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TTS is the creation of Clarence Klassen of KlassENgineering Inc, klassen.on.ca
and has been put into App format by Steven Abbott
Typical Modulus Values
Modulus represents the strength of the web under tension.
Choose a Web, select the value and copy it.
Close this form and paste value into Modulus.
WebGPaMpsi
Acetate1.80.26
PC2.40.35
PE10.15
PET4.40.64
PMMA2.10.30
PP3.10.45
PVC2.80.41
Nylon 6 (PA)0.950.14
PI9.11.32
Board30.44
Bond1.80.26
Magazine10.15
LightWeightCoatedPaper5.50.80
MachineFinishedCoated5.70.83
NewsPrint40.58
FineCoatedPaper6.30.91
SuperCalendared7.91.15
Aluminium6910
Steel20029
Instructions and Terminology
The TSpan application uses the model of tension in a span between two traction points. Idler roller drag and inertia are not considered as they complicate the model enormously and most often idlers have only small effects.
The model comes from research at Oklahoma State University1.
This model shows the incremental tension response to a step change in speed at the 2nd roller in a web span.

A stready differential change in speed at the 2nd roller is often called draw. The important outputs are:
  1. The time constant Tc of the tension model. This is the time to reach 63% of the steady-state tension value.
  2. The steady-state tension value (N or lbf.) which will be achieved with an incremental speed difference between two rollers. This is commonly described as draw or ratio can be calculated from it.
  3. The steady-state gain of tension over incremental speed.
This tension model will be used in other Abbott Apps including ones for tension regulation through a drive speed or torque regulator.

Summary of Inputs and Outputs
The aim is to calculate the extra tension in the web caused by an increase in web speed of ΔV. This depends on the following inputs, along with derived output values

Inputs
SpanDistance between rollers (m or in)
GaugeThickness of web (mm or mil)
WidthWeb width (mm or in)
SpeedWeb speed(m/min or ft/min)
ΔVChange in web speed at the 2nd roller (m/min or ft/min)
ModulusElastic Modulus of the web(GPa or MPSI)
Outputs
AreaCross-sectional area of the web (m² or in²)
TcTime Constant of the tension response to a change in speed at the 2nd roller (s)
GainSteady-state Gain of the tension response (N/m/min or lbf/ft/min)
Final tension value (N or lbf) can be read from the graph. 1Tension Control Kee-Hyun Shin, TAPPI PRESS, 2000, ISNB 0-89852-348-6.