Bleed all pressure from the regulator by opening the test gun. Remove the test gun from the regulator. Remove the regulator from the manifold. Pressure readings taken downstream from the regulator result in lower readings due to friction losses which cannot be attributed to regulator performance. The pressure measured immediately at the regulator entry.
Frictional loss is minimal entering the regulator's high pressure area.
Therefore, an accurate high pressure gauge indicates the inlet pressure. A change in outlet pressure from a no-flow to a flowing condition while the inlet pressure remains constant. RISE An increase of outlet pressure as the inlet pressure decreases. A gradual increase in outlet pressure. Welding apparatus that is improperly maintained or repaired can be dangerous.