When a fluid travels through an elbow or curved conduit in a piping system, it becomes turbulent. The flow stream next to the outer radius must travel a longer distance than the flow stream near the center. When this happens, the pressure distribution becomes uneven and the fluid separates into numerous secondary flows that swirl, rotate and have accelerated/reverse flows. Thus, the velocity pattern at the exit of the elbow becomes turbulent. This is the reason why a curved conduit can produce a greater pressure loss than a straight section of pipe. This flow turbulence will continue downstream from the elbow and will be detrimental to the operation of rotating equipment connected within 10 pipe diameters of the bend. The Cheng Rotation Vane (CRV®) was invented to eliminate the flow turbulence caused by an elbow or bend in a piping system.

The Cheng Rotation Vane (CRV®) consists of a set of stationary vanes in a cylindrical body and is placed immediately upstream of an elbow in a piping system. CRV® vanes are specifically designed so that they impart a gyroscopic motion to the following fluid. This gyroscopic motion counteracts the rotating motion of the fluid that is produced by the elbow. The CRV® enables the fluid to negotiate the turn through the elbow and exit the elbow with a flat velocity uniform velocity profile. Other flow benefits achieved when using a CRV® are a reduced pressure drop through an elbow, no fluid turbulence, less noise, less vibration and no fluid separation. The CRV® improves the flow of fluid through any type of elbow and thus turns the elbow into the equivalent of a straight length of pipe.

Flow conditioner is to be located directly at elbow inlet, within the vicinity of the upstream piping turn entrance and will rotate the fluid through the turn such that it exits the turn with a flat velocity profile. The flow conditioner shall have a zero angle of attack at the entrance and an aerodynamic shape such that it produces minimal pressure drop, if any depending on the application, fluid properties and velocity. The flow conditioner internals are to be stationary and welded/flanged to the pipe-stub housing. Available in 2" through 72" and larger at request.





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Our flow conditioners are custom made to specifically address each piping issue offering the greatest achievable flow correction.