Abstract: The device includes a main flow control valve and associated packings designed for effective operation under extreme conditions associated with the pumping of high viscosity asphaltic crude wherein the formation includes toxic gases, and where the formation is produced using steam flooding techniques. The main valve seat and the associated valve closure, consisting of a reciprocating ram and packing plug, are coaxial with the pump polished rod. The valve seat includes tapered walls defining a shoulder which partially confronts the ram plug; and the ram plug is formed of a compressible material formed to the shape of the valve seat. The packing plug is retained on the end of the ram by axial tie rods and a retaining ring, which ring may engage the valve seat shoulder to effect axial compression of the packing plug between the retaining ring and ram face, and consequent radial expansion into sealing engagement.

Abstract: A gland body is coupled at its proximal end to a supporting housing by means of a union. A first packing chamber, for a static shutdown packing, is formed at the proximal end of the gland body, with a wedge ring forming the base of the chamber. The wedge ring has a beveled surface diverging outwardly from the base; and a packing body has a complementary beveled surface confronting the wedge ring. A mandrel having a reduced diameter proximal end is received within the gland body for urging the first packing toward the wedge ring. A second packing chamber is formed at the distal end of the gland body confronting the mandrel; and a packing cap threaded onto the distal end of the body compresses the second packing body to seal the mandrel and gland body. The distal end of the mandrel is enlarged to form a third packing chamber confronting the shaft for receiving a third packing body being a dynamic packing for the reciprocating shaft.