US 5,845,909 A · Stuffing box with improved packing rings and method

Abstract

A stuffing box 10, 60 designed for sealing engagement with a rod member R includes a plurality of stacked packing rings 32, 110, 150, 210, and a gland member 42, 64 axially moveable relative to the stuffing box body 12, 62 for varying the compressive force on the packing rings. Each packing ring comprises an annular rubber carrier 34, 112, 152, 212 having tapered upper and lower surfaces, and an annular plastic dynamic seal 36, 114, 154, 214 for sealing engagement with the rod member. Gland member 42, 64 exerts an axially compressive force on the radially exterior portion of each angularly wedged packing ring and thereby generates a radial inwardly directed biasing force on each plastic dynamic seal through the rubber carrier for sealing engagement of the dynamic seal with the rod member. Each packing ring includes an annular recess in at least one of the tapered upper and lower surfaces for thermal expansion of the rubber carrier, for flexing of the packing ring, and for increasing radial forces on the dynamic seal.

Claims19

Dependent claims

A stuffing box for sealing engagement with an elongate member movable with respect to and passing through the stuffing box to seal fluid within the stuffing box, the stuffing box comprising:

a stuffing box body having an interior surface defining a central stuffing box axis;
one or more axially spaced packing rings, each of the one or more packing rings comprising annular compressible carrier formed from a first selected material, and an annular plastic dynamic seal supported within an annular interion cavity and extending radially inward to a radially inward surface of the compressible carrier, the one or more compressible carriers each including an upper surface, a lower surface, and a radially outer surface for sealing engagement with the interior surface of the stuffing box body, and the one or more annular plastic dynamic seals each including a radially interior surface for sealing engagement with the elongate member;
and
a gland member movable relative to the stuffing box body for varying an axially compressive force on the one or more packing rings and thereby generating a radial inwardly directed biasing force on the one or more plastic dynamic seals through the respective compressible carrier for sealing engagement of the one or more plastic dynamic seal, with the elongate member.

1 more element

A packing ring for positioning within an interior of a stuffing box body for sealing engagement between the stuffing box body and an elongate member movable with respect to and passing through the stuffing box body, the packing ring comprising:

an annular compressible carrier including a tapered upper surface, a tapered lower surface, and a radially outer surface for sealing engagement with the stuffing box body;
an annular plastic dynamic seal supported within an annular interior cavity and extending radially inward to an inward surface of the compressible carrier and including a radially interior surface for sealing engagement with the elongate member;
the compressible carrier being configured to receive an axially compressive force and in response thereto generate a radially inward directed biasing force on the plastic dynamic seal through the compressible carrier for sealing engagement of the plastic dynamic seal with the elongate member;
and
an annular recess in at least one of the tapered upper surface and the tapered lower surface of the compressible carrier, the annular recess having a volume of at least five percent of the volume of the compressible carrier to accommodate thermal expansion of the compressible carrier.

2 more elements

A method of sealing between a stuffing box body having an interior surface defining a central stuffing box axis and an elongate member movable with respect to and passing through the stuffing box body, the method comprising:

positioning one or more packing rings within the stuffing box body, the one or more packing rings each comprising an annular compressible carrier and an annular plastic dynamic seal supported within an annular interior of the compressible carrier, the one or more compressible carriers each including an upper surface, a lower surface, and a radially outer surface for sealing engagement with the interior surface of the stuffing box body, and the one or more annular plastic dynamic seals each including a radially interior surface for sealing engagement with the elongate member;
and
selectively moving a gland member relative to the stuffing box body for varying an axially compressive force on the one or more packing rings and thereby wedging each of the one or more packing rings between the stuffing box body and the elongate member to generate a radially inward directed biasing force on the one or more plastic dynamic seals through the respective compressible carrier for sealing engagement of the one or more plastic dynamic seals with the elongate member.

Dependencies are inferred from the claim text.

Stuffing box with improved packing rings and method

Life of this patent

Stuffing box with improved packing rings and method

Life of this patent

Abstract

Claims19