VARIABLE LINE SIZE AVERAGING PITOT TUBE

摘要

Systems, apparatus and methods are disclosed for coupling an averaging picot tube (APT) primary element to a process pipe. A mounting assembly mounts the APT primary element to the process pipe such that a length of the APT primary element extending into the process pipe is adjustable to accommodate different sized process pipe diameters. The mounting assembly includes a weld coupling coupled to the process pipe over an opening in the process pipe and having the APT primary element extending therethrough into the process pipe. An extension pipe nipple is connected to the weld coupling and has the APT primary element extending therethrough such that a transition between a neck section and a sensor section of the APT primary element is positioned inside the extension pipe nipple. A union component, a ferrule, and a cap keep the APT primary element in the mounted position and form a process seal.

主权项

1. A process variable monitoring system for measuring a process variable indicative of a flow rate of a process fluid in a range of different sized process pipes, the system comprising:
a process variable transmitter; a pressure sensor in the process variable transmitter; an averaging pitot tube (APT) primary element having a distal region including one or more slots, the APT primary element being extendable into the process pipe to couple process pressures of the process fluid to the pressure sensor such that the pressure sensor provides as an output pressure measurement indicative of the flow rate of process fluid in the process pipe, wherein the distal region including the one or more slots is sized such that for larger diameter process pipes the one or more slots span a smaller percentage of the pipe diameter than for smaller diameter pipes; and a mounting assembly configured to mount the APT primary element to the process pipe and provide a process seal such that a length of the APT primary element extending into the process pipe is adjustable for different sized process pipes.