Temperature Adjustment Factors

In general, the strength and therefore the pressure rating of metal hose decreases as the temperature increases. Thus, as the operating temperature of a metal hose assembly increases, its maximum allowable working pressure decreases.

The pressure ratings shown in Penflex catalog specifications charts for corrugated and interlocked hose are valid at 70°F. Elevated service temperatures will decrease these pressure ratings by factors shown in the following chart. Derating factors are based on braid alloy. Please keep in mind, maximum working temperature of the end fittings and their method of attachment also need to be considered when working with increased operating temperatures.

Penflex developed its derating factors after gathering raw data on tensile strength at elevated temperatures from major material suppliers and taking the lowest values in each category for the various alloys. For this reason, they may be more conservative than derating factors published by NAHAD or ISO 10380.

Temperature Adjustment Factors Based on Braid Alloy

Please note, calculator assumes 304/304L for P3, P4, 700, 800, 900, 1400 and P5 Series hoses; Monel 400 for 740 Series; Hastelloy® C-276 for 776 Series; Inconel® 625 for 625 Series; and Bronze for 794 Series.

While MAWP will populate for stainless steel hoses over 1000°F, ASTM 240 doesn’t recommend using the 300 series alloys above this temperature. Inconel 625 may be a more suitable option; contact us to discuss further.