Pressure resistance, bending radius, tolerances and permeabilityGlossarypermeability The permeability of a solid describes its porosity towards other atoms, molecules or ions. It depends on the combination and the compactness of both substances. 

The graph below will help you to determine the recommended working pressure (approx. 0.25 x short time burst pressure) for PTFEGlossaryPTFE Polytetrafluoroethylene tubing. For working temperatures above +20 °C the working pressures stated in this graph have to be multiplied by the corresponding reduction factor. For temperatures below +20 °C no reduction factors have to be considered.
Example:
For PTFEGlossaryPTFE Polytetrafluoroethylene tubing with inner diameter of 6 mm and a wall thickness of
1 mm the working pressure at +20 °C is about 8.8 bar. At a temperature
of +50 °C, this value has to be reduced to 7.6 bar (pressure 8.8 bar x
reduction factor 0.87 = 7.65 bar).

The graph below will help you to determine the recommended working pressure (approx. 0.25 x short time burst pressure) for FEPGlossaryFEPTetraflouroethylene-Perflouropropylene tubing. For working temperatures from -50 °C to +150 °C the working pressures stated in this graph have to be multiplied by the corresponding reduction factor.
Example:
For FEPGlossaryFEPTetraflouroethylene-Perflouropropylene tubing with inner diameter of 6 mm and a wall thickness of 1 mm the working pressure at +20 °C is about 7.8 bar. At a temperature of +50 °C, this value has to be reduced to 6.1 bar (pressure 7.8 bar x reduction factor 0.78 = 6.1 bar).

The graph below will help you to determine the recommended working pressure (approx. 0.25 x short time burst pressure) for PFAGlossaryPFA Perfluoroalkoxy tubing. For working temperatures above +20 °C the working pressures stated in this graph have to be multiplied by the corresponding reduction factor. For temperatures below +20 °C no reduction factors have to be considered.
Example:
For PFAGlossaryPFA Perfluoroalkoxy tubing with inner diameter of 4 mm and a wall thickness of 1 mm the working pressure at +20 °C is about 14 bar. At a temperature of +50 °C, this value has to be reduced to 12 bar (pressure 14 bar x reduction factor 0.86 = 12 bar).

During the assembly of devices with fluoroplastic tubing we are often confronted with the problem of how to create the smallest bending radius when the space is limited. To avoid buckling of the tubing with all its negative aspects, the following graph will be helpful to determine the smallest possible bending radius.

Take the outer diameter indicated on the horizontal axis, then follow the line upwards until it crosses with the appropriate wall thickness. From this intersection, follow the line to the left until it reaches the vertical axis which shows the minimum bending radius.

Because of its special processing and the resulting structural conditions, PTFEGlossaryPTFE Polytetrafluoroethylene has a higher permeabilityGlossarypermeability The permeability of a solid describes its porosity towards other atoms, molecules or ions. It depends on the combination and the compactness of both substances.  than other thermoplastics. PFAGlossaryPFA Perfluoroalkoxy has at the same wall thickness a lower permeabilityGlossarypermeability The permeability of a solid describes its porosity towards other atoms, molecules or ions. It depends on the combination and the compactness of both substances.  than PTFEGlossaryPTFE Polytetrafluoroethylene due to its tight molecular structure.

For applications with low permeabilityGlossarypermeability The permeability of a solid describes its porosity towards other atoms, molecules or ions. It depends on the combination and the compactness of both substances.  or diffusion rates, PFAGlossaryPFA Perfluoroalkoxy and FEPGlossaryFEPTetraflouroethylene-Perflouropropylene tubing should be used.