Patent Number: 055679528
Section: description

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 3 shows a container with a non removable base in accordance with the present invention. FIG. 3a shows an enlargement of the base--tube interface. FIG. 3b shows a detail of the base--tube interface in the particular instance where the base is recessed within the base. Reference numerals 1, 2, 3, 4, 5, 6, 8, 10, 18, 19 have the same meanings as in FIGS. 1 and 2 of the prior art. Base (6) is located inside tube (1), of steel or other strong metal, and has a peripheral lateral wall (12) which is cylindrical with a circular cross section and is enclosed over its entire height by an identical cylindrical portion (13) machined in the internal wall (20) of tube (1). In the figure, the external surface (14) of base (6) does not extend beyond the plane containing the end face (10) of tube (1). Base (6) is then held in place by shrink fitting using the tube (1) itself. The cavity (22) of the container can be of any shape (for example with a polygonal cross section) such that its internal wall (20) requires a countersink (21) (FIG. 3a) to hold the base in place while other cavity (22) shapes (for example a circular cross section) would not require this countersink (see FIG. 3, 18a). The following can also be seen: the external weld seem (17) connects the peripheral edge of the external surface (14) of base (6) to the tube; PA1 the internal weld seam (18, 18a) which connects the peripheral edge of the internal surface (19) of base (6) to the tube; and at (18a), the internal wall (20) of the cavity has no countersink (as described above). Two cooperating shoulders (15) can also be seen, one machined in the inner wall of tube (1) and the other in the lateral (12) of base (6). It can be seen from FIG. 3b that the external surface (14) of base (6) is not flush with the end face (10) of tube (1), but is within it: this forms a circular disk which can, for example, be used to hold additional incompressible neutron shielding (23). The sealing weld (17) thus connects the external surface (14) of base (6) to the internal surface of tube (1). It should be noted that it could be advantageous to provide an allowance for assembly between base (6) and tube (1) in the vertical larger diameter portion (arrow 13) from the shoulder and it is preferable that this portion is of reduced height with respect to the smaller diameter portion (arrow 12). This is preferably sufficient to hold the base (6) in place even if it forms no part of the secure shrink fitting. It should also be noted that, as described above, the countersink (21) of the tube can be partially or completely absent over the internal surface of the tube and may or may not coexist with shoulder (15). It may also replace shoulder (15).