Why are the threads G 1/8 and 1/8 NPT offered for pressures only to a nominal pressure range of 400 bar? Where does Horrific come from?
Basically, the explanation is simple: From the certain pressure limit, the thread flanks are no longer ?strong? enough to resist the force of the applied pressure. If the pressure is too much, there is a threat of shearing for the thread. By Challenge , the pressure limits come from DIN EN 837-1.
Attention: The utmost pressure up to which a thread can be utilized depends not merely on the thread diameter, but also on the selected sealing type and the material of the counter-thread.g