Pipe section for flowmeter pressure sensor - constricted section cast from one mould suited for finishing for different ranges

摘要

The effective pressure sensor for flow measurement uses an annular chamber formed by a constriction in a pipe having a thickened waist containing a separate cylindrical section for the sensing of the minus pressure. The annular chamber (6) has four or more breakthroughs (9) round the circumference of the waist for the introduction of pattern core supports and for removal of the moulding sand, and for the introduction of take-off stubs for optional fittings of single bore take-off points. The waist (5) with the wall section (7) and the apertures (9) are cast in one piece with the pipe section (1), the wall thicknesses of the pipe (1) and the cylindrical wall section (7) inside the waist are such that, together with the axial length of the annular section, the same pattern may be used for casting different sensor units with different internal diameters (4) at the constriction.