A new choke valve trim has been introduced to cope with the significant pressure drop inherent in wellhead start-up, whilst also providing minimum flow restriction during production. Designated MP, the trim can be specified with control valves or retrofitted to existing valve bodies from other choke valve manufacturer. In all cases the MP trim secures the valve seat without the use of a clamping cage, increasing the seat bore to maximise capacity and throughput.
Developed during years of providing choke valve application solutions throughout the world, the MP trim consists of two well-defined sections. The start-up section, comprising approximately the first 30% or so of travel, determined by the well pressure/flow profile, directs the flow through ports designed to impart significant friction on the fluid, resulting lower velocities and reduced pressure recovery characteristics. Valve noise, erosion and vibration are all reduced, increasing the operating life of the choke.
During production, when the pressure drop has reduced, the MP trim ensures high capacity by maximising the flow area in the inlet body cavity, through the trim and in the valve outlet section.
The MP is designed to overcome specific operating characteristics in wellhead and associated applications. The LP trim provides maximum capacity whilst the HP is designed for the demands of especially severe service.