| 摘要 |
<p>The conventional expansion packer includes upper and lower elements joined to a central element with the junctions being perpendicular to the longitudinal axis and with the upper and lower elements being formed of a resilient material such as rubber, having a higher durometer reading than the center section which is also made of a resilient material such as rubber. When compressed lengthwise to pack off a well drilling, severe strain occurs at the junctions of the center section and the end sections often causing tearing or fracturing. The present device is provided with junctions between the outer and center sections which taper or incline outwardly and towards the transverse axis of the center section. Furthermore, cylindrical flexible webs span the junctions axially and formed from a flexible material such as canvas or the like to preserve the integrity of the bonding between the sections.</p> |
