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Scantech biax film measurement and control

Biax Film Thickness Measurement & Stretch Profile Control

Measure film before and after stretching to understand how its thickness changes through the line. Scantech combines cross-web low-energy X-ray measurement with stretch-profile analysis, automatic mapping and optional BC3 die control. One- or two-scanner configurations are available for BOPP, BOPET, BOPE, BOPA and other biaxially oriented films.

Authorized Scantech sales and applications support for Western North America. Gauge Advisor sells and quotes Scantech biax-film gauging systems. We define the scanner positions, edge-measurement requirements and any control or TREX reporting scope for Scantech’s technical review.

Cast and final-film stations High-fidelity tenter edges Stretch-aware mapping Optional BC3 control
Review my biax line Explore Scantech web gauging

Choose the configuration for your line: The scanner count, measurement output and control strategy depend on the film structure, stretching sequence, web width and path, edge requirements, and the adjustments the die hardware can make.

Scantech HF3 heavy-frame scanner for wide biax film measurement
Wide-web Scantech X-ray systemULO3, HF3 or SHF3 selected around the actual station
One scanner measures a profile. Two stations show how it changes through stretching.
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When a final-film profile is not enough

The production problem is often locating where variation entered the process

A biaxial line stretches film along its length, called machine-direction orientation (MDO), and across its width, called transverse-direction orientation (TDO). A final profile can show the result without proving whether the variation began at casting, developed through orientation or came from unstable edge behavior.

CAST

Cast-sheet variation is hidden later

The final film is wider and thinner, so an upstream die pattern no longer aligns one-to-one with downstream positions.

TDO

Stretch response changes the profile

Stretching along and across the line can amplify, redistribute or introduce variation that a final-film scanner sees only after stretching.

EDGE

Tenter-grip shape affects stability

The edge must remain thick and correctly shaped enough for the clips to grip without turning the trim region into an unmonitored blind spot.

MAP

Die corrections need a reliable map

Automatic control must account for measurement positions, material travel time, stretch ratios, the edges included in the calculation, and how each die adjustment affects the film.

Pre-stretch and post-stretch measurement

Two scanners connect the incoming cast-sheet profile with the final film

Scantech strongly recommends two scanners on many biax lines: one at the cast section and one at the film section. Relating the two profiles improves die mapping, control stability and insight into how the orientation process is performing.

01

Extrusion die

The cast sheet begins with the current die-lip and actuator profile.

02

Cast scanner

Scanner one measures the incoming pre-stretch sheet profile.

03

MDO stage

Machine-direction stretching changes thickness and material coordinates.

04

TDO and tenter

Transverse stretching expands the web and forms the final edge geometry.

05

Film scanner

Scanner two measures the post-stretch final-film and edge profiles.

06

Map, diagnose or optionally regulate

Stretch-aware logic supports diagnosis, operator guidance or qualified upstream control.

One material path, two measurement views

Mass conservation and stretch-profile logic make the profiles comparable

The relationship is not simple point-to-point matching. The project must account for scanner registration, machine- and transverse-direction stretch, width change, trim and clip-zone exclusions, line delay and the accepted measurement model before a final-film deviation is assigned to an upstream die zone.

Hundredsof biax process-line installations reported by Scantech
12.5 mwidest supplied biax scanner reported on a BOPP line
3 familiesULO3, HF3 and SHF3 selected around station requirements
Review my scanner stations
Why edge fidelity matters

Low-energy X-ray preserves the edge detail the tenter process depends on

Scantech links its X-ray measurement footprint and sensor speed to high-fidelity edge measurement. This is especially relevant where tenter clips require a thicker, correctly shaped region of film or sheet for reliable clamping.

More than center-web uniformity

Measure the grip-band shape instead of treating every edge point as trim

On BOPET and other demanding biax processes, the edge profile can influence clip engagement, clip-outs, film breaks and usable width. A well-resolved edge signal gives operators and control logic a clearer view of the transition between the product profile, tenter-grip region and excluded trim.

Confirm edge performance on your line: Edge performance depends on the complete measurement system: the area sensed, sensor response, scanner position, sampling and edge-processing settings. Confirm the required edge detail with the proposed configuration and film.

High-fidelity edge profileResolve the steep transition adjacent to the tenter-clip grip region.
Pre- and post-stretch contextCompare the cast-sheet edge with the edge created through orientation.
Stable total-film signalMeasure total basis weight or calibrated thickness across optically changing films.
Electrically generated sourceAvoid sealed-isotope half-life and end-of-life source disposal.
Profile input

Total basis weight or calibrated thickness

Define whether production accepts an X-ray mass response, a calibrated thickness result or another qualified output.

Density, fillers, cavitation, layers and formulation changes still belong in the calibration review.
Edge definition

Grip band, edge bead, trim and usable web

Agree which edge regions are measured, trended, controlled, alarmed or excluded.

One universal edge cutoff can hide the condition the line is trying to manage.
Spatial performance

Footprint, sampling and scanner speed

Effective resolution depends on the full measurement and motion system, not sample spacing alone.

Review line speed, scan time, web flutter and the smallest profile feature that must remain visible.
Recipe qualification

Match the displayed result to the accepted result

Use Scantech low-energy X-ray where total-film profile, edge fidelity and non-isotope operation match the production objective.

If a specific layer or constituent is the true target, define that requirement before selecting the measurement model.

Need the physics-level comparison? Review X-Ray Transmission Web Gauging for measurement boundaries before treating any sensor label as the complete specification.

Scanner family by span and station

ULO3, HF3 and SHF3 cover compact through super-wide biax lines

The published ranges overlap. Width screens the portfolio, but final selection also depends on passline, foundation, opening, service access, environment, sensor count and the mechanical demands at each measurement station.

Scantech ULO3 ultra-light O-frame scanner
Narrower biax stations

ULO3

Ultra-light O-frame starting point for cast or film sections where a compact full-pass-through frame fits the line.

Published product width
500 to 3,500 mm
Selection review
Opening, passline and access
Scantech HF3 heavy-frame scanner
Mid-width through very wide lines

HF3

Heavy-frame design for wider biax stations requiring greater span, stiffness and structural capacity.

Published product width
500 to 11,500 mm
Selection review
Span, stiffness and foundation
Scantech SHF3 super-heavy frame platform shown with optional visual inspection
The widest biax installations

SHF3

Super-heavy frame for very wide measurement stations. The image shows the SHF3 platform with optional integrated visual inspection; dimensional gauging does not require the VI package.

Standard published range
500 to 13,500 mm
Extended configurations
Application review up to 15 m

The two stations do not need identical frames. A narrower cast section may fit ULO3 or HF3 while the expanded final film requires HF3 or SHF3. Select each station independently around its measured width, passline, opening, access and structural requirements.

Scantech Bolt Controller 3 BC3 hardware cabinet
BC3 is optional control hardware. A scanner alone does not automatically correct the die.
From final-film error to upstream action

Stretch-aware mapping gives BC3 a more reliable correction target

FlexScan/APC can relate the measured profiles to the upstream automatic die, apply the qualified control model and coordinate corrections through Scantech Bolt Controller 3 or another approved actuator interface. Scantech publishes TDO stretch profile, mass conservation, melt-flow modeling and cascade control as biax capabilities; the model and control-loop design are engineered for each application.

Automatic mappingRegister measured film positions to qualified upstream die zones.
TDO stretch profileApply a qualified biax-specific profile model to the transverse stretch section.
Mass conservationUse Scantech's published mass-conservation capability within the engineered model.
Cascade controlCoordinate qualified measurement and control loops within the engineered system.
BC3 through 360 boltsFinal channels, power, cabinet and wiring follow written project review.
Heater-failure detectionDetect and flag die-bolt heater failures for action.

Die coordination: Gauge Advisor has worked with projects involving Cloeren, MAAG, Nordson EDI, maku, JCTIMES and other equipment suppliers. Final compatibility is confirmed from the exact die, actuators, electrical design, controls and drawings.

Explore automatic profile control
Live decisions and completed-roll evidence

FlexScan displays the measurements. TREX retrieves production reports.

Operators need the cast profile, final-film profile, stretch behavior, edge rules and control status to remain distinguishable. Production and quality teams then need a configured history that can be retrieved after the roll is complete.

Scantech FlexScan profile and automatic-control screen
FlexScan live profile and control

Show measurement, position mapping and correction separately

Configure the operator view around profiles, targets, edge exclusions, mapped zones, trends, alarms, control mode and the response following each qualified correction.

Scantech TREX production explorer and roll-report interface
Optional TREX production-report archive

Retrieve completed production reports by meaningful tags

When TREX is included, it can retrieve, sort, categorize and collate archived production reports using configured tags. Report contents, identifiers, retention, user access and plant-interface requirements are defined in the project scope.

Cast-sheet profile
Final-film profile
TDO and edge profile
Mapping and control status
TREX roll history

Plant connectivity: Scantech publishes OPC UA as standard for the biax system design. Final tag ownership, PLC logic, cybersecurity, retention, remote access and higher-level interfaces remain project-specific.

Explore FLEXSCAN software & TREX reporting
Inputs for a useful system review

Review the full line from cast sheet to finished film

Review the line drawing, stretching sequence, required measurement, edge criteria, die adjustment range and reporting needs together when planning two scanner stations.

01 / Product

Film structure and accepted result

Define what the system must measure and what production releases.

  • BOPP, BOPET, BOPE, BOPA or other film
  • Layers, resin, fillers, cavitation and density
  • Nominal range and reference method
02 / Stretch

MDO and TDO process

Describe how material coordinates change through the line.

  • Stretch sequence and nominal ratios
  • Widths before and after each stage
  • Speed, delay, trim and grade changes
03 / Stations

Cast and film scanner locations

Confirm each web can be measured safely and repeatably.

  • Passline, opening and measured width
  • Flutter, temperature and environment
  • Foundation, access and service clearance
04 / Edges

Tenter grip and usable-width rules

Separate the regions instead of applying one generic edge cutoff.

  • Clip band and edge-bead geometry
  • Trim location and usable product width
  • Alarm, trend, map and exclusion rules
05 / Control

Die hardware and adjustment range

Document what hardware can make the correction.

  • Die supplier, model and drawing
  • Bolt count, spacing and actuator type
  • Existing PLC, controller and interlocks
06 / Evidence

Software and acceptance plan

Agree how operators and quality teams will use the result.

  • FlexScan views, modes and alarms
  • TREX tags, reports and retention
  • FAT, SAT, tuning and training
What the system is intended to improve

Turn the final-film profile into faster diagnosis and more confident control

Scantech reports that two-scanner biax systems can support more reliable mapping, faster and more stable control and better process insight. Actual results depend on the starting line, film recipe, measurement model, die condition and commissioning.

◎

More reliable die mapping

Relate the expanded final-film profile to the correct upstream material and control zones.

↘

Reach the film specification sooner

Use qualified mapping and cascade feedback instead of repeated manual interpretation.

EDGE

Better tenter-edge visibility

Monitor the grip-band shape and edge behavior associated with clip stability and usable width.

▣

Clearer production records

Connect live profiles and control behavior with configured TREX history and roll reporting.

Basis weight and physical thickness are not always interchangeableDensity, filler, foam, cavitation and layer changes can change the relationship. Specify the accepted measurement result.

Edge data needs a declared purposeGrip band, edge bead, trim and saleable width may need different trend, alarm, mapping and exclusion rules.

Automatic correction needs compatible die hardwareAutomatic correction still requires a compatible die, sufficient response, safe modes and commissioned control limits.

Estimate material and scrap savings
Biax film gauging FAQ

Common biax measurement questions

Why use scanners before and after stretching on a biax film line?
The cast-section scanner establishes the incoming sheet profile before orientation. The film-section scanner measures the final profile after stretching. Relating those measurements improves die mapping, helps separate cast-sheet variation from MDO or TDO response and gives the control system a more reliable basis for correction.
Does every BOPP or BOPET line require two scanners?
No. Scantech strongly recommends two scanners for many biax applications because they provide more complete mapping and process insight, but the final station count depends on the measurement objective, line layout, existing equipment, budget and whether upstream diagnosis or closed-loop control is required.
Why is low-energy X-ray valuable at the tenter edges?
Scantech associates its X-ray measurement footprint and sensor speed with high-fidelity edge measurement. This can preserve detail in the thicker, shaped region used by tenter clips, helping production monitor conditions associated with clip-outs, film breaks and lost usable width. Final performance still depends on the complete sensor, scanner, sampling and edge-processing configuration.
Does X-ray measure basis weight or true physical thickness?
X-ray transmission directly responds to material attenuation. A system may display basis weight or a calibrated thickness result depending on the product model and approved calibration. Density, fillers, cavitation and layer changes can affect that relationship, so the accepted measurement result should be defined before quotation.
How do ULO3, HF3 and SHF3 differ?
ULO3 is the ultra-light O-frame published for product widths from 500 to 3,500 mm. HF3 is the heavy-frame family published from 500 to 11,500 mm. SHF3 has a standard published range from 500 to 13,500 mm, with extended configurations advertised up to 15 m subject to application review. These ranges overlap; measured width, passline, station geometry, access, environment and sensor package determine the actual frame.
Can the system automatically correct the final-film profile?
Potentially. FlexScan/APC can map qualified final-film variation back to the upstream die, and Scantech Bolt Controller 3 can regulate compatible thermal bolts. Supported motorized or robotic actuators require their approved interface. Automatic correction depends on die condition, process delay, mapping quality, actuator authority, safe modes and commissioning.
What products can Scantech measure on biax lines?
Scantech reports systems on hundreds of biax process lines, including BOPP, BOPET, BOPE, BOPA, BOPETG, BOPI, BOPVC and BOPS. Each film structure, thickness range, filler level and accepted result still requires application review and calibration.
Where do FlexScan and TREX fit?
FlexScan provides the live measurement, profiles, mapping, alarms, trends and control interface. When included, TREX retrieves, sorts, categorizes and collates archived production reports using configured tags. Report content, identifiers, retention, users and plant interfaces are defined in the project quotation.
Is visual defect inspection included with SHF3?
Not automatically. SHF3 is the super-heavy gauging frame. SHF3 VI is a separate configuration that adds cameras inside the frame beams for qualified surface inspection. Defect size, contrast, web speed, lighting, coverage and data requirements must be reviewed separately.
Can Scantech biax gauging be retrofitted to an existing line?
Potentially. The review must confirm physical scanner locations, measured widths, passlines, access, utilities, line speed, existing sensors and controls, die and actuators, I/O, networks, edge rules and acceptance testing. A line drawing and current profiles are the best starting inputs.
Scantech application review and quotation coordination

Start with the line drawing, stretch sequence and the profile you need to explain

Share the line drawing, film construction, stretching sequence and current thickness profiles. Gauge Advisor will help define the measurement, control and reporting requirements and coordinate Scantech’s technical review and quotation.

Equipment project inquiries welcome worldwide. Gauge Advisor reviews your application and coordinates the next step with Scantech.

Request a biax measurement review Review the film & sheet applications
  • Line drawing and stretch sequence
  • Cast and final measured widths
  • Current profiles and edge examples
  • Die, actuators and existing controls
  • FlexScan, TREX and acceptance needs