Abstract: Disclosed is an apparatus for swabbing wells. A cup type swab and dump valve are carried on the same mandrel. The dump valve protects the apparatus from excessive fluid load and drag.

Abstract: This patent application discloses a swab mandrel having thereon a swab with reinforcing wires imbedded at approximately the mid-point of the wall of the swab for a substantial distance to permit the swab to have fluid film lubrication with the tubing in which the wires at the upper end of the swab are approximately at the outer diameter of the swab and are sled shaped to bridge couplings in a tubing. The swab further has a restraining ring around the lower end thereof which supports the body of resilient material and restrains outward movement but is spaced from the wires to permit the wires to move radially outward a limited distance. To insure that a proper support is provided for the swab both above and below a special two piece support is provided for engagement with the bottom of the swab and with the top of the reinforcing wires.