| 摘要 |
<p>HIGH TEMPERATURE PRESSURE SENSING INSTRUMENT AND METHOD This invention relates to apparatus and methods for filling a conventional Bourdon tube with an outgassed fluid to permit use of the Bourdon tube to measure fluid pressures at high temperatures. The filling device includes a hot reservoir containing hydraulic fluid that has been heated to facilitate outgassing and a cold reservoir in fluid communication with the hot reservoir to prevent exposure of the fluid in the hot reservoir to oxygen. A vacuum line connected to the cold reservoir permits evacuation of the filling apparatus, the Bourdon tube and a typical bellows that may be attached to the Bourdon tube. The bellows is mechanically compressed and provided with a center post to reduce the volume of the bellows by about fifty percent. After the Bourdon tube, the bellows and the hydraulic fluid in the hot reservoir have been heated and outgassed, the vacuum is removed from the cold reservoir to permit hydraulic fluid to flow from the hot reservoir into the bellows and Bourdon tube. After the Bourdon tube and bellows are filled, the filling apparatus is disconnected from the fill port, which is then plugged to prevent leakage.</p> |
