Image Number 2 for United States Patent #4380186.
For the fabrication of pipeless explosive and/or propellant charges there is provided an insulation sleeve, whose radial thermal conductivity or heat transmission, at a random cross-section, essentially corresponds to the quantity of heat which radially flows out at such location and is released as a result of the solidification of the melt. By means of the insulation sleeve there is produced a pipeless casting without any subsequent supply of external or separate energy, e.g. electrical heating and so forth, even if the cast or molded article has very small pour openings. The required thermal conductivity or heat transmission in the insulation sleeve can be adapted to the thermal conditions of the cast article by employing insulating elements or parts and/or hollow spaces or chambers with heat carriers, e.g. melt. Corresponding casting methods are predicated upon a carefully directed preheating and stepwise cooling of the cast article and the insulation sleeve.