The graph on the right side will help you to determine the recommended working pressure (approx. 0.25 x short time burst pressure) for PTFE 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.
For PTFE 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).