| 摘要 |
<p>The circuit has gas distribution points each having a differential control (140) cooperating with the pilot valve (120) and the security valve (130) upstream of the regulator and expander (110) to ensure automatic closure of the security valve controlled by the pilot valve when the upstream pressure (pa) in the main duct exceeds a set value. The differential control automatically causes, after re-establishment of an upstream pressure below the set pressure when the realigning of the security valve if the regulator-expander of the expansion point concerned is not introduced without leakage at the level of the valve, maintained closure of the security valve if the regulator-expander has an absence of sealing at the valve gate level.</p> |
