DE1960279A1 - Process for the production of self-supporting structural elements and space bodies made of plastic - Google Patents

Description

136 (3278

Albert Pfleger

817 Bad Tölz / Obb.

Bahnhof str. 11

Tel. 08041/847

Process for the production of self-supporting components and space bodies made of plastic

The invention relates to a method of manufacture of self-supporting building elements and spatial structures Made of plastic * It is known to produce components and space bodies in the casting, blow molding or pressing process To manufacture plastic. In many cases, however, the mechanical or physical properties are sufficient of the finished component does not meet the requirements. That is why one has gone over to by combining plastics with other materials to achieve the desired properties achieve. For example, in the case of components made from cast resins, to a certain extent use of reinforcement through the incorporation of glass fibers or fiberglass fabrics.

To achieve even higher strengths, it is also already known to draw reinforcement threads made of metal or plastic into the glass fiber fabric layers and to connect these threads to one another by means of bow-like spacer threads. For high tensile loads, they must be made of metal, which in turn takes special measures against corrosive influences - e.g. sheathing or spinning - makes it necessary. An improvement the buckling strength of the finished component is neither due to the reinforcement threads nor the Distance threads reachable

Of particular importance are those on the use of glass fiber reinforced synthetic resins based manufacturing processes for the design of spatial structures with the lowest possible weight, but high load-bearing capacity, e.g. from boat hulls, car bodies, missiles, rocket parts ect., become · In the production of such spatial bodies, the so-called * hand lay-on process has become particularly popular introduced. In this process, an exact one must be selected from the body to be produced Positive or negative form are made, in or on which then the actual component is wallpapered in or on in layers up to the desired wall thickness

Since the production of the molds is time-consuming and expensive

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is, attempts have been made to develop methods for the production of space bodies that are without use get by with one form, for example a. procedure known, in which the desired body from -prefabricated, - thick foam plates, which as Filler, is put together by hand and then painted on both sides by means of a, sprayed on or on a spatula made of self-hardening plastic. To stiffen the entire body of the room, slots and holes are provided in the foam core, through which the self-sustaining art «· Fabric material can pass through during application and in this way stiffening pillars and ribs forms · Leave with this procedure however, neither exact dimensions nor high strengths can be achieved

Another well-known method is used; yourself one metallic inner framework, which is assembled from thin-walled lattice sheets, through its Holes the glass fiber reinforced resin layers placed on both sides are firmly bonded. the Use of the metallic, thin inserts brings an increase in tensile strength, but that's not the case the buckling and bending strength with it, and makes the advantage of the specifically light synthetic resin is negated again, also harbors the danger again the corrosion in itself and last but not least Difficulties arise which relate to the widely differing physical properties »such as» the expansion coefficient or the thermal conductivity of the interconnected materials metal and plastic, are based

The invention is based on the object of specifying a method for the production of self-supporting components and space bodies made of plastic, which, while avoiding the deficiencies inherent in the known methods, is characterized by simple handling without the use of molds, only uses materials of the same type and vsa construction elements or « Leads to spatial bodies that are extremely resistant to bending, kinking and torsion, meet high demands on heat and sound insulation and, if necessary, have buoyancy.

The invention is based on a method smr Her-

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position of self-supporting components and space bodies made of plastic, in which on an inner Framework glass fiber reinforced plastic, in particular cast resin, is applied.

The method according to the invention is characterized by the following method steps:

a) Plastic pipes, the diameter of which is a bit below the intended wall thickness of the finished component or spatial structure, are in parallel lined up fixed by spacers in the desired spatial arrangement

b) the outer surfaces formed by the plastic pipes are braided with fiberglass ribbons

c) the fiberglass tapes are impregnated with casting resin

d) the unfilled longitudinal channels still existing between the pipes are up to the level of the the envelope surface enclosing the plastic pipes is filled with absorbent filler on both sides, which is also impregnated with casting resin.

e) After hardening, the outer surfaces are leveled on one or both sides and covered with strips made of cast resin soaked fiberglass fabric covered

In the drawing, the invention is based on several Embodiments shown.

Xm individual shows:

1 shows the arrangement of the spacers in a boat hull in a perspective view partially inserted plastic pipes

Fig. 2 shows a spacer according to the invention for _t

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a hull with recesses to accommodate the plastic pipes

Fig. 3 is a partial cross-section through a finished boat wall

Fig. K shows a cross section through a after

Plate element manufactured according to the invention

Fig · 5 ^a is a cross-section through a further plate member with a different internal structure

Fig. 5b is a side view of the plate element

according to Fig. $ a with representation of the lateral edge delimitation

Fig. 6, a cross section through one after

box girders manufactured according to the invention

As shown in Fig, 1, for the production of a boat hull according to the inventive method, a certain number of spacers 1 in a h from the keel 2, the stem 3 and two Kimstringern existing form scaffold employed · The _β in Fig illustrated embodiment (Plattgattboot) the rear spacer is the stern post and mirror at the same time. The remaining spacers serve as form-determining frames. Since the method according to the invention achieves a considerable mechanical intrinsic strength of the boat wall, the high mechanical strength is reduced. Number of support frames, as is customary and necessary in conventional boat building, on the few spacers required for shaping. As shown in FIG. 2, they have recesses 5 on their outer edges, the depth of which corresponds approximately to the diameter of the plastic pipes to be inserted. If necessary, these spacers can at the same time have such an outline that the construction of cabin superstructures, in particular the cabin ceiling, according to the method according to the invention

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is possible (see Pig · 2). In the recesses 5 plastic pipes 6, which extend over the extend the entire length of the wall and due to their elasticity along any desired contour To achieve straightening lines, let it bend, insert and, if necessary, apply a suitable material Plastic glue held in place. As plastic pipes Commercially available PVC pipes can be used, which come in numerous dimensions and with different Properties are produced in large quantities and are therefore cheaply available

Since connecting sleeves or spigots are also on the market for pipes of this type, they need Processing practically no waste to be taken into account, which has a favorable effect on the manufacturing costs effects * The respective end ends of the pipes are either packed in sacks · » holes of the assigned stub or spacer inserted or fixed or glued in recesses using suitable fastening elements. Xn the molded framework obtained in this way, which because of the use of plastic pipes in addition to it achievable low volume weight of the finished boat wall also with regard to bending, kinking and torsion to exploit optimal properties of the pipe »cross-sections are now allowed according to the second process step of the invention Fiberglass ribbons 8 braided in such a way that together a fabric-like structure with the plastic pipes. arises in which the pipes correspond to the "weft thread" and the glass fiber tapes correspond to the "warp thread" ·

In the next step, the braided glass fiber tapes are used in a known manner Soaked in resin. After the cast resin impregnation has solidified, those that still exist between the pipes become unfilled longitudinal channels 9 up to the level of the plastic pipes enclosing on both sides Cover surfaces with absorbent filler (e.g. glass wool, rock wool, leftover waste from fiberglass tapes) the filler mass can also be embedded in plastic pipe sections with a smaller diameter after the resin-impregnated filler has hardened remaining air pockets are harmless Advantageously, the open

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Ends of all plastic pipes soaked by introducing them Filler sealed airtight. · The air pockets make unsinkable of the hull guaranteed.

After the filling zones have hardened, the resulting self-supporting walls are finally created on the outside, if necessary also on the inside, leveled and with one or several as required Coated layers 10 of fiberglass fabric sheets and casting resin. This measure is intended to except one additional increase in the overall strength of the The hull also serves to improve the impermeability and the surface treatment

Figure k shows a cross-section through a plate element, as it can be used, for example, for partition walls in the interior construction of buildings Plastic pipes 6b provided.

First, the pipes with the large diameter are installed and in the indicated course of the evenly dashed line with fiberglass tapes suitable width suitable for processing, braided and impregnated with resin. Afterward the mutually remaining deep longitudinal cavities 11 are each supported by a spacer filled with resin-soaked filler until the next and the plastic before it hardens tube β 6b (with a small diameter) inserted. Now the now empty longitudinal channels 9a and 9b filled with impregnated filling compound, leveled after hardening and, as required, with Cover layers 10 made of resin-glass fiber fabric laminate coated on both sides or on one side.

A second version of the creation of plate bodies according to FIG. K would provide for all tubes 6a and 6b to be installed in the first process step, the resulting tube frame in any variable manner - advantageously as indicated by reference numerals 8a, b "o in FIG. 4" with fiberglass bands zn

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interweave and. any remaining blank Level the longitudinal channels 9b by filling them with resin-impregnated filler. This version results in free cavities 11, as they are under certain conditions for wall construction elements are extremely desirable

Fig. 5a and 5b also show a plate-like Surface element with a structure similar to the process steps described above, with the difference that that here the spacers as spars, the plastic pipes on the front side in their fix the desired arrangement and position · The spars can be inserted into the finished part, as described above Cases that include internal spacers, or they serve only as a manufacturing device and are removed again after completion of the component

If wall elements are produced according to FIGS. 5 ^a 5 h, the front spar can advantageously be designed with a rabbet in order to achieve walls by positively lining up such structural elements, or to create walled rooms.

FIG. 6 shows a box girder produced according to the method according to the invention in cross section through the allocation of plastic pipes with the help of spacers in rectangular, square or any arbitrary Cross-section, together with the previously described operations of braiding, Soaking, filling and shifting, can every type and dimension of rigid beams and rigid columns can be produced «

In the serial production of components according to the invention, an » Application of well-known techniques such as dipping, spraying, extrusion and by Use of simple devices, such as clamping frames, pivoting pivot bars, tape pulling tools ect · achieve highly economical and yet very simple work processes.

Manufacturing can largely be done using

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unskilled and especially female workers are carried out »

The components produced according to the invention open up constructively a very broad field by looking at the advantages of the plastic material can make use of * In addition, such high mechanical strength values are achieved that, in the Relation to the resulting volume weight, measured using previously known manufacturing processes seemed impossible * Due to the air pockets related to the plastic material, which is inherently very favorable in terms of its physical properties, results in a Maximum level of sound and thermal insulation. When using the components produced by the method according to the invention within Construction projects have the option of laying all supply lines in the elements, namely along the pipe cavities. In the area of floating, propulsion and missiles is the achievable extremely high inherent elasticity of great importance.

Claims (10)

Claims Process for the production of self-supporting construction elements or spatial bodies, in which an interior Structural glass fiber reinforced plastic, in particular cast resin, is applied, characterized by the following process steps: a) Plastic pipes with a diameter slightly below the wall thickness of the finished component or Space body is arranged in parallel by spacers in the desired spatial arrangement fixed b) the outer surfaces formed by the plastic pipes are braided with fiberglass ribbons so that a fabric-like structure is created 1098 23/1616 1960273 c) the fiberglass tapes are impregnated with casting resin d) the unfilled longitudinal channels still existing between the pipes are one on both sides up to the height of the plastic pipes.
The closing envelope surface is filled with absorbent filler, which is also soaked with casting resin e) after hardening, the walls on both sides are leveled on one or both sides and covered with sheets of cast resin-soaked fiberglass fabric 10 9823/1616