Presentation on theme: "Seal-Scan Non-Destructive Inspection Technology for Retort Pouches Tony Stauffer Packaging Technologies & Inspection Tuckahoe, New York PTI Inspection."— Presentation transcript:
Seal-Scan Non-Destructive Inspection Technology for Retort Pouches Tony Stauffer Packaging Technologies & Inspection Tuckahoe, New York PTI Inspection Systems:
Seal-Scan Only Seal Inspection system that is: Non-destructive Non-invasive Non-contact
Applications of Seal-Scan Ultrasound Inspection Analyzes seal quality of pouches and flexible packages Characterizes bonded materials Works with all materials: film, alu, paper, or composite Process control Quality control Research and development
Seal-Scan Produces a single linear scan in less than 1 second Digital pouch seal image in less than one minute Images and characterizes bonded materials Helps in process optimization
Seal-Scan Principle of Through Transmission SEAL TransmitterReceiver Ultrasonic Signal Pouch seal or package material is placed between ultrasonic transmitter and receiver
Ultrasonic Signal Ultrasonic waves propagate through single or multiple layers of well bonded materials. Transition through different mediums causes reflection of sound waves and reduces/eliminates signal strength.
Seal-Scan Technology Ultrasonic signal is transmitted along the X-axis through seal and signal is recorded. Signal measurement correlates to color gauge, creating high resolution image of seal structure and quality.
Seal-Scan Signal Scale Opto Acoustic Image The colored gauge represents the scan signal measurement. Pink is low signal, green is normal signal (good seal), purple is high signal. Total 6000 grades of color are used.
Scanning Modes C-Scan produces an Opto-Acoustic image and summary data L-Scan produces a graph of the signal and summary data.
Pass – Fail Criteria and Data Integrity Pass – Fail limits are set for the average, minimum, maximum, and standard deviation of the signal measurements, All results are recorded using the systems data log.
Seal-Scan 525 Offline Analytical Equipment
C-Scan Analytical Tools 10 mm 135 mm 128 mm 6 mm 3.5 mm C-Scan window statistics Modified L-Scan
C-Scan Analytical Tools C-Scan statistics of moving window 10 mm 135 mm 16 mm 6 mm 3.5 mm
Optimizing the Sealing Process Variation decreases with increasing temperature. Optimal Sealing Temperature Seal-Scan serves as an analytical tool to determine optimal sealing conditions; e.g. temperature, dwell time, etc.
105 C HDPE 105 C HDPE 105 C HDPE 105 C HDPE 105 C HDPE 128 C HDPE 128 C HDPE 128 C HDPE 128 C HDPE 128 C HDPE 108 C TYVEK 108 C TYVEK 108 C TYVEK 108 C TYVEK 108 C TYVEK 134 C TYVEK 134 C TYVEK 134 C TYVEK 134 C TYVEK 134 C TYVEK Material Analysis HDPE exhibits better sealing uniformity and quality at higher temperatures. TYVEK ® exhibited weaker bonding at higher temperatures.
Background Pouches with peelable seals were tested. Peel strength test was performed on specific area of seal sample, approximately one-inch. Seal-Scan C-Scan mode analysis of entire length of seal was performed. Results confirm direct correlation of both methods. Seal-Scan and Peel Strength Testing
The Standard Deviation of the ultrasound signal correlates to the peel strength of a peelable seal. Seals with more variation in the quality of a sealed area will be easier to peel than a seal area that is uniform. If a seal has strong points of bonding but exhibits high variation, the peel strength of the seal will be less.
Good Seal Profile(Film-Pouch) C-Scan Seal width profile L-Scan Seal Width Data, mm L-Scan Statistics, % Signal Value Avg Min StD AvgMinMaxStD Seal Quality Histogram Test results to be compared against Pass-Fail reference values.
Defective Seal Profile (Alu-Pouch Channel Leak) Avg Min StD AvgMinMaxStD C-Scan Seal width profile L-Scan Seal Quality Histogram Seal Width Data, mm L-Scan Statistics, % Signal Value Low average and minimum, with high standard deviation.
Case Study Heinz Douarnenex, Fr Defect Profile - 30,000 pouches were visually inspected 100% Defect typeCommentNumber detected Reject Rate LeakCritical 3.01% Corner channelMajor or critical 4.01% WrinkleDepends on height 8.03% InclusionDepends on height 4.01% Air bubblesDepends on size 19.06% WavesUsually minor 12.04% BlisterMinor 86.29% FoldMinor 11.04% Total defects %
Case Study Heinz Douarnenex, Fr Typical Defects LeakCritical Corner Channel Critical Wrinkle Critical (may vary) Inclusion Minor Critical
Case Study Heinz Douarnenex, Fr Typical Defects Air Bubbles Critical Waves Critical Minor Critical
PTI-550 Online Pouch Inspection Pouches go onto Seal-Scan from pouch machine at 60-70/Minute
PTI-550 Online Pouch Inspection 1. Pouches are dropped into a special conveyor 2. Pass through PTI Seal-Scan Ultrasonic-head 3. Accepted or rejected
PTI-550 Online Pouch Inspection Pouch Seal is guided through the Seal-Scan Head
PTI-550 Online Pouch Inspection Seal-Scan Head with Operator interface
Channel Description An area of non-bonding across the seal that will generally leak Cause Sealing bar settings were not correctly set (temperature, pressure and/or dwell time.) Contaminants may be present during seal formation.
Compressed Seal Description Any separation of laminates in seal area. Material bond strength is questionable in defect area. Visual evidence of overheating such as bubbles. Cause Sealing bars were too hot during seal formation. Material bond strength is inadequate.
Contamination Description Foreign material is trapped in seal. Retort pouches will have noticeable raised areas in seal where sealing bar sealed over contamination. Cause Seal area was contaminated during filling stage.
Crooked Seal Description A seal that is not parallel to the cut edge of the pouch Cause Pouch was misaligned in the sealing jaws.
Cut Description A breach of all layers of the laminate, where the hermetic integrity of the package was compromised. Cause Equipment damage or scrap between laminate plies during formation. Pouch contacted sharp edges of other pouches or equipment. Pouches were abused during online or post-process handling.
Delamination Description Separation of laminated materials – can occur before or after retort process. Delaminations ultimately affect seal strength through life cycle/distribution process. Cause If occurring at the seal, bars were too hot during seal formation. If during retort process, residual air in the pouch was not controlled to eliminate pouch expansion during retorting.
Incomplete Seal Description Seal area does not extend completely across the width of pouch. Cause Pouch was not positioned correctly in sealer and sealing bar.
Narrow Seal Description Container seal area has no margin of safety to accommodate seal creep or wrinkles. Cause Defective sealing bars reduced seal width. Defects that cross seal, seal creep or mechanical separation reduce seal width.
Non-Bonding Seal Description Sealing films fail to weld during sealing process. Defect appears as faint sealing bar impression on retort seals. Application of slight pressure to seal will cause failure. Cause Seal area was contaminated. Sealing bar settings were not correct (pressure/temperature/dwell time).
Wrinkle Description Material fold on one seal surface, caused when one seal surface is longer than the other. Can also be a severe fold over both seal surfaces at sealing time. Cause Sealing surfaces were not flat and parallel or were not tensioned. Various other irregularities in sealing bar or surfaces.
Pouch Inspection Economics One technology useable for all materials Non-Destructive, Non-Invasive No sample preparation, No special Inks, no added variable costs Replaces costly, low efficiency manual Inspection Reduces/eliminates Incubation Saves product & packages Long term quality tracking Integrates into most pouch sealing machines Real Time Process Control - allows immediate corrective action Increases line efficiency Good return on investment You sleep better at night