As the B 63-Committee had been set up in order to define the characteristics of a detonator audible in the driver's cab of any motive power unit, the first task undertaken by the Committee was to develop a technique suitable for measuring the explosive power of a detonator, both in the open air and inside a driver's cab. The assessments on detonators made up to the present were merely based on subjective comparisons. The Specialists on Acoustics of the SNCF and the DB who have done their work in mutual cooperation, rapidly designed a series of measurements, enabling, by means of cathodic oscillographs, the photographic recording of the variation in air pressure caused by a detonator explosion. It has been possible to confirm the subjective classification of the detonators in current use on the SNCF, the BR, the FS and the new DB-detonators, by recording the excess pressures produced; differences in audibility corresponded with relatively large divergent pressure ratios. It will henceforth be possible to compile technical manufacturing specifications to define the explosive power of a detonator by the magnitude of the excess pressure it should produce under given conditions. The tests conducted by the DB at Rosenheim in which SNCF, BR and DB-detonators were crushed by motive power units under normal traction conditions and during which subjective and physical methods were simultaneously used, have shown, as might be expected, that the sound insulation of the driver's cabs led to a reduced audibility of the detonators. With the exception of the new DB-detonator, no detonator any longer startled the staff, as was the case during steam traction. The fragmentation has so far proved to be the reverse of a high explosive force. Although an immediate improvement could be obtained by the adoption of another fastening method to the rail for the new detonator of the DB, it nevertheless remains true that too many metallic fragments are ejected by the body of this detonator itself.

  • Supplemental Notes:
    • Restrictions on the use of this document are contained in the explanatory material.
  • Corporate Authors:

    International Union of Railways

    Office of Research and Experiments
    Utrecht,   Netherlands 
  • Publication Date: 1962-10

Media Info

  • Features: Figures;
  • Pagination: 43 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00052930
  • Record Type: Publication
  • Source Agency: International Union of Railways
  • Report/Paper Numbers: B63/RP 1/E Intrm Rpt.
  • Files: TRIS
  • Created Date: Jul 8 1994 12:00AM