Repeated Dispensing with Valveless Pumps: Displacement, Start-Stop Behavior and Nozzle Droplets

01Locate the source, drive and receiving position for this task

Define dose volume, dose count, first and last doses, retained volume and recovery after refill. Follow the diagram to confirm liquid contact, pressure and destination at each position before assigning drive and connection roles.

02Compare displacement options against dose and cycle time

Estimate rotation and speed ranges from dose and cycle time, comparing minimum and maximum task volumes. Actual backpressure, viscosity and nozzle action may change output. Include startup and stopping states.

03Compare product options against task requirements

The following candidate options match this page's responsibilities. Compare them against the operating conditions described, then check capacity, materials and interfaces on the product pages. Card images show representative configurations; suitability must still be confirmed at actual operating points and by application results.

04Coordinate nozzle state with vessel timing

After priming, dispense to the vessel cycle, recording nozzle droplets, remaining liquid and bottle-change timing. Check the first dose after extended standby separately. After interruption, retain records of vessels already filled.

Action records should link commands, valve or interface states and actual received results. When raw material, container or sample identity changes, reconfirm shared paths and conditions permitting the next step. Completion of drive movement alone does not replace task acceptance.

05Measure startup doses and successive doses separately

Measure individual doses, first/last doses and blanks after high/low concentration changes using actual reagents. Stable continuous output does not directly establish stable start/stop dispensing.

Record test medium, configuration, installed path and operating sequence; present routine operating points and boundary results separately. Calculations support design discussions, component documentation checks models, and installed measurements confirm the actual task.

06After an abnormality or maintenance, first identify which segment needs recovery

Empty sources, bubbles, nozzle droplets and backpressure changes can affect first or last doses. Stop affected steps, validate recovery after priming and avoid duplicate dispensing.

Retain current source, container identity, completed actions, valve or interface state and actual receiving information. Use the table to locate the stage that changed before deciding to retry, continue or restart. After recovery, recheck the relevant operating point before returning an uncertain action to the automatic cycle.

07Continue with tasks on the same branch

References

Related guides

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