公开(公告)号：US20220121124A1

公开(公告)日：2022-04-21

申请号：US17298202

申请日：2019-11-19

Applicant: ASML NETHERLANDS B.V.

Inventor： Bas Bastiaan Cornelis Gijsbertus VAN ELTEN ,  Philippe Jacqueline Johannes Hubertus Anthonius HABETS ,  Remco VAN DE MEERENDONK

IPC: G03F7/20 ,  F15D1/02 ,  F16L55/027

Abstract: A flow restriction, a flow restriction assembly and methods for manufacturing the flow restriction and the flow restriction assembly. The flow restriction is for use in a pipe so as to restrict the flow of a fluid and includes a body extending along an axis and that has i) a central portion having an essentially constant cross section, ii) an upstream portion, wherein the cross-sectional area of the upstream portion monotonically increases in a downstream direction along the axis; and iii) a downstream portion, wherein the cross-sectional area of the downstream portion monotonically decreases in the downstream direction. The flow restriction also has a plurality of central portion projections for engaging the inner surface of the pipe, each of which projects from the surface of the central portion in a direction perpendicular to the surface of the central portion by a distance of less than 500 μm.