| 摘要 |
An economical easily installable and easily removable seal assembly for use on water well casings comprises a dome having a central shaft threaded through a lower flange means so that rotation of the shaft compresses a rubber ring between the flange means and a lower rim of the dome, radially expanding the ring to grip the inside of a well casing with uniform pressure around the periphery of the ring, and also compresses an upper ring between the dome and the shaft.
|
