초록

A bellows energized seal assembly includes a seal body, a main seal that is axially slidable within the seal body, and a bellows connected to the seal body and the main seal. The bellows both biases the main seal and provides a seal between the seal body and the main seal.

대표청구항 ▼

1. A bellows energized seal assembly for a rotary control valve, the bellows energized seal assembly comprising: a seal body, the seal body including a body annular flange that extends inwardly, substantially perpendicular to a longitudinal axis of the bellows energized seal assembly;a main seal axi

1. A bellows energized seal assembly for a rotary control valve, the bellows energized seal assembly comprising: a seal body, the seal body including a body annular flange that extends inwardly, substantially perpendicular to a longitudinal axis of the bellows energized seal assembly;a main seal axially slidable relative to the seal body; anda bellows connected to the seal body and to the main seal, the bellows both biasing the main seal towards a ball element, and providing a seal between the seal body and the main seal,wherein the seal body includes an outer body portion that extends substantially parallel to the longitudinal axis of the bellows energized seal assembly, the main seal includes an outer seal portion that extends substantially parallel to the longitudinal axis of the bellows energized seal assembly, the outer seal portion is disposed between the bellows and the outer body portion, and the body annular flange forms a stop for the outer seal portion, thereby limiting longitudinal displacement of the main seal relative to the seal body, the outer seal portion contacting the body annular flange between the bellows and the outer body portion when the main seal is located at the stop limit. 2. A bellows energized seal assembly according to claim 1, wherein the body annular flange forms a seat for the bellows. 3. A bellows energized seal assembly according to claim 1, wherein the main seal includes a seal surface that is coated with one of stainless steel, PEEK, graphite, solid carbon, PTFE, and a PTFE composite. 4. A bellows energized seal assembly according to claim 1, wherein the bellows is made from one of stainless steel, Inconel/Hastelloy, and titanium. 5. A bellows energized seal assembly according to claim 1, wherein the bellows is welded to one of the seal body and the main seal. 6. A bellows energized seal assembly according to claim 1, wherein the bellows is disposed radially inward of both the outer body portion and the outer seal portion. 7. A bellows energized seal assembly according to claim 1, wherein the main seal includes a seal annular flange. 8. A bellows energized seal assembly according to claim 7, wherein the seal annular flange extends inwardly, substantially perpendicular to the longitudinal axis of the bellows energized seal assembly. 9. A bellows energized seal assembly according to claim 8, wherein the seal annular flange forms a seat for the bellows. 10. A bellows energized seal assembly according to claim 9, wherein the bellows is disposed between the body annular flange and the seal annular flange. 11. A rotary control valve comprising: a valve body having a fluid inlet and a fluid outlet;a ball element disposed within the valve body; anda bellows energized seal assembly disposed within the valve body, the bellows energized seal assembly including: a seal body, the seal body including an annular flange that extends inwardly, substantially perpendicular to a longitudinal axis of the bellows energized seal assembly;a main seal axially slidable relative to the seal body; anda bellows connected to the seal body and to the main seal, the bellows both biasing the main seal towards the ball element and providing a seal between the seal body and the main seal,wherein the seal body includes an outer body portion that extends substantially parallel to the longitudinal axis of the bellows energized seal assembly, the main seal includes an outer seal portion that extends substantially parallel to the longitudinal axis of the bellows energized seal assembly, the outer seal portion is disposed between the bellows and the outer body portion, and the body annular flange forms a stop for the outer seal portion, thereby limiting longitudinal displacement of the main seal relative to the seal body, the outer seal portion contacting the body annular flange between the bellows and the outer body portion when the main seal is located at the stop limit, andwherein the ball element cooperates with the main seal of the bellows energized seal assembly to control fluid flow through the rotary control valve. 12. A rotary control valve according to claim 11, further comprising a static seal between the valve body and the bellows energized seal assembly. 13. A rotary control valve according to claim 11, further comprising one of a threaded connection, an interference fit, and a weld between the valve body and the bellows energized seal assembly. 14. A rotary control valve according to claim 11, wherein the seal body includes an outer annular flange extending radially outward from the seal body. 15. A rotary control valve according to claim 14, wherein the outer annular flange rests against the valve body. 16. A rotary control valve according to claim 15, further comprising an o-ring seal between the outer annular flange and the valve body. 17. A rotary control valve according to claim 16, wherein the o-ring is disposed in an annular recess in the valve body.