CUT-IN ELECTROACOUSTIC TRANSDUCERS MOUNTING

     In order to simplify installation of liquid flow measurement units based on the ultrasonic flowmeters, a special technology (technique, set of instruments and tools) was designed by specialists of “Energouchet” jsc. for mounting cut-in electroacoustic transducers (EAT) into the pipeline walls.

     The PUVDD technical device is used for precise marking of input/output acoustic channel points on the pipeline surface and drilling operations. It allows to perform operations round pipelines as well as substantially elliptic pipelines.

     Mounting operation is performed with liquid discharge (pipeline empting) or without it, i.e. without a break in the liquid transportation process.

     PIPELINE SPECIFICATIONS

- material: steel;

- nominal diameter: from 100 to 4000 mm;

- type of liquid transported through the pipeline: non-aggressive liquids (water, heat carrier, oil etc.).

     For mounting on empty pipelines the following operations are performed:

- attachment of PUVDD mounting tool to the pipeline;

- marking hole centers for EAT installation;

- drilling holes in the pipeline walls at a certain angle to the pipe longitudinal axis;

- welding branch-pipe holders for EAT;

- measurement of geometrical dimensions of the acoustical channels;

- installation of EAT;

     For mounting on filled pipelines the following operations are performed:

- marking hole centers for EAT installation;

- welding branch-pipe holders for EAT;

- attachment of PUVDD mounting tool to the pipeline;

- milling the holes in the pipeline walls at a certain angles to the pipe longitudinal axis;

- mill extraction and installation of fitting plugs;

- measurement of geometrical dimensions of the acoustical channels;

- EAT installation;

- extraction of EAT and installation of fitting plugs (if required).

     The pipeline remains hermetically sealed during milling and EAT installation/extraction operations.

     The advantage of our technique is the ability to install acoustic channels at an acute angle to the pipeline longitudinal axis which enables to perform more precise measurement of small flow of liquids.

     Besides, several (up to 5) acoustic channels can be installed at a pipeline which allows to reduce measurement errors. The technique can be applied for liquid flow measurement in large diameter pipelines by means of multi-channel ultrasonic flowmeters with 0,25 - 0,5 % relative error.