초록 ▼

A control valve having a seat ring assembly constructed from a unitary piece of material is disclosed. The seat ring assembly may include a base which serves as a valve seat for the valve plug of the valve, and which includes a plurality of exterior threads adapted to rotatably attach to a plurality

A control valve having a seat ring assembly constructed from a unitary piece of material is disclosed. The seat ring assembly may include a base which serves as a valve seat for the valve plug of the valve, and which includes a plurality of exterior threads adapted to rotatably attach to a plurality of interior threads provided within the valve body. The seat ring assembly may also include a post-guided bearing surface to maintain alignment of the valve plug to the valve seat. The seat ring assembly can be secured to the valve body simply by threadably attaching the elements. Moreover, by providing the valve seat and the guide surface as integral parts of the seat ring assembly, manufacturing costs and maintenance requirements are reduced and subsequent seal leak performance is increased.

대표청구항 ▼

What is claimed is: 1. A control valve having a valve body and an inlet, an outlet, and a chamber between the inlet and the outlet, the control valve comprising; a shiftable valve plug mounted within the valve body for sliding movement and having a valve stem; a seat ring assembly comprising a subs

What is claimed is: 1. A control valve having a valve body and an inlet, an outlet, and a chamber between the inlet and the outlet, the control valve comprising; a shiftable valve plug mounted within the valve body for sliding movement and having a valve stem; a seat ring assembly comprising a substantially cylindrical unitary body, the seat ring assembly disposed within the chamber and having a base defining a valve seat sized to receive the valve plug, a threaded connection joining the base to the valve body such that the seat ring assembly is secured in place exclusively by the threaded connection, the seat ring assembly further including a guide portion spaced away from the base and a bore extending between the base and the guide portion; a bushing disposed adjacent the guide portion, the bushing sized to guide a portion of the valve plug, the bushing and the valve plug sized to maintain the valve plug substantially concentric with the valve seat. 2. The control valve of claim 1, wherein the control valve is unbalanced. 3. The control valve of claim 1, wherein the seat ring assembly is fastened to the valve body without any gasket therebetween. 4. The control valve of claim 1, wherein the seat ring assembly includes a wall extending between the base and the guide portion and having at least one aperture. 5. The control valve of claim 1, wherein the seat ring assembly includes a wall extending between the base and the guide portions and having a plurality apertures oriented in a predetermined pattern. 6. The control valve of claim 5, wherein at least some of the plurality of apertures include a predetermined shape. 7. The control valve of claim 5, wherein at least some of the plurality of apertures are drilled holes defining a smooth aperture. 8. The control valve of claim 1, wherein the valve plug includes an elongated cylindrical portion having a chamfered circumferential surface sized to engage the valve seat and a nose section, the cylindrical portion sized to engage both the guide portion and the valve seat at the same time when the chamfered circumferential surface is engaging the valve seat, the nose section shaped so as to provide desired flow characteristics. 9. The control valve of claim 1, wherein the guide portion includes a bushing, the bushing sized to engage the valve plug. 10. A seat ring assembly for a valve having a throttling element disposed within a valve body, the assembly comprising: a substantially cylindrical unitary housing having a first end, a second end, and a central bore extending along a longitudinal axis from the first end to the second end and sized to receive the throttling element; the housing including a wall having at least one aperture; the first end of the housing having a section of a reduced interior diameter sized to slidingly engage and guide an exterior surface of the throttling element; and the bore forming a valve seat disposed along the axis and adjacent the second end of the housing, the valve seat sized to sealingly engage the throttling element; the second end of the housing including threads sized to engage an interior threaded portion of the valve body, the housing secured within the valve body exclusively by a threaded connection formed between the threads and the threaded portion. 11. The seat ring assembly of claim 10, wherein the reduced diameter section of the first end is formed by positioning a bushing within the first end. 12. A method of assembling a control valve, comprising: inserting a unitary post-guided seat ring assembly into a control valve body, the seat ring assembly having a first end defining a reduced diameter section sized to engage and guide an exterior surface of a throttling element and a second end having a valve seat sized to sealingly engage the throttling element and a threaded exterior surface; securing the post-guided seat ring assembly within the control valve body exclusively by threadably attaching the second end of the integrated post-guided seat ring assembly to the control valve body; and securing a bonnet assembly to the control valve body. 13. The method of claim 12, including forming the seat ring assembly to provide an outer structure, the outer structure surrounding a hollow, the hollow extending from the first end to the second end. 14. The method of claim 12, including providing a bushing adjacent the second end, the bushing sized to engage the valve plug.