lid closure. The same named size from two factories may use different tooling.
02 | Use actual samples, not dimensions alone
Obtain the target cup and lid, record both references and test the physical set before bulk release.
- Force needed to close
- Even engagement around the rim
- Opening performance
- Lifting or distortion at the lid edge
03 | Test under the real service condition
Fill with the intended drink at the real temperature, then check standing, lifting, tilting and short movement. Delivery use should include the intended bag or carrier.
04 | Record the approved pairing
Save cup and lid references, sample date, test condition and approver so repeat orders begin from the same confirmed set.
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