Reverse flow flow trim for choke valve

1. A choke valve for use in reverse flow when mounted on a wellhead or manifold, the choke valve comprising:

a valve body forming a T-shaped bore comprising a vertically extending bottom opening and a horizontally extending side opening;

a bonnet connected with and closing the upper ends the body, the bonnet being disengagably connected with the body;

a flow trim positioned in the T-shaped bore, the flow trim comprising a tubular cage having a side wall forming an internal bore aligned with the body bottom opening, and a plurality of flow ports formed in the side wall at the body side opening, each of the plurality of flow ports being positioned only at the body side opening for alignment with the body side opening, whereby in reverse flow mode in the valve body, fluid from the bottom opening enters the cage and exits only through the plurality of flow ports directly into the body side opening, the flow trim further comprising an external flow collar or internal plug for sliding along the cage side wall to throttle the plurality of flow ports; and

a stem extending through the bonnet, for biasing the flow collar or plug.

2. The choke valve of claim 1 , wherein:

a) the valve body forms a vertical cartridge chamber at the intersection of the body side and bottom openings;

b) the flow trim, stem and bonnet form part of, and are housed within, a removable insert assembly to position flow trim in the cartridge chamber, the removable insert assembly comprising:

i. a tubular cartridge having a side wall forming an internal bore and a single side port communicating with the body side opening, whereby fluid may enter through the body bottom opening and exit through the cartridge side port to the body side opening, the cartridge having upper and lower ends, the lower end being seated and sealed in the valve body adjacent the bottom opening;

ii. the bonnet connected with and closing the upper ends of the cartridge and the body, the bonnet being disengagably connected with the body;

iii. the flow trim positioned in the cartridge internal bore, the flow trim comprising the tubular cage having the side wall forming the internal bore aligned with the body bottom opening, and each port of the plurality of flow ports being positioned only at the cartridge side port and the body side opening for alignment with both the cartridge side port and the body side opening, whereby fluid from the bottom opening may enter the cage and pass out only through the plurality of flow ports directly into the body side opening, the flow trim further comprising the external flow collar or internal plug for sliding along the cage side wall to throttle the plurality of flow ports; and

iv. the stem extending through the bonnet, for biasing the flow collar or plug.

3. The choke valve of claim 2 , wherein the flow trim includes the external flow collar for sliding along the cage side wall, and wherein the cage is formed with the plurality of flow ports arranged in a cluster, each flow port being aligned with the body side opening, said plurality of flow ports being arranged in a pattern sized smaller to larger in a direction of opening so as to limit jetting through said ports as they are partially opened.

4. The choke valve of claim 2 , further comprising alignment means located between the cartridge and the cage for aligning the cartridge side port and the plurality of flow ports with the body side opening.

5. The choke valve of claim 4 , wherein the flow trim includes the external flow collar for sliding along the cage side wall, and wherein the cage is formed with the plurality of flow ports arranged in a generally circular cluster and sized smaller to larger in the direction of opening, each flow port being aligned with the body side opening.

6. The choke valve of claim 5 , further comprising a seat assembly formed across an annulus existing between the cartridge and the cage, and wherein the alignment means comprises alignment pins between the seat assembly, the cartridge and the cage.

7. The choke valve of claim 1 , wherein the flow trim includes the external flow collar for sliding along the cage side wall, and wherein the cage is formed with the plurality of flow ports arranged in a cluster, each flow port being aligned with the body side opening, said plurality of flow ports being arranged in a pattern sized smaller to larger in a direction of opening so as to limit jetting through said ports as they are partially opened.

8. The choke valve of claim 1 , further comprising:

a tubular sleeve having a side wall positioned vertically in the T-shaped bore and having the single side port formed in the tubular sleeve side wall to communicate with the body side opening, whereby fluid may enter through the body bottom opening and exit through the tubular sleeve side port to the body side opening;

the flow trim being positioned in the tubular sleeve, with each of the plurality of flow ports of the cage being positioned only at the tubular sleeve side port and the body side opening for alignment with both the tubular sleeve side port and the body side opening; and

alignment means located between the tubular sleeve and the cage for aligning the tubular sleeve side port and the plurality of flow ports with the body side opening.

9. A removable insert assembly suitable for use within a choke valve having a valve body forming a T-shaped bore comprising a vertically extending body bottom opening and a horizontally extending body side opening, and forming a vertical cartridge chamber at the intersection of the body and side openings, wherein the removable insert assembly comprises:

i. a tubular cartridge having a side wall forming an internal bore and a single side port communicating with the body side opening, whereby fluid may enter through the body bottom opening and exit through the cartridge side port to the body side opening, the cartridge having upper and lower ends, the lower end being seated and sealed in the valve body adjacent the bottom opening;

ii. a bonnet connected with and closing the upper ends of the cartridge and the body, the bonnet being disengagably connected with the body;

iii. a flow trim positioned in the cartridge internal bore, the flow trim comprising a tubular cage having a side wall forming a cage internal bore aligned with the body bottom opening, and a plurality of flow ports formed in the side wall, wherein each port of the plurality of flow ports is positioned only at the cartridge side port and the body side opening for alignment with both the cartridge side port and the body side opening, whereby in reverse flow mode in the valve body, fluid from the bottom opening may enter the cage and pass out only through the plurality of flow ports directly into the body side opening, the flow trim further comprising an external flow collar or internal plug for sliding along the cage side wall to throttle the plurality of flow ports; and

iv. a stem extending through the bonnet, for biasing the flow collar or plug.

10. The removable insert assembly of claim 9 , wherein the flow trim includes the external flow collar for sliding along the cage side wall, and wherein the cage is formed with the plurality of flow ports arranged in a cluster, each flow port being aligned with the body side opening, said plurality of flow ports being arranged in a pattern sized smaller to larger in a direction of opening so as to limit jetting through said ports as they are partially opened.

11. The removable insert assembly of claim 9 , further comprising alignment means located between the cartridge and the cage for aligning the cartridge side port and the plurality of flow ports with the body side opening.

12. The removable insert assembly of claim 11 , wherein the flow trim includes the external flow collar for sliding along the cage side wall, and wherein the cage is formed with the plurality of flow ports arranged in a generally circular cluster and sized smaller to larger in the direction of opening, each flow port being aligned with the body side opening.

13. The removable insert assembly of claim 12 , further comprising a seat assembly formed across an annulus existing between the cartridge and the cage, and wherein the alignment means comprises alignment pins between the seat assembly, the cartridge and the cage.