A suction cup is a process interface, not merely a rubber spare. Lip shape, cup profile, material hardness, surface condition and mounting compliance affect whether a blank is picked cleanly, released on time and left without marks. The best choice depends on the actual coated paper, blank geometry and machine motion.
Before changing the cup, confirm that vacuum supply, tubing, valves, ejectors, filters, timing and target presentation are stable. A new cup cannot correct a restricted line or a blank that never reaches the pickup datum.
Decision matrix
| Selection factor | Evidence | Decision question |
|---|---|---|
| Paper surface | Coating, texture, dust, porosity and approved samples | Can the lip make a repeatable seal without marking? |
| Profile | Flat, deep or bellows geometry; lip diameter | Is compliance needed for height or angle variation? |
| Material | Supplier resistance data and application conditions | Will the material tolerate heat, wear, oil and cleaning exposure? |
| Connection | Thread, nipple, holder and anti-rotation arrangement | Will it fit without adapters that change height or flow? |
| Motion | Acceleration, hold time and release requirement | Does it retain and release the blank through the real cycle? |
Separate sealing from lifting force
Inspect the contact print and leak behavior with the actual blank. A lip may seal well on a smooth coated region but leak across an embossed area, edge curl or printed texture. Larger diameter changes the contact area and may interfere with neighboring tooling.
Vacuum level at the generator does not prove usable vacuum at the cup. Measure or compare at the closest practical point and inspect the full flow path.
Choose profile for the pickup geometry
A flat profile is suitable only when the surface and approach are sufficiently consistent. Bellows can add compliance and limited lifting motion, but also change stiffness, collapse behavior and release timing. Do not add bellows merely to compensate for poor mechanical alignment.
Match holder height, approach angle and compression. Excess compression rolls the lip, accelerates wear and may mark the blank; insufficient compression can leave a leak.
Choose material from declared properties
Schmalz identifies abrasion, oil exposure, temperature and food-safety requirements as material-selection factors. Obtain the exact supplier data for the proposed cup rather than assigning properties from color alone.
If a food-contact claim is required, request documentation for the exact material and intended use. Do not describe every silicone or colored suction cup as food compliant. Also check interaction with the approved cleaning method.
Run a structured pickup trial
Use a labeled material lot and record single-pick success, double-pick events, drop location, release delay, visible marks and lip wear. Test at setup speed and controlled production speed with guards restored.
Change one factor at a time. If the holder, vacuum timing and suction cup all change together, the trial cannot show which change solved or introduced the problem.
Define the spare by function and evidence
Store manufacturer, part number, material, profile, diameter, connection, approved station and trial date. Keep an unopened reference spare and inspect stored elastomers for age or deformation before use.
Use the linked vacuum troubleshooting guide when losses appear across several stations. For machine-specific replacement review, send paper samples, cup photos and the installed pickup assembly details.
Technical references
- Schmalz suction cup material overview — used for the general component principle; the installed machine documentation remains controlling.
Related machine and guide
Review the HN-180 high-speed paper cup machine for machine context, then use the vacuum pickup troubleshooting guide for the adjacent maintenance or process check. Browse all Buyer Guides when building a wider project checklist.
Frequently asked questions
Is a larger suction cup always stronger?
No. It changes contact area, fit, flow and release behavior and may interfere with the blank or tooling.
Can color identify suction cup material?
Not reliably across suppliers. Use the exact part number and supplier material data.
Why does a new cup still drop blanks?
Check supply, restrictions, timing, holder alignment, blank presentation and surface condition before blaming the elastomer.
How should a replacement be approved?
Use controlled trials with the actual paper and cycle, record pickup and release results, and keep the approved part specification.
Review your machine configuration with HANNAI
Send the machine model, cup or material drawings, component labels, photos and a description of the required result. We will clarify which details must be confirmed before a quotation or technical recommendation.