| 摘要 |
<p>1463601 Well safety plugs ENTREPRISE DE RECHERCHES ET D'ACTIVITES PETROLIERES (ELF) 7 Nov 1974 [14 Nov 1973] 48234/74 Heading E1F A safety plug for sealing-off tubing 3 in a deep producing well comprises a hollow body 1 fitted within the tubing by means of O- ring seals 26, a valve member 19 having seating surfaces 19e, 19f at its upper and lower ends, which seating surfaces are capable of sealingly engaging upper and lower seats 12, 14 of the body, an axial push rod 18 connected to the valve member by means of a shearable member 21, a shearable member 20 for positioning the push rod and valve member relative to the body, and a spring 24a for biassing the valve member upwardly. The plug seals-off the tubing when pin 20 is sheared, this shearing being effected by extreme fluid pressure down the well, or by the application to the push rod of a tractive force, or by the dropping of a weight. A large tractive force applied to the push rod 18 shears pin 21 to permit the push rod to be removed.</p> |
