| 摘要 |
A flow controlling device for location in a pipeline comprises an elongated body (10) having a flange (11) at one end and a tapering recess (12) which extends from the flanged end of the body (11, 14) and tapers inwardly (12) towards the other end of the body to define a flow aperture (19) the size of which can be selected by cutting the body transversely. |
