Dual chamber orifice fitting
A dual chamber orifice fitting including a first chamber maintained in fluid communication with a pipeline and a second chamber maintained in fluid communication with the first chamber. The fitting includes sealing member formed as an eccentric plug member that is selectively rotatable from a first position wherein the sealing member seals the first chamber from the second chamber, and a second position wherein the sealing member permits the first chamber to be placed in fluid communication with the second chamber. The sealing member includes a curved sealing surface having a pocket recessed therein for containing a non-metallic insert seat. The non-metallic insert seat sealingly engages a seat plate when the sealing member is in the first position. A retainer plate retains the insert seat in the recessed pocket.
1. A sealing member for a dual chamber orifice fitting, rotatable from a first position wherein the sealing member seals the two chambers from each other and a second position wherein the two chambers are in fluid communication with each other, the sealing member comprising:
an eccentric elongated body having two ends and a curved sealing surface, the sealing surface having a pocket recessed therein for containing an insert seat;
a non-metallic insert seat disposed in the pocket and configured to sealingly engage a seat plate when the sealing member is in the first position; and
a retainer plate disposed on a surface of the insert seat and configured to retain the insert seat in the recessed pocket.
2. The sealing member of claim 1 , wherein the insert seat comprises a material selected from the group consisting of plastics, thermoplastics, polytetrafluoroethylene, and ceramics.
3. The sealing member of claim 2 , wherein the insert seat comprises polytetrafluoroethylene.
4. The sealing member of claim 1 , wherein the insert seat comprises a raised lip around a circumference of the insert seat.
5. The sealing member of claim 1 , wherein the retainer plate includes grooves on a surface of the retainer plate that contacts the insert seat.
6. The sealing member of claim 1 , further comprising shafts connected to each of the ends of the body.
7. The sealing member of claim 6 , wherein the shafts are welded or pinned to the body.
8. The sealing member of claim 6 , wherein the body and the shafts are cast as a unit.
9. The sealing member of claim 1 , wherein the body is essentially C-shaped.
10. A sealing configuration for a dual chamber orifice fitting, comprising:
a sealing member rotatable from a first position wherein the sealing member seals the two chambers from each other and a second position wherein the two chambers are in fluid communication with each other, the sealing member comprising:
an eccentric elongated, essentially C-shaped body having a two ends and a curved sealing surface, the sealing surface having a pocket recessed therein for containing a non-metallic insert seat;
a non-metallic insert seat disposed in the pocket and configured to sealingly engage a seat plate, when the sealing member is in the first position;
a retainer plate disposed on a surface of the insert seat and configured to retain the insert seat in the recessed pocket; and
shafts connected to each of the ends of the body; and
a seat plate having an opening for providing fluid communication between the two chambers, the seat plate configured to sealingly engage the insert seat when the sealing member is in the first position.
11. The sealing configuration of claim 10 , wherein the insert seat comprises a raised lip around a circumference of the insert seat that sealingly engages the seat plate when the sealing member is in the first position.
12. An improved dual chamber orifice fitting, comprising,
a first chamber maintained in fluid communication with a pipeline, a fluid flowing in the pipeline passing through the first chamber;
a second chamber selectively maintained in fluid communication with the first chamber;
a sealing member formed as an eccentric plug member selectively rotatable from a first position wherein the sealing member seals the first chamber from the second chamber, and a second position wherein the sealing member permits the first chamber to be placed in fluid communication with the second chamber, the eccentric plug member traveling along an eccentric path between the first and second positions;
wherein the improvement comprises:
a sealing member comprising;
an elongated, essentially C-shaped body having a two ends and a curved sealing surface, the sealing surface having a pocket recessed therein for containing a non-metallic insert seat;
a non-metallic insert seat disposed in the pocket and configured to sealingly engage a seat plate when the sealing member is in the first position;
a retainer plate disposed on a surface of the insert seat and configured to retain the insert seat in the recessed pocket; and
shafts connected to each of the ends of the body.