Method for the manufacture of a bung barrel with a side wall, bottom and cover.

The invention relates to a bung barrel with barrel casing, barrel bottom and barrel top, which are integrally molded through blow molding of thermoplastic material, wherein the barrel top has at least one bung with bung hole collar and being arranged an L-ring in the region of the transition between the barrel sidewall and the barrel top for manipulation purposes is. The invention henceforth concerns a method for producing such a bung barrel. L ring means that the ring has an inverted L-shaped cross section in upright bung barrel, whose L-foot points outwards. L-legs and L-foot may be connected at right angles or at a different angle to each other. The L-ring may be molded in the blow-molding or pre-formed and welded.

Bung barrels of the construction described are used as containers for various purposes and for the storage and transport of a wide variety of liquid substances. The practice requires increasingly tight head drums, which can be as completely emptied with little remaining in the bung barrel residual amount. For Zwekke emptying such a plugged vessel is brought into a Entleerungskippstellung Angled Faßachse or asked to speak with vertical Faßachse upside. This latter position is referred to in the invention as inverted, emptying position. It is at least taken at the end of emptying process. In general, two bung holes are provided, one. For the filling, one for the emptying The filling can also be done through both bung holes. Emptying through a defined bunghole. It is understood that the evacuation is carried out so that the leakage of the liquid air can penetrate into the plugged vessel. The bung barrel can be to also equipped with appropriate facilities. The bunghole collar is externally usually provided with a thread for screwing on a closure cap.

Within the known measures of which the invention is based (DE-GM 86 28 811) the bunghole and bunghole collar are formed in the blow molding. Usually forms of hose thermoplasticized plastic that is blown in the blow mold, the bunghole collar. However, the bunghole collar can also be configured as a protuberance that is formed during the blow molding and the top head is cut off after molding, so as to form from the hat-shaped protuberance of the bung hole collar. Both during the emptying of a bung barrel by a Entleerungskippstellung as well as during emptying of a bung barrel on the inverted, emptying position is a troublesome large residual amount of the known bung barrels. A full evacuation by mere expiry, after which in the plugged vessel one disturbing large amount of liquid to be emptied no longer exists, is not possible. If the plugged vessel to be used again, be filled esp. With another liquid substance, the remaining quantity must be laboriously removed and discarded. The cleaning of Faßinnenraumes is difficult when there is still a disturbingly large residual amount in Faßinnenraum.

The invention is based on the object, so on form a bung barrel of the structure described above that in the inverted, emptying position a full evacuation without disturbing remaining amount is possible. The invention is henceforth an object of the invention to provide a method with which such a bung barrel can be manufactured in a simple manner.

To achieve this object, the invention teaches that the bunghole is designed as a bore hole, which is arranged in a lowest in the inverted, emptying position area of ​​the barrel top, and that the bung hole collar welded formed as a preformed part with welding flange and externally with the weld to the barrel top is. The preformed component generally consists of a thermoplastic plastic material which is easily weldable to the plastic from which the barrel sidewall, barrel bottom and the barrel top which are constructed. According to a preferred embodiment of the invention, the preformed component has an internal diameter which virtually corresponds to the borehole diameter. but also it will not interfere when the inner diameter of the preformed component is a little larger or a little smaller than the borehole diameter. - The invention is based on the realization that in the area between the barrel top and bung sleeve for Faßinnenraum out of rheological reasons the bunghole surrounding, more or less pronounced bulge occurs when, the bunghole collar is formed from the thermo-plasticized tubing as described above from which the barrel is blown, or if the bunghole collar by means of a protuberance is formed. This more or less pronounced ridge has not been recognized, little noticed or taken as not interfere in purchase. The bead actually interferes little when the bunghole connected to the barrel casing and the plugged vessel is brought to discharging to Entleerungskippstellung. However, modern practice requires the full emptying on the inverted, emptying position. Then, the peripheral bead forms a wall, behind which, depending on the bead thickness is a very significant, disturbing large residual amount of liquid to be emptied accumulates and accumulates. A full emptying is not possible in such a case. According to the invention, such a circumferential bead is avoided because the bunghole is produced as well. The term borehole is intended to express that the hole is cut. In this case with a conventional drill, a correspondingly guided mechanical knife, a knife used as a laser beam o. The like. To work.

Specifically, there are several possibilities of further development and design of the bung barrel in the invention. Thus, an embodiment is characterized in that the deepest position in inverted, emptying the region of the barrel top is arranged in the center of the barrel top. Another embodiment is characterized in that the deepest position in inverted, emptying the region of the barrel top is designed as a circumferential, shallow channel at the edge of the barrel top. However, it is also possible to make the arrangement such that the barrel top is designed as an inclined plane and the well is placed in the deepest position in inverted, emptying the region of the inclined plane.

As already mentioned, a plugged vessel is generally provided with two bungholes. The second bung is arranged in an inventive bung barrel outside in Entlee approximately inversion position the deepest portion of the barrel top. According to the invention the second bunghole is expediently carried out as well and welded the bunghole collar with a weld.

In the manufacture of a bung barrel according to the invention it is possible to weld the bung-hole collar to the demolded, finished in the rest bung barrel. A preferred embodiment of the invention is characterized in that the bung-hole collar in the form of a pre-formed component made of thermoplastic material, which has a welding flange, is inserted into the blow mold and welded in the blow molding of the barrel top is and that the blow hole is introduced after the removal of the bung barrel , Characterized by simplicity in terms of process technology is an embodiment in which the preformed component is inserted into the blow mold to surround the blow hole formed during the blow molding, which is chosen to be less than that which corresponds to the inside diameter of the bunghole collar, and that the range of barrel top between blowhole and bunghole collar is removed after removal by drilling. If it is the manufacture of a bung barrel with two bung holes, it is recommended that the pre-formed components for both bung holes into the blow mold are inserted.

The invention is explained in more detail, reference being made embodiment drawing depicting. Shown in a schematic representation<ul><li>FIG. 1 shows an axial section through an inventive bung barrel, </li><li>Fig 2 in comparison with FIG. 1 greatly enlarged scale the detail A of the article of FIG. 1,</li><li>Fig. 3 in the left part of the further enlarged detail B from the article of Fig. 2 and in the right part, a corresponding representation of a known embodiment,</li><li>Fig. 4 corresponding to Fig. 1, another embodiment of a bung barrel according to the invention,</li><li>FIG. 5 corresponding to FIG. 1 a further embodiment,</li><li>Fig. 6 is a side view of yet another embodiment, partially in vertical section,</li><li>Fig. 7 shows the enlarged section A from the article of Fig. 6 and</li><li>Fig. 8 is a plan view of the article of Fig. 7.</li></ul>

The bung barrel illustrated in Figures 1 to 5 has a barrel sidewall 1, a barrel bottom and a barrel top 3. 2 the bung barrel has been formed in one piece by means of blow molding of thermoplastic material. The barrel top 3 has in the exemplary embodiment two bungs 4 with bunghole collar 5. arranged in the transition area between the barrel sidewall 1 and barrel top 3 is an L-ring 6 for manipulation purposes. Esp. from a comparison of FIGS. 1 and 2 takes it that the bunghole 4 is designed as a drilled hole, which in an in the purge is arranged ungsinversionsstellung deepest region of the barrel top third In the inverted, emptying position would be upside down in Figs. 1 and 4 and 5 barrels of vertical axis shown. The bunghole collar 5 is designed as a pre-formed component with weld. 7 The preformed member is welded from the outside with the welding flange 7 to the barrel top third It may also consist of plastic and has an inner diameter as closely as possible matches the hole diameter. - Through the borehole and the design described the formation of a bead is avoided, which occurs when the bung-hole collar 5 is formed during the blow-molding from the thermoplasticized hose which is inflated in the blow mold to the bung barrel 1, 2, 3, or when the bunghole collar 5 is made ​​as a protuberance in the blow molding. Reference is made ​​to FIG. 3. In FIG. 3 the left can be seen as an enlargement of the subject of FIG. 2, the embodiment of the invention, in which Fig. 3 right the bead 8. As described in the known embodiments already explained, makes this bead 8 in the inverted, emptying position as if a dam who holds a disturbing amount of the emptied liquid substance.

In the embodiment of FIG. 1 is the deepest in inverted, emptying position area of ​​the barrel top 3 is in the center of the barrel top 3. In the embodiment of FIG. 4, the configuration is devised such that the deepest in inverted, emptying position area of ​​the barrel top 3 as a circumferential groove 9 am edge of the barrel top is performed. 3 In Fig. 5 it can be seen that the barrel top is designed as an inclined plane 3 and that the bung-hole 4 is placed in the deepest position in inverted, emptying the region of the inclined plane. In the embodiment, the bung barrel 1, 2, 3 and a second bunghole has always 4. The second bunghole 4 is designed as a borehole and the bunghole collar 5 is welded as a pre-formed component with a weld. 7

The embodiment according to FIGS. 6 to 8 differs from the embodiment according to FIGS. 1 to 5 characterized in that the bung-hole collar 5, which is a pre-formed component, an outwardly projecting welding flange does not have. The arrangement is rather made so that the bunghole collar 5 an extension 5a has, projecting into the Faßinnenraum and their outer diameter in the borehole diameter and thus fit in the diameter of the bunghole 4. The bunghole collar 5 is welded to the extension 5a in the barrel top. 3 In the extension 5a full emptying holes 5b are arranged. The barrel top 3 has, based on the emptying of the tilted or 180 ° C twisted barrel, a lowest point and the deepest the bunghole 4 of the bung hole collar. 5 Full draining holes means that as it faßinnenraumseitig in the extended bunghole collar 5a these holes are arranged 5b that touch the inner surface of the barrel top. 3 Reference is made in particular to Figures 7, which shows that a very complete emptying is possible.