The Bottle, The Mould And The Vacuum

To complement the blowing process, the use of vacuum inside the mould has proved successful for the production of glass containers where even thickness of the walls is especially important, or where intricate shapes or designs are involved. Pressure inside the bottle can be quite a lot higher than that of the atmosphere. With regard to the production process for this kind of bottle,it is important that the thickness of the glass be even and compact all over the surface of the mould, so as to strengthen those areas considered to be "critical." This is in order to avoid stresses in the material that could give rise, literally to explosions. This article examines the technique and various type of vacuum pumps used in the operation.