GB1028523A - Improvements in or relating to the measurement of density - Google Patents

Abstract

1,028,523. Moulding grinding wheels. SAUNDERS ROE & NUCLEAR ENTERPRISES Ltd. Nov. 26, 1964 [Jan. 10, 1964], No. 1126/64. Heading B5A. [Also in Division G1] The density of articles being produced in a moulding press is measured without removing them from the press. The press, which may produce grinding wheels from silicon carbide alumina, comprises a well 2, with a central post 7 which is filled by the material 1 to be compressed. Surplus material is removed by a scraper, Fig. 2 (not shown), and the remainder compressed by the press head 5. The press is provided with collimating tubes 11 passing beta or gamma radiation from a shielded source 8 to a scintillation crystal 14 coupled to a photomultiplier 15 through the compressed material. The density of the material affects the intensity of radiation reaching the scintillator and is measured by counting the output pulses of the photo-multiplier during a one second interval immediately following the compression. The count is printed out and may be used to vary moulding parameters such as the well depth, the moulding pressure or the composition of the materials compressed. The radiation source and detector may be located vertically above and below the press. An electronic computer may be provided to indicate the density directly from the measured count. A body of known density such as an acceptable grinding wheel may be put into the press for calibration.