Patent ID: 7426938

Claim:
A choke valve having a fluid flow path extending therethrough which is to be restricted or closed, comprising: a hollow valve body assembly having an inlet bore and an outlet bore substantially at right angles, and a main bore which is an extension of the outlet bore and which communicates with the inlet bore; a tubular sleeve having a side wall positioned in the main bore across the inlet bore and forming only one pair of diametrically opposed side ports communicating with the inlet bore, the side ports being located to overlap the intersection of the centre axes of the inlet and outlet bores, and such that an axis through a midpoint of the side ports is offset relative to the centre axis of the inlet bore so that direct impingement of fluid along the centre axis of the inlet bore is on the side wall of the tubular sleeve; a flow trim within the tubular sleeve comprising a stationary tubular cage aligned with the body outlet, and a flow collar or plug slidable along the side wall of the cage, the cage side wall forming an internal bore aligned with the outlet bore and at least one pair of diametrically opposed main flow ports located to overlap the intersection of the centre axes of the inlet and outlet bores, one pair of the at least one pair of main flow ports being aligned with the side ports of the tubular sleeve to communicate directly with the side ports, whereby fluid may enter the choke valve through the inlet bore and pass through the main flow ports at reduced pressure and continue through the outlet bore; a bonnet connected with and closing the upper end of the tubular sleeve and the body, the bonnet being disengagably connected with the body; and a stem for biasing the flow collar or plug over the main flow ports.