DE10010900A1 - Extrusion-pressing of high-impact, fuel tank blow-moldings, employs controlled blowing nozzle, core and separation strategy, followed by flange welding of shells formed - Google Patents

Abstract

A tubular preform (3) of defined length, is extruded from a perpendicular or horizontal adjustable nozzle (1). This is a round blowing nozzle with wall thickness control. Guides (4) spread the preform. A cutter (6) forms two curtains which are led over an internal core (11). Mold halves (7, 9) advance to form two shells with flange surrounds, by pressing. In an alternative, curtains are not formed, but the preform (3) is cut during pressing, along a plane of separation.. Mold stamps trim the shells; ejectors then extract them. The shells are welded together. An Independent claim is included for a machine carrying out the corresponding method. Preferred features: Before pressing, finished parts (15) are inlaid in reception recesses (16) of the core (11). They are welded precisely into place by the pressing process. During pressing, flanges are heated to welding temperature only on the core side. Remaining core and molding surfaces are cooled via bores. Following pressing, extraction and removal from the core, the shells are held firmly in the mold e.g. by suction. When they approach again, the shells are welded together by the sensible heat of their flanges, forming the finished container. When making vehicle tanks especially, an inner tank is laid into the lower shell. It comprises preferably two light, thin, deep-drawn sheet metal shells, connected diffusion-tight together. The sheet has a low tear strength and a precisely-located intentional rupture region, protecting against unacceptable internal pressure. The inner tank is fitted with parts such as a filling pipe, pump, level gauge and residue container. Connections to the inner tank are further detailed. Shell flange interior sealing faces, and tank openings, are metal-plated with an environmentally-acceptable, flexurally-resistant, sealed metal layer. A separate round section seal is included. The flange includes an O-ring groove, covered by plating. A suitable seal resisting effects of fuel, and diffusion, is inlaid. In an alternative, the seam is joined by immersion flow-soldering, during welding of the shells. Further variants based on the foregoing principles are described.

Description

The invention relates to a process for the production of all kinds of plastic molded parts, in particular containers, made of impact-resistant, blowable, thermoplastic, which are parts of the Blow molding and compression molding combined. This turns a conventional blow machine nozzle a tubular preform is pressed. This is divided into two curtains, which are then divided by Presses are formed and then mostly welded to the finished end product.

In the manufacture of parts from impact-resistant, thermoplastic plastic by blowing one limits to relatively simple forms. Through the usual blow nozzles with partial Wall thickness controls can also be used to form more complex parts. But to the Critical areas of a part must have sufficient wall thickness on less important points an unnecessarily high wall thickness can be accepted. share with Undercuts can only be done with great difficulty (DE 76-261 689) and often not reliable manufacturing. The deep drawing of pre-calendered flat material is also possible with the Blow molding used plastics possible. However, manufacturing is complicated Body contours not possible due to the lack of partial wall thickness control.

There are hardly any restrictions when it comes to injection molding, but the material must be be heated much higher, which makes the selection of the plastics used hard, brittle, low-viscosity meltable materials limited. The products are often under after spraying Tension, which can lead to tension cracks. Are due to the high pressures required Injection molding machines and injection molds are about four times more expensive than blow molding technology. While injection molds have to be milled from hard steel, blow molding can be cheap cast or milled from easily machinable aluminum.

This invention has for its object to parts of the blow molding and the press molding combine that even complicated parts with precisely defined wall thickness everywhere, as they have been could only be produced by injection molding, with machines adopted from the blow molding technology and shapes can be produced cheaper.

According to the invention, this object is achieved by the following method steps (claim 1):

• a) As shown in ( Fig. 1), the tubular preform ( 3 ) is ejected to a certain length from a normal, usually round extruder nozzle ( 1 ) with partial wall thickness control ( 2 ), such as is used for blowing. The preform ( 3 ) is spread by means of several spreading fingers ( 4 ) and, if necessary, cut into two curtains ( 5 ) with a heated cutting knife ( 6 ). ( Fig. 1a) shows the preform ( 3 ) cut with the separating knife ( 6 ) with a partial wall thickening ( 5 a). This is placed over a core ( 11 ) formed with the inside of the pressing body ( 9.1 , 10.1 ) so that the curtains ( 5 ) or the preform ( 3 ) do not touch the core. According to claim 11, the preform can be processed without cutting.
• b) The still plastic curtains ( 5 ) are then pressed by means of two mold halves ( 7 , 8 ) into two shells ( 9 , 10 ) with all-round flanges ( 12 ). The wall thickness at each point of the shells ( 9 , 10 ) can be precisely defined by the shapes on both sides. Only specific closing pressures of up to 10 bar / cm ^{2 are} required for the deformation, which is little, compared to the specific pressure of up to 500 bar / cm ² required for injection molding.
• c) As shown in ( Fig. 2), it is often advantageous for larger parts to eject the preform ( 3 a) horizontally, because it can not be stretched by its own weight or torn in extreme cases. Longer and large-area parts are easier to manufacture. The lower overall height of the machine, which becomes cheaper as a result, also speaks for this arrangement. In claim 13, a conveyor belt ( 4 c) for discharging the preform ( 3 a) is described. This arrangement enables the still plastic preform to be discharged smoothly. The core ( 11 ) is held on a rod ( 11.1 ) and moved into the curtain ( 3 ) in the correct position via the rollers ( 11.2 ) ( Fig. 2d). When the preform is not cut (3 a) in step a) in curtains (5) (Fig. 2e), the preform is cut (3a) during the pressing operation along the parting plane (12.1).
• d) As soon as the molded shells are closed, the protrusion is usually removed by means of a punch ( 13 ). After plastering and demolding, the shells ( 9 , 10 ) are processed further to form the finished body by means of ejectors ( 14 ) and removal from the press mold, preferably by welding the flanges ( 12 ).

Because of the shorter cooling time possible due to the cooling on both sides, the cycle times are shorter achievable and due to the defined, smaller wall thickness, the material consumption is reduced.

Installation of inserts

A particularly advantageous embodiment of this method is described in claims 2 and 3 ( FIG. 2c): Before pressing the finished body, parts ( 15 ) made of metal, plastic or overmolded metal parts ( FIG. 2f) can be inserted in receiving recesses ( 16 ) in the core ( 11 ) can be inserted, of course it is also possible to attach parts to the outside of the shells. The inserts are firmly and precisely welded to the shells ( 9 , 10 ) when the curtains ( 5 ) are pressed. They are not damaged by the heat of the preform because they are only heated on the welding surface ( 15.1 ), as shown in ( Fig. 2f). When inserting built-in parts into blow molded parts according to DE 196 00 872 A1, overheating the insert parts often leads to difficulties. ( Fig. 2a) shows a welded container with an inserted part ( 15 ).

Welding the shells

The welding of the shells ( 9 and 10 ) is described in claim 4: the core is heated in the area of the flanges, so that the inside of the flange ( 12.2 ) comes to the welding temperature. The remaining core and the outer mold halves ( 7 , 8 ) cool the shells ( 9 , 10 ) via the cooling holes ( 17 ) during pressing. The mold halves then move out of the area of the core, the shells being held in the mold halves by means of suction cups. When the mold halves are moved together again, the shells are welded to the flanges by their own heat. This configuration of the method makes repositioning and a separate welding machine superfluous. The cycle times can be shortened further if a second set of mold halves already presses the new curtains, while the first still welds the shells from the previous cycle.

( Fig. 2c) atypically shows the core in cross section with cooling / heat bores ( 17 ), pressed-on molded shells ( 9 , 10 ), ejector unit ( 14 ), waste punch ( 13 ) and receiving opening ( 16 ) for a laying parts ( 15 ).

( Fig. 2f) shows an example of an insert ( 15 ), which consists of plastic and / or metal, here according to the invention only the contact surface is slightly preheated, i.e. well below the usual 100 ° C in a gentle, dimensionally stable manner, and then in the Receiving opening inserted in the core / mold (with robot / manually). Due to the pressure, the connection to the container / tank wall is stronger than with previous blowing processes. (With conventional blowing of plastic parts, the whole part is usually preheated to approx. 100 ° C, which often results in warping in the mold.) The position in the core means that the part position is fixed, in contrast to the usual type, in which e.g. B. the remaining container is held in the air by means of a rod during the blowing process / form closing and is then ultrasonically welded in a second operation. The insert often slips, which leads to rejects.

Automobile tank

An automobile tank should have as much of the available installation space in the vehicle as possible fill out, this is possible with blown plastic tanks, but they are against the diffusion of Fuel components not tight enough. Tin tanks are very tight, but can only be difficult to adapt to the jagged installation spaces and are heavier.

Claim 5 shows an advantageous embodiment of the method according to the invention, which combines the advantages of both materials ( FIG. 3):
An inner tank ( 18 ) made of thin, less than 0.2 mm thick sheet metal is inserted into the plastic lower shell ( 9 ) and welded to the upper shell ( 10 ). Thanks to the easy deformability of the sheet-like sheet, the shells of the inner tank can be pressed into shape with the help of a water cushion and then sealed using suitable processes.

According to claim 6, the required system parts such as filler neck, pump, level sensor and residual containers must be installed beforehand.

So that the tank achieves the maximum tightness, the openings ( 20 ) of the sheet metal inner tank ( 18 ) are designed so that they protrude beyond the openings ( 21 ) of the plastic casing, which are cut out after the upper shell ( 10 ) has been pressed ( FIG. 3 ). The sheet metal or foil edges are flanged to form a flat sealing surface ( FIG. 3a). The tank is finally closed according to the system by a sealing ring ( 22 ), which is seated directly on the sheet or film, and a threaded cap ( 23 ).

The advantage of this configuration is that such a tank compared to metal tanks has increased security against sparking and explosions, especially if the inner tank is provided with predetermined breaking points. But it's lighter than a conventional plastic tank because the wall thickness can be shaped anywhere. At the same time, it has the diffusion density of a metal tank. The metal consumption is at most half as big, because there is only one kind of foil, which is much thinner than the normal tin tank is used. In addition, from previous metal tanks all built-in and add-on parts are taken over, they are on one Carrier sheet pre-installed in the inner tank. Since the plastic sleeve is not firmly attached to the metallic inner tank is connected, the materials can be easily recycled separate and recycle.

KKBs with a multi-layer wall structure are known.

Some manufacturers fluorinate or sulfonate their tanks internally, which does make them diffusion-tight increased, but has the effect that recycling is only possible for inferior products.

The thin fluorinated inner layer of such KKBs will meet future demands Diffusion tightness no longer. (DE 40 18 684 A1) uses a two-layer tank, the second However, layer only serves to increase the crash stability. KKBs can be coextruded with a multi-layer wall structure in one step. But these tanks can only be adapt even difficult installation spaces and / or have insufficient Diffusion tightness and a high weight (EP 0288 587 B1). Also a two-layer tank with fire extinguishing agent lying between the layers is described (DE 42 12 021 C1, DT 2359447 B2

3) However, due to its design, it is likely to be very expensive to manufacture. (Further Publications: DE 196 37 912 A, DE 196 07 250, DE 196 02 818, DE 196 50 244 A, DE 198 19 784 A, DE 196 51 652 A, DE 196 44 464 A, DE 198 02 078 A, DE 196 35 663 A, GB 02281726). On A two-layer tank with an external metal shell would be manageable, but quite difficult if it were should have the necessary mechanical stability.  

Manufacture of internally galvanized containers

By the method according to the invention it is also possible (claim 8), containers of all kinds inside to galvanize. The advantage over containers produced according to claims 5-7 is that easier production using methods that are common in plastics processing companies.

Claims 8, 9 and 10 indicate how the sealing surfaces of galvanized containers are connected in a diffusion-tight manner:
Conventionally with a flat sealing ring (claim 8, Fig. 4a), ( Fig. 5) shows a further connection by means of an O-ring ( 30 ) claim 9, which lies in the groove ( 30 ). Alternatively, the connection according to claim 10 is closed by immersion soldering of the flanges ( 12 ), a solder bath ( 25.1 ) being produced in the groove ( 28 ), into which the galvanically coated nose ( 27 ) is locked, a closed metallic connection ( 29 ) arises. ( Fig. 4) shows on the right the still open shells ( 9 , 10 ) with the coating ( 9.1 , 10.1 ), and on the left the shells with the finished groove soldering ( 29 ).

After blowing

Claim 12 shows a possibility (here called afterblowing) to minimize the loss of space in tanks consisting of two shells or other technical plastic parts, which is normally generated by the flanges. This takes place in that the two pressed but still plastically deformable shells ( 9 , 10 ) are transferred into two further mold halves ( 7 a, 8 a), the welding surfaces ( 12.2 ) being kept at the welding temperature. In the new enlarged form ( 7 a, 8 a), the welding surfaces ( 12.2 ) are first welded by means of flange slides ( 7 b, 8 b) that can be moved away laterally by pressing and at the same time the form is held closed. Then the remaining shell skin is blown fully into the expanded mold space ( 32 ) and molded into the final container, the plastic material on the cooled mold wall ( 9 a, 10 a) cooling and becoming dimensionally stable.

A further variant with the same machine elements can be designed such that the curtains are first pressed into shape only by means of the two mold halves and only in the area of the flange slide and then immediately afterwards the remaining preform wall is fully pressed into the remaining mold cavity ( 32 ) by means of blowing / pressing medium and there is cooled to two finished container shells, which is also possible with double blow molds. The slug is automatically punched on the closed form in a certain cycle, or later separated by hand. To demold the now undercut flange areas, simply pull out the flange slides ( 7 b, 8 b) with draft angles ( 7 b1, 8 b1) and remove the two shells from the mold halves for further processing. This process offers many other tank design options, e.g. B. galvanize the shells ( 9 , 10 ) and then provide the shells according to the options outlined in ( Fig. 4, 4a, 5) with openings for attachments. Installation groups can also be introduced beforehand or tin tank installations (FIGS . 3, 3a) can be carried out as described above.

Forming large parts by horizontal extrusion

Claim 13 ( Fig. 2, 2b) shows an inexpensive extrusion machine variant (nozzle ( 1 ) lies horizontally), in which the tube preform ( 3 ) is ejected instead of vertically horizontally, so that larger or longer shape or To be able to mold blow parts that would otherwise not be possible or could only be produced with great effort because of the existing blow nozzle height, locking frame height, hose length and, above all, too small a mold installation space. With long lengths, the hose weight often causes the preform ( 3 ) to tear off at the nozzle. The horizontal design would, in the case of large parts, without a discharge aid ( 4 c) according to the invention lead to the preform ( 3 ) collapsing at the nozzle, even if supporting air is added. In fact, horizontal blow molding machines are only known for small blow parts.

The design of the machine opens up a number of new variants: The insertion of the core ( 11 ) or of built-in parts ( 15 ) can, for. B. run obliquely or vertically. The core guide can also be taken over by other guide units, hydraulic / pneumatic cylinders which are state of the art, this is of course also possible with a different blowing nozzle position.

( Fig. 2b) shows a discharge aid in the form of a horizontal narrow heat-resistant conveyor belt ( 4 c) which runs synchronously with the hose ejection, for long horizontally ejected hose moldings, which are then used as required by means of the guide elements ( 4 a, 4 b) (also spreading fingers called) spread over the mold opening and vertically and / or horizontally so that the inner mold core ( 11 , Fig. 2d) or in the pure blow part according to claim 14 insert parts (e.g. Fig. 2f part 15 ) can be inserted without hindrance, before the two molded shells ( 7 , 8 ) close.

In ( Fig. 2d) a horizontally retracting atypical core ( 11 ) is symbolically shown, which on a horizontal z. B. as a prism profile ( Fig. 2e) executed guide bar ( 11.1 ), which is inserted by at least 3 prismatic guide rollers ( 11.2 ) in the correct position (see arrow) in the tube molding ( 3 ).

The same advantages as described above can be larger according to claim 14 for blowing to use most of it. The missing core makes this arrangement even cheaper. And how too in extrusion pressing according to claim 13, the shapes can be made much easier here change, which is particularly important for small series.

Manufacture of parts with undercuts

Claim 15 (FIGS. 7, 7a, 7b) describes a variant of the invention in which the tubular preform ( 3 ) is cut open to form a curtain ( 5 ), then separated from the blow nozzle with the heated knife ( 6 a), by means of a carrying device ( 4 a, 4 b) placed in the horizontal and then pulled over the horizontal, divisible core ( 33 , 33 a), in order to then with the descending mold outer shell ( 32 a), the laterally closing slides ( 34 , 35 ) z. B. to be pressed into a bumper ( Fig. 7c). A dashboard (with a soft / or other lamination material or insert that is inserted into the outer form, which is also welded on at the same time) and with openings punched out in the pressing process, fenders, engine noise insulation hood, body parts with threaded insert parts, or the like can be formed in this way.

The mold, the divided core ( 33 , 33 a) and the side slides ( 34 , 35 ) have bores ( 17 ) for cooling / tempering the molded parts. A waste punch ( 36 ) for plastering the molded parts is arranged on the outside along the mold contour, so that the molded parts can be removed from the mold ( 32 ) as ready for installation as possible. This type of production was previously only possible with GRP presses or spraying technology, but they were much more expensive and / or could not be used for containers / interior parts in the automotive industry. Because of the poor flow properties in the extruder, in the sprue and not least in the injection mold, the impact-resistant thermoplastics can only be processed inadequately or not at all in the injection molding process.

The method according to the invention offers many new and still unknown manufacturing and Product design options.  

Explanation of symbols

(

Fig.

1)
Round nozzle (

1

)
partial wall thickness control (

2

)
Preform (

3rd

)
Guide elements (

4

)
Curtains (

5

)
Cutting device (

6

)
(

Fig.

1a)
(

Fig.

2)
Press body insides (

9.1

,

10.1

)
Core (

11

)
Mold halves (

7

,

8th

)
Bowls (

9

,

10th

)
Flange (

12th

)
Parting line (

12.1

)
(

Fig.

2)
Form punch (

13

)
Ejector (

14

)
Inserts (

15

)
Wells (

16

)
Shell inside (

9.1

respectively.

10.1

)
Recesses (

16

)
Welding area (

12.2

)
Cooling holes (

17th

)
Mold halves (

7.8

) Mold halves (

9

,

10th

)
(

Fig.

3)
Lower shell (

9

)
Inner tank (

18th

)
Oberschhale (

10th

)
finished plastic hollow body (

19th

)
deep-drawn sheet metal shells (

18.1

,

18.2

)
Sheet of the shells (

18.1

,

18.2

)
(

Fig.

4)
Openings (

20th

) of the sheet metal inner tank (

18th

)
(

Fig.

3a)
Plastic shell opening (

21

)
Stand out (

20.1

),
Sheet edges (

20.1

)
Sealing ring (

22

)
Threaded cap (

23

)
Plastic shell opening (

21

)
Thread (

24th

)
Metal layer (

25th

)
Poetry (

26

)
(

Fig.

4a)
Electroplating layers (

25th

) Metal layer (

25th

)
circumferential nose (

27

),
Soft solder (

25.1

)
lower electroplating layer (

25th

)
filled groove (

28

)
finished soldering (

29

)
Diving plumb (

25.1

)
(

Fig.

5)
O-ring groove (

30th

)
O-ring (

31

)
extended mold cavities (

32

)
(

Fig.

2),
(

Fig.

2 B)
Discharge direction (A)
Slide rail (

4

a)
Jet (

1

,

2

)
Preform (

3rd

a)
Inside of the hose (

3rd

a)
Slide rail (

4

a)
Conveyor belt (

4

c)
Hose (

3rd

a)
(

Fig.

6)
further inflation form (

7

a,

8th

a)
Release valve (

7

b

8th

b)
with enlarged contour (

9

a,

10th

a)
extended mold cavities (

32

)

Claims (15)

1. Combined extrusion-pressing process for the production of bodies and hollow bodies with a defined wall thickness from a blowable, impact-resistant plastic, characterized by the following process steps:

• a) The tubular preform ( 3 ) produced by extrusion from a preferably vertical ( Fig. 1) or horizontal ( Fig. 2) standing extruder nozzle ( 1 ), preferably a circular blow nozzle with partial wall thickness control, is by means of several guide elements ( 4 ) spread, if necessary cut into mostly two curtains ( 5 ) by means of a cutting device ( 6 ) ( FIG. 1a) and guided in a contact-free manner via a core ( 11 ) formed with the inside of the pressing body ( 9.1 , 10.1 );
• b) the curtains ( 5 ) are then pressed by means of at least two mold halves ( 7 , 8 ) to at least two shells ( 9 , 10 ) with preferably all-round flanges ( 12 );
• the preform (3) in step c) has a not cut) in curtains (5), the pre will molding (3) during the pressing operation along the parting plane (12.1) is cut; ( Fig. 2)
• d) the shells ( 9 , 10 ) are further processed after plastering by means of a punch ( 13 ), demolding by means of an ejector ( 14 ) and removal from the press mold, preferably by welding the flanges.

2. The method according to claim 1, characterized in that parts ( 15 ) are inserted into receiving recesses ( 16 ) of the core ( 11 ) before pressing the finished body. 3. The method according to claim 1 and 2, characterized in that the parts ( 15 ) are held during the pressing in the preformed recesses ( 16 ) of the core ( 11 ) and welded there on the inside of the shell ( 9.1 or 10.1 ) by the pressing process in a precise position become. 4. The method according to claim 1 to 3, characterized in that during the pressing the flanges ( 12 ) on the core side only in the welding surface area ( 12.2 ) locally heated by means of temperature control to the welding temperature, while the remaining core and mold surfaces via cooling bores ( 17 ) be cooled; After pressing and demolding the core ( 11 ), the shells ( 9 , 10 ) are held firmly in the mold halves ( 7.8 ) by means of suction cups or other suitable holding means, after which the core ( 11 ) or the mold halves ( 9 , 10 ) are moved away, so that the shells ( 9 , 10 ) are welded to the flanges ( 12 ) by their own heat to the finished container when moving together again. 5. The method according to claim 1 and 2, characterized ( Fig. 3) that in particular for vehicle tanks in the lower shell ( 9 ) an inner tank ( 18 ) is inserted, which is assembled with the upper shell ( 10 ) to form the finished hollow body ( 19 ) , preferably by welding; the inner tank preferably consists of two light, thin, deep-drawn sheet metal shells ( 18.1 , 18.2 ), which are connected to one another in a diffusion-tight manner. The sheet of the shells ( 18.1 , 18.2 ) has a low tensile strength and a precisely placed predetermined breaking point against inadmissible internal pressure 6. The method according to claim 1, 2 and 5, characterized in that the sheet metal inner tank ( 18 ) is equipped with system parts such as filler neck, pump, level sensor and residual container. 7. The method according to claim 1, 2 and 5 to 6, characterized ( Fig. 3) that the openings ( 20 ) of the sheet metal inner tank ( 18 ) from the plastic shell opening ( 21 ) protrude so far ( 20.1 ) so that after the flanging ( Fig. 3a) of the sheet metal edges ( 20.1 ) a diffusion-tight closure is preferably possible ( Fig. 4) by means of sealing ring ( 22 ) and threaded cap ( 23 ) which is screwed onto the thread ( 24 ) formed on the plastic shell opening ( 21 ). 8. The method according to claim 1 and 2, characterized ( Fig. 4a) that the separately shaped shells ( 9 , 10 ) on their inner sides ( 9.1 , 10.1 ) and the sealing surfaces of the flanges ( 9.1 a, 10.1 a) and tank openings ( 21 ) galvanized with a fuel-resistant, environmentally friendly, bending-resistant, dense metal layer ( 25 ) and sealed by means of a seal ( 26 ), whereby the production of a diffusion-tight, lightweight hollow body, in particular vehicle tanks, with a defined wall thickness is possible, but this is compared to conventional ones fluorinated tanks have a thinner wall; 9. The method according to claim 1, 2 and 8 ( Fig. 5), characterized in that the flange ( 12 ) is provided with at least one O-ring groove ( 30 ) and the electroplated layer ( 25 ) covers the O-ring groove ( 30 ) . Diffusion-tightness is ensured by an inserted diffusion-tight and fuel-resistant round sealing ring ( 31 ). 10. The method according to claim 1, 2 and 8, ( Fig. 4a), characterized in that the two so-called galvanic layers ( 25 ) (from above and below) are connected simultaneously by immersion soldering (see x) when welding the plastic shells. This is achieved in that a small circumferential nose ( 27 ), which separates the upper electroplating layer ( 25 ) from the flange welding surface ( 9.1a ) but is also galvanically coated, which vertically into a liquid soft solder ( 25.1 ) (the lower electroplating layer ( 25 ) the groove ( 28 ), which is circumferentially touching), is immersed in parallel with the welding of the two welding flanges and moves downwards into the plunge solder ( 25.1 ) and thus connects the two electroplating layers ( 25 ) in a diffusion-tight manner. 11. The method according to claim 1, characterized in that the preform ( 3 ) without cutting from the extrusion nozzle ( 1 ) is separated, discharged from the extruder and pressed in a separate press machine adjacent to a housing or container part. (without drawing) 12. The method according to claim 1 to 3 ( Fig. 6), characterized in that during the pressing the flanges ( 9.1 a, 10.1 a) are heated to the welding temperature on the core side, after pressing and demolding from the core ( 11 ) and out the shells ( 9 , 10 ) are removed from the original mold halves ( 7 , 8 ) and inserted into an adjacent inflating mold ( 7 a, 8 a) with an enlarged contour (9% 10a), which is inserted at the flange area and protrudes into the mold cavity De-molding slide ( 7 b, 8 b) has; when the inflating mold ( 7 a, 8 a) moves together, the shells ( 9 , 10 ) are first welded to the flanges and then immediately blown (stretched) into the finished container by means of a pressure medium, preferably compressed air, into the expanded mold cavities ( 32 ); this is particularly advantageous in the case of complicatedly curved tank proboscis with retaining tabs, water and brake fluid containers and other complicated technical hollow bodies with sufficiently well-defined internal dimensions. Also in cases where the installation space (especially in car construction) should be used as fully as possible and therefore loss of filling volume due to the welding flange should be avoided. 13. Machine for performing the method according to claim 1a ( Fig. 2), characterized in that at approximately horizontal ejection of the preform ( 3 a) of the preform on at least one top of the inside of the tube ( 3 a) in the ejection direction (A ) arranged slide rail ( 4 a) slides out of the nozzle ( 11 , 2 ). To reduce the friction ( Fig. 2b), this slide rail ( 4 a) from a narrow conveyor belt ( 4 c), which runs synchronously with the speed of the tube ( 3 a), or from other conventional linear units. 14. Machine according to claim 13 for performing the method according to claim 1a (Fig. 2d, 2e), characterized in that the preform ( 3 ) is held by the slide rail ( 4 a) and a strong vacuum in the mold halves, and the mold halves close without a core ( 11 ) in between, then the slide rails ( 4 a, 4 b, 4 c) or other linear units are removed while compressed air (supporting air) is already blown into the preform ( 3 ). The locked preform ( 3 ), which does not protrude beyond the longitudinal cutting edges, is then blow molded to the finished part in the usual way. 15. Machine for performing the method according to claim 1 ( Fig. 7), characterized in that the preform ( 3 ) after ejection to two or more curtains ( 5 ) cut and by means of holding devices ( 4 a, 4 b) in the horizontal position brought ( Fig. 7a) over the divisible core ( 33 , 33 a), which removes the undercuts, held and then by means of the outer shape ( 32 ) and the side sliders ( 34 , 35 ) for example to a bumper, fender, engine noise damper hood, body part ( with inserts, e.g. threaded sleeves), dashboard (also with soft material and thus concealed shock-absorbing outer skin and inserts) and so on. Mold, core and slide have holes and / or heating elements for temperature control. The slug protrusion is removed from the pressed part by means of a waste punch ( 36 ).