US 5,351,752 A · Artificial lifting system

Abstract

An artificial lifting system is designed for use at a pumping installation which has a pump drive at the surface or head end of a well and a reciprocating pump positioned in the lower end of the well. The artificial lifting system has a tubing string connected between the pump drive and the pump for performing the dual functions of reciprocating the pump plunger in response to activation of the pump drive, and for transporting oil from the underground source to the wellhead. The tubing string advantageously is constructed of a plurality of lightweight, non-metallic tubing segments which are axially connected to form an elongated conduit of several thousand feet in length. In the exemplary embodiment, the tubing segments are made of a glass and carbon reinforced epoxy resin. Preferably, the composite material has a density of approximately 0.1 pounds per cubic inch and a fiber content of approximately 60% by volume, with the resulting composite material having an elastic modulus in excess of 700,000 psi. The invention additionally is directed to various structural features for facilitating the implementation of such a composite lifting system.

Claims16

Dependent claims

An artificial lifting system for extracting oil and the like from an underground source, the lifting system being designed for use at a pumping installation having pump drive means at the head of a well and a pump with a reciprocable member secured in the lower end of the well, the improvement comprising

hollow tubing string means extending axially between the head of the well and the pump for performing the dual functions of reciprocating the reciprocable member in response to activation of the pump drive means and for transporting oil from the underground source to the wellhead,
the tubing string means including a plurality of tubing segments made of fiber-reinforced composite material and a fitting interconnected between adjacent ends of a pair of adjacent tubing segments for serially connecting said segments to define an elongated non-corrosive conduit, said fitting having a tapered sidewall received in the end of a tube segment and fibers wound about the fitting in an annular space between the tapered sidewall and the end of the tube segment to restrict withdrawal of the fitting from the tube segment end.

An artificial lifting system for extracting oil and the like from an underground source the lifting system being designed for use at a pumping installation having pump drive means at the head of a well and a pump with a reciprocable plunger secured in the lower end of the well, the improvement comprising

a tubing string connected between the pump drive means and the plunger and mounted for reciprocating movement through a wellhead assembly for performing the dual functions of reciprocating the plunger in response to activation of the pump drive means and for transporting oil from the underground to the wellhead;
a plurality of openings in an upper end of the tubing string for discharging oil which is transported thereby;
an elongated collection tube surrounding said tubing string openings;
anchor means for securing an upper end of the collection tube to the wellhead assembly;
and
seal means at a lower end of the collection tube for slidable sealing engagement with the tubing string, whereby the fixed collection tube defines an annular collection chamber around said tubing string openings and in communication with the wellhead assembly, said seal means comprising
an upwardly opening cylindrical housing connected to a lower end of the collection tube and having an end wall and an opening adapted for slidable engagement with the tubing string,
an annular cup seal having a downward and radially inwardly tapered sidewall in the housing, the cup seal having a central opening for slidably receiving the tubing string,
a radial projection on the tubing string for limiting upward movement of the cup seal relative to the tubing string, and
a spring between the bottom of the housing and the cup seal for biasing the seal into engagement with the radial projection to force the tapered sidewall into sealing engagement with the tubing string.

7 more elements

Dependencies are inferred from the claim text.

Artificial lifting system

Life of this patent

Artificial lifting system

Life of this patent

Abstract

Claims16