Scorebend / Opening Force Tester (PCA)

The Scorebend / Opening Force Tester is a microprocessor controlled testing machine for determining both the force required to open a carton from flat and the stiffness of individual box carton creases/flaps. Manufactured by Thwing Albert, both parameters are critical for ensuring the smooth running of carton erection on folding carton packaging lines. A choice of interchangeable load cells enable small corrugated boxes to also be tested.

Coefficient of Friction Opening Force fixture Bending force Fixture
Coefficient of Friction Opening Force Fixture Bending Force Fixture

As the packaging industry depends more and more on high-speed automation, it is essential to understand how carton materials will behave in production. The Score Bend/Opening Force Tester provides vital information for:

  • accurately configuring machinery that controls cartons on form, fill and seal lines
  • analysing carton performance characteristics for development and quality control
  • evaluating the efficiency of cartons during production runs

Determining the conditions required to guarantee the production of cartons within tolerance can increase both production and efficiency and result in less reworking, rejects and down-time.

The Score Bend/Opening Force Tester determines the force required to fold carton stock along a score and the force necessary to open a carton, a particularly important consideration for the evaluation of spring back after bending, which can affect sealing or gluing operations.

The instrument is easy to use, with bending and opening force, measured in grams, appearing on a clear LED panel. The high-quality construction and sophisticated electronics require minimal maintenance and the precision of the instrument makes it ideal for exacting research and development, and durable for the factory floor.

Standards: TAPPI RC-284, PI 110.10

Measures bending and opening force, stiffness of unscored paperboard, residual spring back force, score ratio of scored or unscored paperboard
Opening force fixture Statistics include average, high, low and standard deviation
Pulling unit Measurement capacity up to 10 kg
Saves up to 99 test results Auto-zero and semi-automatic calibration
Constant loading rate Test result and curve data for PC interface
Sample ID capability Automatic stop and return with overload protection
Physical specifications
Software control Dimensions 56 x 41 x 122 cm (W x D x H) Net weight 68 kg
The front panel provides easy access for configuring test parameters including test mode, force and distance units, sample ID and crosshead return. Statistics for peak force, angle, force and distance traps values are automatically calculated and displayed. Test results and curve data can be output via an RS-232 interface for data collection to a PC or parallel printer.
Operating/storage environment
Air temperature 15-25 °C Relative humidity 20-60% (non-condensing)
Pneumatic clamping assembly Bending fixture for measuring the maximum force required to bend a carton sample up to 90° Printer
COF fixture for measuring static and kinetic coefficient of friction Data-acquisition software for capture of serial data and for transfer to any Windows ® application Load cell
Performance data
Load cell: 500, 2000, 5000 and 10,000g Force reading accuracy: ± 0.25% of full-scale reading Crosshead speed: 5-500 mm/min
Air pressure requirements: 75 psi/5.2 bar Angle measurement range/reading resolution: between 0° and 90° (selectable in 0.1°)/0.36° or better Position measurement accuracy: ± 0.1% of full-scale distance
Force units/Distance units: g, oz, lb, N, kg/in, cm, mm Power requirements: 110-120/220-240 V, 50/60 Hz, 33 W (operating) Fuse rating: 6 A @ 110 V, 60 Hz; 3 A @ 220 V, 50 Hz
Sample size opening force/bending force

  • from 25.4 to 457.2 mm when flat
  • up to 152.4 mm sample width
  • up to 6.35 mm sample thickness
Safety features

  • electronic overload protection system
  • angle over-travel limit switch
  • load cell incorporates mechanical limit stops
  • upward and downward motion limit switches
  • emergency stop button
For further information please contact our sales team on 01223 492081 or via