Abstract: A container (30d) of polyethylene terephthalate or similar thermoplastic material has a container body (32d), a mouth portion (37d) and a central bottom part (34d). The central bottom part consists of chiefly amorphous and/or thermocrystallized material and forms a bulge directed towards the interior of the container. A ring-shaped or band-shaped standing surface (36d) is arranged adjacent the transition of the bottom part into the container wall (32d). Adjacent to the standing surface the container has a circumferential area of material (35d) which by stretching and/or reshaping has undergone flow and by heating has acquired built-in stresses which tend to contract it. The surrounding circumferential area of material prevents the inward bulge of the central bottom part from straightening out and/or turning inside out when the pressure in the container is increased and/or when the temperature of the container material is raised.

Abstract: A method of forming a preform having crystallized thermoplastic material from a blank of orientable thermoplastic material, such as polyethylene terephthalate, which comprises laterally displacing first and second regions of a blank, preferably tubular, of orientable thermoplastic material to form an intermediate region between the displaced regions having outer surfaces facing in opposite directions. Pressure is applied to the outer surfaces of the intermediate region to relatively displace these outer surfaces longitudinally of the blank while concurrently reducing the thickness of one of the first and second regions to the value of the thickness that the material would obtain if freely stretched to flow to achieve crystallization of the material in the aforesaid one region. The material in the one region, during the reduction of thickness thereof flowing from the orientable material thereof to a transition zone to form the one region which is reduced in thickness and is elongated in length.

Abstract: A method of producing a container of polyethylene terephthalate or similar thermoplastic material from a tubular blank of amorphous material. A mechanical forming element moves a transitional zone between amorphous (thicker) material and thinner oriented material stretched to flow during simultaneous elongation of the blank in the direction of movement of the transitional zone. The stretched and oriented material is heated to a temperature higher than the temperature of the material immediately before stretching. As a result, the internal stresses produced in the material during earlier stretching are relieved. Heating causes the length of the material in the direction of stretching also to be reduced. Each subsequent forming stage for shaping the container takes place at a temperature lower than the temperature at the immediately preceding forming stage.

Abstract: A mold, for forming a container by fluid pressure, having two mold halves and two axially movable plungers, the plungers forming the bottom of the container therebetween, an inner plunger or mandrel having a concave end and a second plunger, hereafter called "the bottom part", having a convex end.

Abstract: A device for recovering salvagable components from a mixture of compacted solid waste, especially municipal waste, which includes ferrous metals, non-ferrous metals such as aluminum, fibrous organic and inorganic materials. In this installation the solid waste, preferably after first breaking it up, is fed to a magnet assembly for dividing the components into ferrous metals and non-ferrous materials including ferrous metals and non-ferrous metals and organic or inorganic materials. The ferrous metals and the non-ferrous materials containing ferrous metals are then subjected to fragmentation after separating ferrous metals parts from non-ferrous materials. The resulting fragments are separated into ferrous metals and non-ferrous materials and separately conveyed to collection stations. Similarly, the non-ferrous metals and the organic or inorganic materials are first fragmented, then separated from each other and finally separately conveyed to collecting stations.