DE10245284A1 - For the production of wood blocks, from an extruded strand of compressed and glued wood particles/chips, the wood material is heated on entering the filling/press zone of the extrusion press - Google Patents

Abstract

For the production of an extruded strand of wood material, the wood particles and chips together with a liquid or powder glue are fed into the extrusion press to be compressed and bonded. The material is pressed into a reactor zone (214) where water is applied as steam or hot water to activate the glue together with a hardener. The wood particles/chips are heated to a higher than usual temperature in the filling/press zone (197), from 50 deg C to \-90 deg C. The condensation from the reactor is extracted to be passed through a cleaning stage, and the wood strand passes through a compression channel, where pressure is applied by a series of double-action cylinders (200). The compressed material is cut by saws into blocks.

Description

Method and device for extruding and extruding small parts, in particular Small wooden parts for e.g. B. pallet blocks.

The invention relates to a process for the production of strands from small parts, in particular small wooden parts with binders, from which pallet blocks are cut, in which the small parts are wetted with the glue in powdery or liquid form after drying at a temperature of approximately 90 ° C. reach the filling and pressing chamber of an extrusion or extrusion tube press, compacted in it and transported to a reactor and charged with a mixture of hardener and H ₂ O in vapor form or evaporating water, the H ₂ O on the one hand being a component of the glue can form and on the other hand for further strand heating and the glue begins to set through the hardener and then the strand is brought into a tempered setting channel, sets in it and the condensed H ₂ O with the volatile glue components such as urea, formaldehyde, methanol, acids, salts and ammonia escapes from the skein that this r a partial vacuum can be applied through an injection condenser, whereby the condensate can be subjected to a subsequent cleaning treatment and the set strand can be cut into pieces in a moving saw following the setting channel, or can be cut into finished pallet blocks.

In the extrusion process, pallet blocks have so far been made according to the process DE 29 32 406 Combined with a heating duct according to DE 25 35 989. These presses are supposed to now by PCT / EP / 99/00558; PCT / EP / 00/04852 and / or. PCT / EP / 06872 be modernized or replaced. Compared to the former, technically outdated However, processes offer only limited solutions to the second-mentioned processes Advances and even significant disadvantages in energy requirements.

The compression is carried out in the above-mentioned processes by means of a press ram, which also includes a continuous, hollow-bored piston rod. When extruding pipes is guided through the piston rod bore in the longitudinal direction fixed mandrel. The Dorn increases friction and reduces the ability to control the density of the strand. The presses mentioned are therefore very sensitive and easily stuck.

The filling in presses according to DE 29 32 406 is done by a closing slide according to DE 28 10 071 with preferably 3 double strokes. This takes an ample 3 s. The Teachings from PCT / EP / 99/00558 do not offer any noteworthy compared to DE 28 10 071 Progress.

The curing channels used according to DE 25 35 989 require a high heat requirement of up to about 220 kcal / kg strand and heat the strand only at a speed of about 11 s / mm strand thickness. The inadequate heating rate should be with PCT / EP / 00/04852 and / or. PCT / EP / 06872 can be increased. However, the latter methods require a considerably higher energy and do not teach how the H ₂ O condensed in the strand can be removed again.

In the above-mentioned processes, the small wooden parts are first dried in a dryer Dried down 2% dry since the presses do not process chips with higher moisture can. In intermediate bunkers they cool down to about 25 ° C to almost 50 ° C and become mixed in a mixer with the finished melamine glue and hardener. The cooling is required to avoid pre-setting the glue.

The set, hardened strand is in a moving after the setting channel 4-blade saw sawn into pallet blocks. The saw's performance is less than 500 Cuts / hour.

Overall, the above teachings have the following major shortcomings:
The small parts have to cool from a temperature, which is usually well above 100 ° C after the dryer, to 25 ° C to about 50 ° C and then have to be heated again in the setting channel to a setting temperature of up to over 100 ° C.
The piston rods of the press rams are subject to shear forces, which are caused by the mandrel and the insufficient filling. As a result, the service life of the guides, seals, piston rods and mandrel sleeve is limited to a few weeks to a few months. An increase in speed is therefore hardly possible.
Filling takes up most of the time in the press cycle.
The curing time can be adjusted with PCT / EP / 99/00558; PCT / EP / 00/04852 and / or. Although PCT / EP / 06872 can be significantly reduced, the water contained in the strand can only be used to produce a usable pallet block if so much steam is supplied from the steam station that the water condensed in the initially cool strand largely evaporates again.
In relation to the production of chipboard, the energy requirements for the processes mentioned are too high.
The continuous output of the devices according to DE 29 32 406 is currently 27,000 to 30,000 blocks in 24 hours. Also when using PCT / EP / 99/00558; PCT / EP / 00/04852 and / or. PCT / EP / 06872 the output can hardly be increased to over 50,000 pallet blocks / day at a height of 78 mm.

With DE 41 17 659, PCT / EP / 9901988, OS DE 100 59 443 A1, EP 0339 497 B1, EP 0 376 175 and DE 101 01 823 A, methods and devices were known which, in their respective task area can significantly increase performance and / or an improvement in Result in quality. However, the performance of a press is based on the optimal coordination of all Components dependent.

• - Vermeiden des Abkühlens der Späne vor der Beleimung.
• - Minimierung des Energiebedarfes.
• - Erreichen eines höchstmöglichen Ausstoßes einer Strangpresse.
• - Verbesserung der Qualität der Erzeugnisse.
• - Verringerung des Platzbedarfes einer Strangpresse.

The invention therefore has the following objects:

• - Avoid cooling the chips before gluing.
• - minimization of energy requirements.
• - Achieving the highest possible extrusion output.
• - Improve the quality of the products.
• - Reduction of the space requirement of an extrusion press.

The objects of the invention have been achieved with the features of the claims.

The invention achieves its object with the use of a number of previously known ones Teachings, as well as another series of as yet unpublished applications, which later in be called individual. These teachings are optimized and become one device merged.

The production costs for strands influenced by the method and the device Small parts, especially small wooden parts, from the z. B. pallet blocks or door panels cut, essentially consist of the drying costs for the chips, the amount of glue required and its composition, the cost of compaction and the curing costs together. The glue costs are not dealt with here. The The greatest cost is caused by drying the small parts. The previously known Extrusion presses can only process small wooden parts up to a moisture of approx. 2% dry. Though Unlike chipboard presses, there are no steam tensions, but they do Small parts are too soft at a humidity of more than 2% atro, they behave more hydraulic and generate a higher friction on the boundary surfaces of the filling and Press room as well as the mandrel and the preheating channel.

• - der Dorn während des Presshubes in Haftreibung im Strang eingespannt ist,
• - durch/mit den/dem Dorn, bis sich der Strang bewegt keine, oder eine deutlich unter der zum Erreichen der gewünschten Verdichtung liegende Gegenhaltekraft zum Pressstempel erzeugt wird,
• - und diese mit Beginn des Transportes des Stranges in Pressrichtung des Pressstempels bis zum Ende des Presshubes des Pressstempels, auf die zum Erreichen der gewünschten Dichte des Stranges notwendige Höhe verändert wird;
• - beim Presshub, während des Stillstandes des Stranges nur eine teilweise Verdichtung des sich neu bildenden Strangteiles erfolgt und die gewünschte Verdichtung erst etwa bei Ende der Bewegung des Stranges erreicht wird,
• - wobei die gesamte Verdichtung im Bereich unter der Einlauföffnung des Füll- und Pressraumes, zuzüglich dem Überlaufweg des Pressstempels und dem Bereich der Länge des sich neu bildenden Strangteilstückes erfolgt.

With a chip moisture of approx. 8% dry, the drying costs decrease by approx. 30% compared to a moisture of 2% dry. In order to be able to process chips or small wooden parts of this moisture or even higher in piston rod extrusion, the invention teaches the use of a moving mandrel according to. EP 0 339 497, or even more advantageously according to the as yet unpublished application P 102 25 478.8. This process is characterized in that

• - The mandrel is clamped in static friction in the strand during the press stroke,
• - by / with the / the mandrel until the strand does not move or a counter force to the press ram which is well below the required compression to achieve the desired compression is generated,
• - And this with the beginning of the transport of the strand in the pressing direction of the press die until the end of the press stroke of the press die, to which the height necessary to achieve the desired density of the strand is changed;
• during the press stroke, during the standstill of the strand only partial compression of the newly formed strand part takes place and the desired compression is only achieved approximately at the end of the movement of the strand,
• - The entire compression takes place in the area under the inlet opening of the filling and pressing chamber, plus the overflow path of the press ram and the area of the length of the newly formed strand section.

With this teaching, not only are the strand sections compressed at approximately the same height at their ends, but the fact that the small parts are supported not only on the boundary walls of the filling and pressing chamber but also on the moving mandrel during compression, makes the strand much more compact Strength needed. In the case of standing mandrels, as in the case of extrusion tube presses according to DE 29 32 406, a compression force of approximately 50 to approximately 60 kp / cm ^{2 of} strand end face is required in order to achieve a strand density of 0.58 to 0.63 kg / dm ³ . Simply by using the moving mandrel, the compression force drops by 10 to 20 kp / cm ² .

In a simplified version, which is particularly suitable for shorter press ram strokes or for modernizing the existing presses, the invention dispenses with the Dorn cylinder. In this version, the mandrel hangs longitudinally with a flange on the rear End of the plunger tube or the pressure plate. During the press stroke, the mandrel is in its rear position until the strand starts to move and carries its ejection stroke with it out. If the press stamp moves back, the mandrel is pulled back by the ejection stroke. The Mandrel is made so long that the strand does not or during the press ram return stroke is not significantly moved or compressed.

With the as yet unpublished application P 102 25 478.8 the press stamp and the mandrel is guided with linear guides that also absorb the transverse forces. This The design of the press and mandrel cylinder combination is characterized by a shorter design and the fact that heat from the heated mandrel enters the cylinders as much as possible can be avoided.

In a further advantageous embodiment, the invention arranges the mandrel cylinder in one Axis behind the press cylinder. Both cylinders have hollow, continuous Piston tubes, on the opposite ends of which the switching cams or switching plates are attached. The two cylinders are expediently connected by a Spacer tube, which protects the piston tubes and the switching elements, e.g. B. limit switch, Analog initiators, proximity switches or magnetorestrictive position sensors. The advantage this design of a press and mandrel cylinder combination according to the invention is in the Simplicity and the fact that an existing mandrel cylinder is relatively inexpensive can be grown.

One reason for the relatively short service life of the guides, seals and Piston tubes of the existing cylinders are not only in the lateral forces that occur, but in the lack of coaxiality of the individual parts. The invention remedies this evil as follows: You uses commercially available, case hardened and for all piston rods and piston tubes hard chrome-plated pipes or piston rods, for example, it strikes for Pallet block profile of 100 × 145 mm a precision hollow shaft from Bosch-Rexroth-Star with one Outside diameter of 80 mm and an inside diameter of 57.4 mm. The The surface layer of this hollow shaft has a martensitic structure with a hardness of HCR 60 and a tough core structure made of pearlite and ferrite.

In the previously known embodiment, two piston tubes are optionally used different outside diameters, screwed together over the piston. When assembled there is a static overdetermination, which is due to the lack of coaxiality with the leads to the short service life mentioned. However, the invention carries out the piston tube one piece. It turns grooves from the outside into which they are divided, round or Rectangular locking rings prefer the die base, which consists of two parts screwed piston and the switch cam fixed.

In a further preferred embodiment, the piston tube consists of a pressure piston run, and a retracting piston run and also fastens the parts to be attached split circlips. The piston is executed in such a tolerance range and provided with recesses on the inside so that it can move slightly coaxially and one slight angular movement of the two piston tubes is possible. This will make the static Overdetermination eliminated.

In extrusion, i.e. the production of strands without holes, there is no hollow one Piston tube but only a piston rod required, which the invention from behind provided with a blind hole into which a magnetorestrictive position sensor protrudes. As Semi-finished product, the invention uses a commercially available, case-hardened and hard chrome-plated Piston rod. To absorb certain transverse forces despite very high piston speeds To be able to, the invention provides both the piston and the rod bushing additional tours. The guides on the Provide sealing surface with relief grooves. For example, their size can be up to about 3 mm Width and up to approx. 1 mm in depth. Depending on the diameter, the invention proposes 1 up to 3 additional relief grooves.

The transverse forces acting on the piston rod or the ram tube, which are caused by the invention almost completely eliminates inadequate filling, that the press die head plate and, if available, the mandrel bush according to the still unpublished application P 102 33 121.9 can be made radially evasive. For this purpose, the invention produces the press ram base plate with a larger bore than that associated diameter he two-part mandrel bush. This is provided with a nose and is held together by a tube pushed over it and by one Circlip fixed longitudinally. The division of the mandrel bushing in two is an advantage because Mandrel bushing that is subject to wear and tear, can be replaced without removing the mandrel.

The invention achieves a further reduction in the pressing force by a few kp / cm ² by expanding the filling and pressing space according to DE 40 27 583 in steps. The invariable friction force by which the compression is determined in part is calculated from the area (cm ² ) with which the strand is in contact with the boundary walls x the coefficient of friction x the force of the strand against the boundary walls (kp / cm ² ). Due to the high press speed of up to over 2 m / min. the small parts that compact to form the strand do not rest on the boundary walls immediately after each step, but only after a distance of a few cm and generate friction.

The invention achieves a further reduction in the required pressing force by applying hot water or steam to the strand immediately after the filling and pressing chamber. The steam can be applied either according to EP 0 376 175 or according to the as yet unpublished teaching of P 101 53 193.1 or according to the teaching of PCT / EP / 99/01988 (see FIGS . 14 and 16).

The reduction of the pressing force in EP 0 376 175 results from the fact that in the edge zone the strand of water, in particular hot water or steam is introduced, whereby the Small parts of the edge zone lose their strength with a reduction in volume and that Small parts of the core zone can push outwards. In addition to the smooth, higher density Edge zone results in a lower friction force. The first reactor immediately after filling and press room according to PCT / EP / 99/01988 has the same task.

The teaching of P 101 53 193.1 is characterized in that by the reactor, in shape of hot water, pressurized hot water, or steam or hot gas Most of the thermal energy is introduced into the strand, which is the strand either brings it to a temperature that allows the binder to set or gel quickly, or brings the strand to a temperature at which, below, the strand after Leaving the reactor surrounding pressure, the hot water initially condensed in the strand or the condensed steam evaporates again and largely escapes from the strand, a first semi-rigid curing channel section being arranged after the reactor, the radially against one another starting in the pressing direction from the end of its rigid section certain, adjustable force can expand, and this semi-rigid curing channel section a movable hardening channel section follows in which the binder gels or hardens.

The invention achieves a further reduction in friction by providing the heated mandrel heated over its entire length. For those in use The fixed mandrel will be extruded, provided it has a sufficient cross-section, heated by an electrical heating cartridge of about 2 to 3 m in length. In principle, this is also possible with the invention. However, it teaches the preferred use of one Piston drive according to the as yet unpublished application P 102 25 478.8 and developed the moving mandrel according to OS 198 26 408 as follows:

The hollow-drilled mandrel attached to the mandrel cylinder protrudes through press punches, filling and Press room and the first reactor in the setting channel. The thorn only has the task of To heat the strand indirectly, it is heated with a heating medium, preferably hot water a temperature of up to about 220 ° C or pressurized steam of up to about Heated at 220 ° C. The heating medium is at the end of the mandrel through an inner tube in the mandrel redirected and returned. It does not matter whether the flow of the heating medium through the inner tube or through the mandrel bore. Heating the mandrel in its entire length compared to the heating described above with a heating cartridge the advantage that the mandrel can be made considerably longer. According to the invention protrudes length in the ligating channel so that the force including the The static friction with which the strand is stretched on it is not greater than the breakaway force with which the strand is held with its outer walls in the device. So long as that Strand is not or not significantly moved when the mandrel is withdrawn. This will on the one hand achieves a significantly higher heat-through rate, on the other hand forms between the strand and the mandrel a strongly friction-reducing vapor layer, which in turn again allows a longer mandrel.

If the mandrel has the task of heating the strand predominantly or partially by H ₂ O discharge and / or of introducing hardener into it, it is manufactured as long as possible, but only so long that the strand not only does not move, or only insignificantly, when the mandrel is withdrawn, but is not compressed in length. According to the invention, the H ₂ O enters the strand in the form of steam or as evaporating hot water at temperatures of up to approximately 220 ° C. from bores or slots in the mandrel. The bores or slots are made in the mandrel at intervals of approximately 10 to approximately 100 mm. The distance of the front slot or the front bore to the front mandrel end is dimensioned such that no or only a little H ₂ O reaches the mandrel hole of the strand between the strand and the part of the mandrel lying in front of it. Of course, no H ₂ O return through an inner tube is provided here.

The holes for the H ₂ O outlet can have a diameter of up to about 5 mm. In order to prevent batch parts from penetrating into the holes, the invention places grooves, for example, with ball mills on the hole ends. These grooves can be up to a few cm long and at least as wide as the diameter of the holes. Their depth can be up to the radius of the ball end mill. It is very advantageous to arrange the holes and the grooves spirally around the mandrel axis.

Slots with a slot width of 0.2 to about 1 mm are very easy to pass through Wire EDM or make with metal jigsaw blades. Their distance and arrangement can correspond to those of holes. The slots are made so deep that they Reach mandrel bore.

In addition to the reduction in energy requirements and thus the manufacturing costs through Using more humid small parts of up to 8% atro or more improves the invention the energy balance by further developing P 199 62 513. This teaching is through characterized in that the mixture is composed in such a way that this initially not or only insignificantly cures, and that the batch only in the area of An extrusion device is added, which causes a batch hardening or accelerated. The invention makes use of this teaching by putting before the Extrusion mixes the glue in liquid or powder form with the small parts, and only through the hardener the mandrel and / or through the first and / or second reactor. It improves P 199 62 513 however, very crucial in that they glue the small parts with a higher one Temperature processed as usual. It also solves a different task than the P 199 62 513 Asked. Its main task is to avoid that Batch sets before it is processed in the extrusion press. However, the invention has not the task of extending the possible dwell time of the batch, but that of the Use the energy contained in small parts after the dryer to harden. So it cools them Small parts do not, as usual, such that their temperature after the glue mixer is below about 50 ° C and the batch can be processed for a few minutes, but rather leaves it in a higher temperature range, in which it has no or only little Tie off heat. The temperature is kept as high as possible. It can with liquid Glue amount to 60 ° C to about 90 ° C, i.e. up to the temperature at which the glue reaches Compacting in the extrusion press does not dry out. With powdered glue, the Temperature is significantly higher. However, the steam emerging from the chips must be removed in order to avoid condensation on the device walls. in the Temperature range up to approximately 100 ° C is the use of powdered glue Particularly advantageous because the glue powder on the slightly damp surface of the small parts adheres well.

The required energy to 1 kg of chips with a humidity of 10% dry to 1 ° C heat is about 1.65 kJ. If one takes 45 ° C as the former chip entry temperature and as The chip entry temperature according to the invention into the press 90 ° C. results in a saving of 74.25 kJ per kg of chips during setting, as this amount of heat is no longer available to the strand must be fed.

The filling time of the press is one of the essential criteria for the performance of a press Plodder. In principle, devices according to DE 20 10 071 and PCT / EP99 / 00588 use, the line aimed by the invention of considerably more however, they cannot be implemented as 100,000 blocks / 21 h. The invention uses instead enemas according to DE 41 17 659 or better according to the as yet unpublished Teaching of P 102 28 491.1 or very preferably according to the also unpublished Doctrine of P 102 33 121.9.

P 102 28 491.1 is characterized in that:
the small parts forming a cake and matting in an upper, narrower shaft slide into a lower, enlarged shaft, the cake and / or the matting being largely dissolved, and the small parts get into the passage opening during the standstill and the movement of the slide and emerge from this into the filling and pressing chamber and fill it in a single stroke or a double stroke.

P 102 33 121.9 is characterized in that:
the batch from a feed device, e.g. B. a trough chain conveyor or a screw conveyor directly, without a fixed inlet shaft, into the passage opening of a filling element moved transversely to the pressing direction, from which it is in free fall, or in largely free fall, during the movement of the filling element from one to the other End position, falls out of the passage opening and fills the filling and pressing space of the extrusion or extrusion tube press in a single stroke or a double stroke, the filling and pressing space being closed by the filling element in its position in each of the end positions and the press ram in each of the end positions the filling element can perform its working stroke.

If the task is to make the devices as narrow as possible, the invention develops the latter two teachings further in that they are perpendicular to the pressing direction Provides guide rails with 4 cylinder bores. It runs across each guide rail a bore from both sides to the pressing direction, the ends of which do not touch. The Holes serve as cylinder rooms. The beginning of the hole is provided with glands, through which the piston rods protrude into the bores. Two work according to the invention Plunger cylinders on one side in one direction, the other in the opposite. The Oil is preferably applied through a 4/3 way valve, preferably in proportional technology. A filling device according to the invention for an extrusion press for a pallet block profile Dimension 145 × 145 mm only needs a width of approx. 1.15 m, compared to approx. 2.5 m in a filling device according to DE 41 17 659. The filling process takes place in one Single stroke, d. H. in every end position the press ram carries out its working stroke. Just, at for filling particularly unfavorable cross-sections, the invention works with one Double stroke. Of course, the other versions of this teaching can also be used use advantageously.

In accordance with an extrusion press. DE 29 32 406 by steam according to PCT / EP / 00/04852 and / or. PCT / EP / 06872 harden and the condensed steam by temperature To remove from the strand again, i.e. to heat it to over 100 ° C, is up to approx. 0.2 kg of steam / kg of mixture required. So this is a cost-intensive type the curing.

With steam or hot water curing according to PCT / EP / 99/01988 or according to the unpublished applications P 101 53 193.1 and 102 34 835.9 is with one Batch inlet temperature in the extrusion press of 45 ° C and a setting temperature of approx. At 95 ° C, about 0.11 kg of steam are required. However, the batch inlet temperature is Already at 70 ° C a steam amount of only 0.045 kg / kg batch is required.

However, the invention also teaches the use of powdered glue, for example the Kauraminleim 650 from BASF, Ludwigshafen. This glue needs about half the weight of water to the glue powder to process it. Theoretically, this means that all of the steam or the evaporating hot water is absorbed by the glue. In practice, however, it follows that only a small proportion of H ₂ O has to be removed from the strand after the reactor by a vacuum device according to the as yet unpublished application P 102 34 835.9. The application is characterized in that the strand is brought to a temperature in which the H ₂ O contained in it in the region after the application of a partial vacuum of approximately 0.2 ata to approximately 0.8 ata, preferably around 0.5 ata, evaporates and emerges from the strand, the partial vacuum being generated by an injection condenser by adding cold water and the extraction or vacuum space being within the heating angles or heating plates which are sealed off from one another. Due to the small amount of steam required, it is advantageously not necessary to run the vacuum device over the entire length of the setting channel. Rather, a length of approximately 2 to approximately 8 m is sufficient.

The invention teaches the following structure of a setting channel for strands with holes, but without a set outer layer being generated before steam injection for strand heating:
After the filling and pressing room there follows a heating duct according to the as yet unpublished application P 101 53 193.1 combined with a vacuum device according to the as yet unpublished application P 102 34 853.9.

P 101 53 193.1 is characterized in that by the reactor, in the form of hot Water, pressurized hot water, or steam or hot gas predominant part of the heat energy is introduced into the strand, the strand either on a Bring temperature that binds or binds the binder quickly, or the strand to a temperature at which, under which, the strand after leaving the Pressure surrounding the reactor, the hot water initially condensed in the line or the condensed steam evaporates again and largely emerges from the line, after the A first semi-rigid curing channel section is arranged in the reactor Pressing direction radially against a certain, starting from the end of its rigid section adjustable force can expand, and this semi-rigid curing channel section a movable Curing channel section follows, in which the binder gels or hardens.

The mandrel described at the beginning protrudes so far into the tying channel that it is retracted does not move the strand or only insignificantly and does not compress it. Its length continues dimensioned so that the rearmost steam outlet opening as far from the front Steam outlet of the reactor is removed that the outer peripheral zone of the strand again has dried and is sufficiently dimensionally stable, in practice about 1.5 to 8 m. Both through the mandrel as well as through the reactor will only provide a portion of the heat to the strand the setting temperature required steam introduced. This means that the Strand, since the condensed water from the respective outlet openings does not all Strand cross section softens, remains sufficiently longitudinally stable during the ejection stroke and the Glue rest is obtained.

In a further advantageous embodiment, the invention uses a reactor according to EP 0 376 175 after the filling and pressing chamber in order to achieve a particularly smooth, higher-density edge zone and to reduce the friction. The H ₂ O required for strand heating is essentially introduced into the strand through the mandrel. A vacuum device according to P 102 34 835.9 is provided.

Since the strand has only a relatively low diffusion resistance, the invention seals the pinhole as follows. On the back spine, she puts another pole, the protrudes about 0.2 to 2 m above the front end of the vacuum device, or is so long that the end of the sealing plug does not protrude from the heating duct, and in diameter about 0.5 to 5 mm smaller than the mandrel. A sealing plug is attached to the rod. The Sealing stopper is dimensioned in such a way that it fits in a slight sliding fit Strand lies. Adequate tightness is achieved by the length of the stopper. Just like that The tightness can be advantageous by using commercially available piston rings from engine construction shorter sealing stoppers can be achieved. Of course, other sealing devices are also conceivable and advantageous for the stopper.

In a further advantageous embodiment, the invention dispenses with the aforementioned vacuum device and generates the vacuum through the pinhole. The mandrel is designed as mentioned above, but without the slots or holes. Rather, these are introduced in sufficient numbers into the rod mentioned, which is hollow like the mandrel. This version is particularly suitable for the use of powdered glue, since significantly less H ₂ O has to be removed from the strand. Due to the distance between the capacitor, a surface capacitor is particularly advantageous here. Due to the relatively high proportion of inert gas, the invention provides an auxiliary pump.

The invention provides the following advantageous designs of the setting channel for the production of strands without a hole:
If the strand is sufficiently longitudinally stable, in particular if only a little H ₂ O is required for strand heating, such as when using powder glue or the higher batch temperature according to the invention, a setting channel according to P 101 53 193.1 with a vacuum device according to the as yet unpublished application P 102 34 835.9 combined.

If the strand is not sufficiently longitudinally stable, the invention combines the teaching of PCT / EP / 99/01988 with P 102 34 835.9 as follows:
If a particularly smooth, more highly compressed edge zone is to be produced, the filling and pressing chamber is followed by a reactor according to EP 0 376 175, followed by a heating duct with a vacuum device according to P 102 34 835.9.

If no particularly smooth, higher density edge zone is desired or necessary, follow the filling and pressing room a heating duct with a vacuum device acc. P 102 34 835.9. The control of the strand density can either according to DE 25 35 989 at slow, or at higher feed speeds by a height adjustable during the Presshubes variable force of the pressure cylinder (chip elements) of the heating channel. The The strand is only moved for a very short time. E.g. with a press with 700 mm travel, a strand compression of 1: 3.75, a degree of filling of 85% and one Press speed of 1.5 m / s, the strand moves only 0.106 s. The press stroke only lasts 0.46 s. These values are in the presses in operation according to DE 29 32 406 reached. In view of the short times for the strand movement and the punch stroke could not find a reasonably exact change in the force of the tensioning cylinder of the heating duct will be realized. The fact that it was never realized was simply not recognized, despite that It is controlled by small, not quickly switching valves of size NW6. The The invention therefore teaches instead of the previously known single-acting chip elements (Hydraulic cylinder) to use double-acting and the rod side with an adjustable, but to apply pressure that does not change during the press stroke. The feed pipes it leads to the cylinders in a relatively large dimension from z. B. with a Diameter from about 20 to about 35 mm. It also connects to the feed pipe Rod side at least one, but preferably several pressure accumulators distributed over the length on. This is an immediate, almost instantaneous reduction in tension the cylinder reaches because the pressure on the pressure side is preferably via a proportional pressure Valve is set. The strand density is controlled in a "three-pressure system", a low pressure, a medium pressure and a higher pressure. The medium pressure is present during the strand movement, the lower one in the phase of the breakaway of the Stranges from stiction. The low pressure is so low that the medium one that the Breakaway force corresponds approximately to the transport force of the strand. During the rest of the year Press cycle applies the higher force that securely clamps the strand. By pressure on the Rod side, a constant force is also required on the pressure side so that the Do not lift off the movable heating bracket or heating plates or heating trays. At the The pressure proportional valve is therefore constantly under voltage. A change in pressure in a extremely short time of a few ms. The system surprisingly works this way quickly that under certain circumstances on a density control by the mandrel cylinder or this can be dispensed with. However, it is provided in a particularly advantageous manner to combine both types of density control of the strand. The higher pressure becomes like this determines that the strand is securely clamped. The positions in which from the higher up the lower and from this to the medium pressure are switched by the Position of the plunger determined.

The invention has a completely different function than in DE 25 35 98, in which only the Press stroke there is a lower pressure than the return stroke. The invention is a Back pressure, which enables the very fast change of the contact pressure and over the force on the rod side, which is in a lower phase during the breakaway of the strand from static friction, a phase of medium pressure during the strand transport and a phase of higher pressure during the rest period of the Strand. So there is no direct, but only an indirect connection between Press force with the press cylinder function.

In a simpler embodiment, the invention is satisfied with a two-pressure system, which, however, also differs entirely from the function of DE 25 35 989. she uses the structure of the device described above and places one on the rod side constant but adjustable back pressure. The contact force is during the press cycle also constant with the exception of the breakaway phase. In this phase the pressure on the Print area reduced so that the difference between the higher breakaway force of the Stranges to the extension force is balanced.

The invention preferably uses its own small hydraulic system for density control with about 1.1 to about 2.2 kW, a pressure accumulator and one Proportional pressure relief valve.

Instead of the piston presses described, the invention teaches in particular with round or square extruded profiles for pallet blocks the use of continuous presses according to EP 02 000525.2 or P 101 01 386 A1 and / or PCT / EP / 99 / 01987. These teachings can be combined very advantageously with the curing channels described above.

The presses described currently achieve an output of up to about 10 m / min. It is foreseeable that these performances will be further increased if these devices come into use. The previously known, 4-blade saws are not able to to cut so many blocks. The invention therefore uses the cross-cut saws according to P 101 01 823 A1 and / or P 102 16 176.3.

The invention is described below without restricting the general inventive concept based on exemplary embodiments with reference to the drawings described, with the rest of the disclosure of all in the text is not closer explained details of the invention is expressly pointed out.

Show it:

Fig. 1, a longitudinal section through an extruder.

Fig. 2, a cross section through an extruder on the line II of FIG. 1

Fig. 3 shows a side view of a press and mandrel cylinder combination with a mandrel.

Fig. 4, a section through a sealing plug.

Fig. 5, a detail in the circle II-II of FIG. 3.

Fig. 6, a detail in the circle II-II of FIG. 3.

Fig. 7, a cross section through Heizwinkel for rectangular extruded profiles along the lines III-III and IV-IV of FIG. 1.

Fig. 8, a cross section through a sealing profile.

Fig. 9 is a front view of a heating channel on the line VV of FIG. 1.

Fig. 10, a side view of a press and mandrel cylinder combination with a mandrel.

Fig. 11, a section through a press and mandrel cylinder combination with a mandrel.

Fig. 12 shows a section through a press and mandrel cylinder combination with a mandrel.

Fig. 13, a section through a press ram and a mandrel.

Fig. 14, a section through a press ram and a mandrel.

Fig. 15, a section through a press ram and a mandrel.

Fig. 16, a section through a press ram and a mandrel.

Fig. 17, a section through a press ram.

Fig. 18, a section through a piston tube.

Fig. 19, a partial section through a piston tube.

Fig. 20, a detail in the direction of arrow VI.

Fig. 21, a longitudinal section through a press ram.

Fig. 22, a plan view of a press die.

FIG. 23 is a detail section on the line VII-VII in Fig. 22.

FIG. 24 is a detail section in the direction of arrow VIII according to Fig. 20.

Fig. 25, a section through an extruder.

Fig. 26, a section through an extrusion press.

Fig. 27, a section through a continuous extruder.

Fig. 28, a section through a continuous extruder.

Fig. 1 shows a longitudinal section through an extrusion press with which an angular pallet block profile is produced. In the exemplary embodiment, the strand is brought to the setting temperature by the reactor 1 and by the mandrel 2 . The batch fed to the metering slide 4 with the cross conveyor 3 is glued without hardener. The hardener is first fed through the reactor 1 and the mandrel 2 with the steam or the hot water that heats the strand. As a result, the batch temperature can be about 50 ° C to more than about 90 ° C. The amount of energy required and therefore the H ₂ O requirement to achieve rapid setting is correspondingly lower. The setting channel 5 following the reactor no longer has the task of heating the strand entirely, but merely has to temper it and guide it during the setting in such a way that the glue rest is ensured. Its internal structure corresponds to P 101 53 193.1, but is improved compared to this invention in that the partial vacuum created in the line is generated according to P 102 34 835.9 within heating angles 6 , 7 , 8 and 9 . The tensioning elements 10 press the heating angles 5 and 7 against the strand with constant force during the extension stroke. Only in the case of particularly sensitive strands does the invention provide a variable force of the tensioning elements 10 according to DE 25 35 989. The length of the setting channel 5 is dimensioned according to the setting time of the binder and the output of the extrusion press.

example

Setting time 1 min. Discharge speed 8 m / min. Minimum length of the heating duct = 8 m. The The invention here proposes a length of 12 or 15 m in order to provide a sufficient reserve have. If a tannin glue is used as glue instead of the usual melamine glue, a a correspondingly longer setting channel should be provided, since the setting time of tannin glues about 1.5 to about 3.5 minutes.

The mandrel 2 is shown in more detail in FIGS. 3, 4 and 5. Its length in dimension 11 is approximately 1.5 to 8 m and is dimensioned such that the outer surface of the strand has already dried again and has thus become longitudinally stable before the strand is heated in its inner region by the steam or hot water emerging from the mandrel slots , This advantageous division of the steam or hot water supply results in the longitudinal stability of the strand. With the length of the mandrel, however, it must be ensured that the strand is not or not significantly moved back or compressed when the mandrel is withdrawn.

The filling and pressing room is manufactured in a known manner. The metering slide 4 is a further development of the as yet unpublished application P 102 33 121.9. In order to keep the press width as small as possible, the plunger cylinders 12 are integrated into the guides 13 . In practice, a press width of approx. 1.15 to 1.25 m can be realized with a pallet block profile of 145 mm in width. The plunger cylinders 12 are advantageously controlled by a 4/3 way valve, preferably using proportional technology.

As a drive for the press ram 14 , the invention particularly preferably uses a press and mandrel cylinder combination 15 according to P 102 25 478.8 when extruding tubes. With this teaching, an at least approximately equal density of the strand parts produced with each stroke is achieved at their ends. The press ram is mounted on the press rod 16 so as to be radially movable. This is shown in more detail in FIGS. 21 to 24. Instead of P 102 25 478.8, the other press and mandrel cylinders described below can also be used in an advantageous manner.

FIG. 2 shows a cross section through an extrusion press on line II according to FIG. 1. The exemplary embodiment treats a metering slide 17 with two metering chambers 18 and 19 . Of course, instead of the selected version, other versions of metering slides, as described in P 102 33 121.9 or P 102 28 391.1, can also be implemented with advantage with plunger cylinders 21 integrated in the guides 20 . Since the metering slide 17 has some 1/10 mm play in its guides, the piston rods 22 are mounted in the cross members 23 so as to be radially movable. In addition to the advantage of the compact width of the press with integrated plunger cylinders, another advantage of this design is that the piston rods 22 and the seals in the stuffing boxes 24 can be exchanged very easily.

Fig. 3 shows a side view of a press and mandrel cylinder combination 25 according to P 102 25 478.8 with a mandrel 26 for the H ₂ O entry into the strand. The length in dimension 27 is dimensioned such that there is a distance of approximately 1.5 to approximately 8 m in dimension 11 of FIG. 1. The dimension relates to the distance from the front H ₂ O exit edge of the reactor of FIG. 1 and the rear H ₂ O trailing edge 28 . It is essential when determining the length in dimension 27 that the strand is not moved or is moved only insignificantly and is never compressed when the mandrel 26 is withdrawn. If the mandrel friction is too large due to the required mandrel length in the dimension 27 , the invention teaches that the mandrel 26 in the area behind the rear H ₂ O trailing edge 28 has a sufficient length slightly in diameter, e.g. B. down to about 0.5 mm. The distance in dimension 29 is dimensioned such that no or hardly any H ₂ O reaches the area of the rod or mandrel taper 30 instead of in the strand. The length of the mandrel taper in size 31 corresponds approximately to the length of the vacuum device in the heating duct, but is continued in the direction of the press if necessary, if this requires mandrel friction. The mandrel taper in size 31 can be approx. 0.25 to approx. 5 mm and depends on the mandrel diameter. At the thorn rejuvenate the sealing plug 32 connects. Its length in dimension 33 is dimensioned such that no or only a little external air is sucked in from the mandrel through the vacuum device.

Fig. 4 shows a section through a sealing plug. In the exemplary embodiment, the sealing plug 34 is held in dimension 35 in a tolerance of approximately 0.1 to approximately 1 mm to the mandrel hole. The seal against the pin hole is provided by the sealing rings 36 , preferably commercially available piston seals from engine construction. The length of the sealing plug in dimension 37 can be kept significantly smaller in the exemplary embodiment than in the embodiment of FIG. 3, for example, it can be up to 5 times the mandrel diameter. The mandrel taper in size 38 can also be up to about 5 mm, depending on the mandrel diameter. The surface 39 is chamfered according to the invention, so that small parts or dust particles dropped from the pinhole do not cause blockage. Up to about 5 sealing rings 36 have proven successful.

FIG. 5 shows a detail in the circle II-II according to FIG. 3. The steam outlet openings 40 are made as narrow slots in the exemplary embodiment. Their width in dimension 41 can be up to approximately 1 mm, but preferably around 0.3 mm. They can be sawn by wire EDM or in a surprisingly simple and inexpensive way with a jigsaw with metal blades. For example, a slot in a mandrel tube with an outside diameter of 42 mm and an inside diameter of 20 mm can be sawed by hand within a few minutes. In the exemplary embodiment, 4 slots are made distributed over the circumference. The number of slots depends, however, on the amount of H ₂ O to be discharged. It may well be that more than 12 slots are required if, in a particularly advantageous embodiment of the invention, a reactor according to EP 0 376 175 only has a more compact and particularly smooth one Surface layer is generated in the strand and the strand heating takes place essentially from the inside through the mandrel. The spacing of the slots from one another can be up to about 100 mm in dimension 42 , the total length of the H ₂ O outlet zone in dimension 43 being at least about 1 to about 4 times the length of the strand piece produced with each pressing cycle. In the case of continuous presses, a value of approx. 50 to approx. 500 mm can be given for dimension 43 . However, this is largely dependent on the feed speed of the press and whether the strand heating is carried out from the outside and inside or predominantly or exclusively from the mandrel.

FIG. 6 shows a detail in the circle II-II according to FIG. 3. In the exemplary embodiment, the H ₂ O discharge from the mandrel takes place through the holes 44 distributed over the circumference, the diameter of which is up to approximately 5 mm. The number of holes 44 depends on the amount of H ₂ O to be discharged and on their diameter, as does the distance between the holes 44 in the pressing direction. So that the holes 44 are not blocked by small parts or dust particles, the invention provides the recesses 45 produced with a ball mill. Their depth in dimension 46 can be up to the radius of the ball end mill. The length in dimension 47 can be up to several cm and the width in dimension 48 from one to about two times the hole diameter.

FIG. 7 shows a cross section through heating angles for angular extruded profiles on the lines III-III and IV-IV according to FIG. 1. The rigid heating angle 49 and the movable heating angle 50 are worked out in cross-section approximately identically from one piece. Contrary to the first impression, working out the contour from an annealed steel block is considerably cheaper than screwing two legs together. The groove 51 for the seals 52 is worked into both heating angles. In the rigid heating bracket 49 , the two trigger grooves 53 are milled, which protrude almost to the end of the bracket. The invention dispenses with angular strands with chamfered edges on the trigger grooves when no condensation occurs and the chamfer 54 is sufficiently large, for. B. 15 × 15 mm. The H ₂ O and the foreign substances emerging from the strand are most easily fed to the capacitor via lines which end in the screw connections 55 . The necessary thermal energy is supplied to the heating angles by heat transfer oil or hot water via the bores 56 in the usual way. The corners 57 of the heating angle can be rounded instead of sharp-edged, as shown, or executed according to the strand 58 .

Fig. 8 shows a cross section through a sealing profile 59th It is shown in the assembled state under number 52 in FIG. 7. Its width and height depend on the heating angles. As a guideline for the width in dimension 60 , 3 to about 15 mm and for the height in dimension 61 from 4 to 20 mm can be mentioned. The upper surface is toothed, and the teeth can have an angle in the dimension 62 of approximately 15 ° to approximately 90 ° and a depth in the dimension 63 to approximately 4 mm. A preferred embodiment has a height in the dimension 61 of approximately 15 mm, a width in the dimension 60 of 9 mm, a tooth angle in the dimension 62 of 35 ° and a tooth height in the dimension 63 of 2.5 mm. The seal 59 is extruded and cut to length as required. It is made of heat-resistant plastic such. B. PEEK (polyether ether ketone; Virtex®) or FPM (fluororubber; Viton®) or manufactured. A suitable hardness can be given as 55 to 90 Shore. Of course, other advantageous shapes and designs for the seal can also be selected.

FIG. 9 shows a front view of a heating duct on the line VV according to FIG. 1. The illustration is schematic, the exemplary embodiment corresponds to the as yet unpublished application P 102 34 835.9. The movable heating bracket 64 is fastened radially displaceably on the folding bracket 65 and is pressed by the force transducer 66 in a known manner against the rigid heating bracket 67 . The heating duct is secured by screws 68 and can be opened about axis 69 . In order that no or only a small amount of force is required for this purpose, the invention compensates for the weight of the pivotable debris by means of gas tension springs 70 . The throttle cable springs are an extremely inexpensive and space-saving alternative to counterweights or hydraulic solutions. The gases emerging from the branch 71 and the H ₂ O reach the injection condenser 73 via the lines 72 . In its condensation space 74 , preferably at the level of the lines 72 , finely atomized, cold water 76 is injected from the tube 75 , which allows the H ₂ O to condense. In the event that too much external air is supplied or there is too much inert gas, the vacuum is increased by an additional pump. The condensation is started either by this additional pump or an auxiliary pump, or by slowly starting the press, which heats the strand to over 100 ° C and H ₂ O escapes as steam, which condenses in the condenser and the partial vacuum generated. Then the performance of the press is increased. The vacuum can increase between about 0.2 to about 0.8 ata, press. The vacuum can be between about 0.2 to about 0.8 ata, preferably around 0.5 ata. This means that the system can tolerate a certain amount of external air or inert gas. The strand is only exposed to the partial vacuum to the required length. This means that the vacuum device does not have to extend over the entire length of the heating duct. Instead of the gas tension spring 70 , a gas pressure spring pushing in the opposite direction can also be used.

Fig. 10 shows a side view of a press and mandrel cylinder combination with a mandrel without heating, or an electrical resistance heater. As a drive for the press die 77 and the mandrel 78 , the exemplary embodiment selects a press and mandrel cylinder combination in accordance with the as yet unpublished application P 102 25 478.8. The rear mandrel run 79 is made so long in dimension 80 that the static friction on the strand, including the static friction through the sealing plug 81, is as large as possible, but is so small that the strand is not or only slightly moved or even compressed when the mandrel 78 is withdrawn , If the heating duct has a vacuum device, a thinner mandrel center piece 82 is provided, which in diameter can correspond approximately to the values mentioned in FIG. 4. The rear edge 83 of the sealing plug lies in the pressing direction at the level or somewhat in front of the end of the vacuum device. If the vacuum device reaches the end of the heating duct, the sealing plug ends approximately with the heating duct. Has the mandrel 78 a sufficient diameter, for. B. from about 16 mm, an electrical resistance heater can be installed in the rear Dorntrumm 79 . Resistance heaters of this type are commercially available from a diameter of approximately 6.5 mm up to a length of approximately 3 m or can be obtained as special dimensions. Their heating output is around 1 to around 3.5 kW. This energy appears low. In practice, however, it was found that with a strand cross-section of 100 × 145 mm and a heating power of the mandrel of 2.5 kW, the heating time is reduced by approximately 20%. The sealing plug is shown in FIGS. 3 and 4.

Fig. 11 shows a section through a press and mandrel cylinder combination with a mandrel. In the exemplary embodiment, the mandrel 84 is mounted in the mandrel cylinder 85 and the press die 86 is fastened on the piston tube 87 of the press cylinder 88 . The press cylinder 88 and the mandrel cylinder 85 are mounted coaxially one behind the other via the switch tube 89 such that the switch cams 90 and 91 do not touch even when the press piston rod is in its rear end position and the mandrel piston tube 92 is in its front end position. The cross section of the mandrel cylinder 85 is approximately the same as that of the press cylinder 89 . A switch tube 94 is attached to its rear end 93 to protect the mandrel piston tube 92 . The structure of the mandrel corresponds to that of FIG. 10 or that of FIG. 3. If a mandrel according to FIG. 3 is used, however, the invention teaches that the inner contours 95 and 96 of the piston tubes 87 and 92 are covered inwards with a heat-insulating material , so that not too much heat penetrates into the cylinders and heats the hydraulic oil unnecessarily or inadmissibly. In the exemplary embodiment, the end positions of the press cylinder 88 and the mandrel cylinder 85 are queried via the truncated cone-shaped switching cams 90 and 91 and the analog initiators 97 and the valves are controlled accordingly. If the cylinders are advantageously actuated with proportional valves, the analog initiators 97 are used. If conventional 4/3 valves are used, the invention teaches the use of limit switches or proximity switches instead of the analog initiators 97 . The press and mandrel cylinder combination shown in the exemplary embodiment builds considerably longer than the press and mandrel cylinder combination in accordance with P 102 25 478.8, but is somewhat easier and cheaper to manufacture. It can also absorb only low lateral forces. It is therefore particularly important to fill the filling and pressing space of the press as completely as possible and to store the pressing die 86 so that it can be axially deflected.

The designer of an extrusion press has to decide in a specific application which type of press and mandrel cylinder combination is the more advantageous.

Fig. 12 shows a section through a press and mandrel cylinder combination with a mandrel. In the exemplary embodiment, the position of the press piston tube 98 and the mandrel piston tube 99 is not sensed by analog initiators, but advantageously by means of magnetorestrictive position sensors 100 , for example the R series from MTS Sensor-Technologie in D-58513 Lüdenscheid. Although these sensors are somewhat more expensive than analog initiators, they cannot be adjusted manually by poorly trained system operators. In the past, this "screwing" of the analog initiators has repeatedly caused the presses to malfunction and necessitated readjustment by experts.

Fig. 13 shows a section through a press die and a mandrel. The application example deals with a particularly simple design of the drive for the press ram 101 with a less long stroke of up to approximately 800 mm, which can, however, be longer with larger strand cross sections. In the previous figures, press and mandrel cylinder combinations were described, in which the mandrel cylinder controls the strand density and the strand acts as a counterpressing punch, which results in the largely identical density of the strand dividing ends. With shorter press ram strokes, this function can be dispensed with, assuming a slightly lower quality than the best possible. This is particularly true and even advantageous if the previous quality is improved. It is particularly advantageous that the existing press cylinders can be converted at the lowest cost. It is only necessary to remove the end piece of the existing switching tube, so that an open switching tube 102 is created. The invention further provides for the press ram to be designed to be radially evasive, as described in FIGS. 21 to 24. The position of the plunger tube 103 can be queried by means of analog initiators 104 or via limit switches or proximity switches of magnetorestrictive position sensors 105 . The embodiment is particularly suitable for unheated or electrically heated mandrels. For mandrels with an H ₂ O bushing, the inner wall 106 of the plunger tube 103 must be lined with heat insulation. The mandrel 107 corresponds to one of the aforementioned designs.

The drawing shows the press ram 101 and the mandrel 107 in its rear end position.

FIG. 14 shows a section through a press ram and a mandrel as described under FIG. 13. In the illustration, the stamp 108 has traveled about half of its way. That the strand has not yet moved in this position, the mandrel 109 is still in its rear position.

FIG. 15 shows a section through a press ram and a mandrel, as described in FIGS. 13 and 14. In the illustration, the press ram 110 has reached its forward position and moved the strand forward by the ejection stroke. The mandrel 112 was dragged forward by about the same distance in dimension 111 . The rear mandrel run 113 is made so long in dimension 114 that the static friction on the strand, including the static friction through the sealing plug 115, is as large as possible, but is so low that the strand is not or only slightly moved or even compressed when the mandrel 112 is withdrawn , The middle mandrel strand 116 , if the binding channel has a vacuum device, is manufactured in the aforementioned manner, as is the sealing plug 115 . If no vacuum device is provided, the middle mandrel strand 116 and the sealing plug 115 are omitted.

The mandrel 112 , which runs virtually without resistance, brings considerable advantages over the previously known fixed mandrels in extrusion molding. With fixed mandrels, the friction is unnecessarily increased and the controllability of the press is reduced accordingly. The freely moving mandrel significantly reduces friction. In practice, the pressing force acts better on the strand, which means that a pressing force which is about 10 to about 20 kp / cm ² lower is required on the end face of the strand.

During the return stroke of the press die 110 , the mandrel 112 is withdrawn by the ejection stroke in the dimension 111 .

Fig. 16 shows a section through a press die and a mandrel. In the exemplary embodiment, the radial guidance is carried out by the commercially available linear guidance 117 , consisting of the guide carriage 118 , the guide rod 119 and the pressure plate 120 . The press punch tube 121 is preferably made from a commercially available square, round or rectangular tube, and the press punch 122 is fastened in a radially evasive manner. The press cylinder 123 is preferably rectangular in the outer profile 124 . The connection between the valve 125 and the pressure chambers of the cylinder 123 can thus be established through bores which, in contrast to pipelines, are more reliable. The position of the press ram is queried by the magnetorestrictive position sensor 126 . The exemplary embodiment is suitable both for unheated, electrically heated mandrels and, in contrast to the exemplary embodiments in FIGS. 11 to 15, particularly for H ₂ O through which mandrels flow, since the press cylinder tube 127 is not or hardly heated. If necessary, the invention provides thermal insulation 128 . The mandrel 129 is mounted in the pressure plate 120 and the plunger 122 so as to be longitudinally movable. He is described as in Fig. 15, pulled from the train to the exhaust stroke and withdrawn from the press cylinder 123 by the same distance.

Fig. 17 shows a section through a press die for extrusion molding, so the pressing of strands without a hole. In principle, commercially available double-acting hydraulic cylinders can be used. However, the invention advises the use of specially designed cylinders in order to achieve both a high press performance and a long service life. A short overall length is also sought. The invention therefore supports the ram 130 in a radially movable manner on the piston rod 131 . The stuffing box 132 and the piston 133 are provided with seals 134 and guides 135 , which rule out metallic contact and prevent the build-up of drag pressures. The invention preferably uses elements from the Hunger DFE company in Würzburg, but modifies the guides by means of relief grooves in the management levels. It is sufficient, for example, if one or four longitudinal grooves of a width of up to about 3 mm and a depth of up to about 1 mm are sawn or filed into the guides of the types FI 136 and FA 137 in order to reliably prevent the build-up of drag pressures. The invention achieves a particularly short version by using magnetorestrictive position sensors 138 . In the embodiment, the cylinder is supplied with hydraulic oil through pipes, not shown.

Fig. 18 shows a section through a piston tube. The embodiment deals with press and mandrel cylinders with a continuous piston tube. Since it is not possible to achieve a homogeneous, complete filling of the filling and pressing space and also a radially evacuable press ram generates residual lateral forces, lateral forces act on both the piston rod and the guides, which limit their service life. The piston tubes in use only have a lifespan of 3 to 6 months. Modern high-performance presses would have a correspondingly shorter service life with up to 5 times the output. The known piston tubes are made of the piston, a thicker front tube and a thinner rear tube. The overall structure of the cylinders used results in a lack of coaxiality due to the many parts that are screwed together and manufactured in multiple clamping, which places additional stress on the guides and the piston tubes and leads to the unsatisfactory service life of the parts. At the high piston speeds, surface hardening of the piston tubes is necessary. Although the piston can be made in one piece, case hardened, ground, chrome-plated and polished, such a construction has the disadvantage that a case-hardening steel has to be used which is not available as a tube. The inner hole must therefore be deep-drilled. The production of such a piston tube is therefore not only expensive but, above all, lengthy. Several piston tubes must always be kept in stock in order to have a replacement in the event of damage.

The invention therefore manufactures the piston tube 139 from a commercially available, case-hardened and hard chrome-plated tube, for example it uses a precision hollow shaft from Bosch-Rexroth-Star with an outer diameter of 80 mm and an inner diameter of 57 for a pallet block profile of 100 × 145 mm. 4 mm. The surface layer of these shafts has a martensitic structure with a hardness of HCR 60 and a tough core structure made of pearlite and ferrite. The grooves 140 , 141 and 142 are inserted into the hollow shaft 139 , in which split support rings 143 , 144 and 145 are inserted. They secure the piston 146 screwed together and the die base plate 147, which consists of two parts. The press die head 148 , which is preferably fastened axially movably on the press die base plate 147 , can consist of one part or can be divided into two.

The switching cam 149 can also be divided into two and, like the press ram base plate 147 , is screwed together with screws 150 .

Fig. 19 shows a partial section through a piston tube. While the continuous piston rod of FIG. 18 is still statically overdetermined in spite of the better coaxiality compared to known designs, this is avoided by the divided design of the exemplary embodiment. It also follows that the piston tube 151 of the pressure side 152 has a smaller diameter than the piston tube 153 of the retraction side 154 , which means a lower oil requirement or a higher piston speed. For a pallet block of size 145 × 145 mm, the invention proposes the following diameter: diameter of the piston tube 151 of the pressure side 152 = 80 mm; Diameter of the piston tube 153 of the retreat side 154 = 100 mm; Diameter of the cylinder tube in the dimension 155 = 125 mm. This gives a print area of 72.42 cm ² and a retreat area of 44.16 cm ² . The area ratio is 1: 1.64. A delivery rate of approx. 700 l / min is required to allow the press cylinder to carry out the working stroke of within 1.1 s. The return oil quantity is approx. 1150 l / min. These quantities of oil can be handled by a commercially available proportional 4/3 directional valve of size NW32 without the valve differential pressure being too great. To connect the piston tubes 151 and 153 , the invention places split support rings 156 in the grooves 157 and places a spacer tube 158 between the support rings. The construction is screwed together with the piston 159 and the piston nut 160 . In order to avoid static overdetermination, the invention uses suitable fits and provides the piston bore 161 with a recess 162 , which can have a favorable size of about 0.2 to about 1 mm in dimension 163 . The additional guides 166 achieve a sufficiently stable piston guide. In the exemplary embodiment, guides and seals from Hunger DFE in Würzburg of the types GD 100K and FA were used. They are particularly suitable because they have a considerable distance from metal contact in dimension 164 . Of course, other guides can also be used advantageously. The inner sealing is done by the O-rings 165 and 166 .

Fig. 20 shows a detail in the direction of arrow VI. Since the speed of press and mandrel cylinders according to the invention can go in the direction of 3 m / s, the invention introduces relief grooves 167 into the guides 168 . This reliably prevents the build-up of impermissibly high drag pressures that can destroy the guides and seals. Depending on the speed and diameter, the invention proposes 1 to 5 additional relief grooves, distributed over the circumference, which can have a depth of up to approximately 1 mm in dimension 169 and a width of up to approximately 4 mm in dimension 170 . The grooves can be made in a simple manner by filing.

Fig. 21 shows a longitudinal section through a press die. The die body 171 is divided in two, screwed together and fastened on the press cylinder tube 173 via the two-part support ring 172 . The two mandrel shells 174 are mounted in a radially movable manner in the press cylinder base body 171 . They are guided centrally through the bush 175 and axially through the collar 176 and the locking ring 177 . The end faces 178 and the countersink 179 are conical so that the compressed mixture that has penetrated into the space 180 can be displaced. In order to facilitate migration of the batch being compressed, the press ram profile plate 181 is provided on the strand side with a type of tooth profile perpendicular to the press axis, which is explained in more detail in FIG. 21. After unscrewing the press die profile plate 182 and the press die base body 111 , the mandrel shells 174 can be pulled out and easily replaced without the press having to be emptied and the mandrel having to be pulled out.

Fig. 22 shows a plan view of a press die. The two mandrel shells 183 are positioned centrally around the mandrel 184 . The press stamp profile plate 185 fastened them with the screws 186 and the spacer tubes 187 . The mandrel 184 and the press ram profile plate 185 are thus radially movable independently of one another. A radial mobility of up to approx. 3 mm is sufficient, depending on the size of the extruded profile.

FIG. 23 shows a detail section on the line VII-VII according to FIG. 22. The press ram profile plate 186 is fastened to the press ram base body 189 via the spacer tubes 187 with the screws 188 . Due to the length of the spacer tubes, the press die profile plate 186 can move radially by the dimension 190 of up to approximately 3 mm. The face 192 of the spacer tubes is chamfered so that batches that have penetrated into space 191 can be easily displaced.

FIG. 24 shows a detail section in the direction of arrow VIII according to FIG. 20. The press die profile plate 193 is provided with a tooth profile 194 on the strand side. A particularly simple manufacturing design of the tooth profile is achieved if gear milling cutters with a module of 1.5 to about 6 are used for milling. Of course, the profile can also be made with other tools of approximately the same size. In order that no small parts get caught in the tooth base 195 , the corners 196 are preferably rounded. The embodiments of Fig. 21 to Fig. 24 in accordance with the still unpublished application P 102 33 121.9.

Fig. 25 shows a cross section through an extrusion press for the production of pallet blocks, for example, without a hole. As a filling and pressing chamber 197, the embodiment of FIG. 1 and FIG. Used 2. Of course, other filling and pressing rooms can also be used; in the case of modernizations, the filling and pressing rooms according to DE 29 32 406 may even be retained. As a press cylinder 198, the embodiment of FIG. 17 is used. The length of the press stroke is 199 to about 800 mm. In the case of a recipient according to DE 40 23 583, cross-sections of 100 × 145 mm and 145 × 145 mm can even achieve press strokes of up to approximately 1000 mm. The invention provides for a pressing speed of up to approximately 2 m / s. At a stamping speed of about 1.6 m / s, controlling the strand density by means of single-acting tensioning elements according to DE 25 35 989, as are still used in the extrusion presses in operation, is no longer usable due to the inaccuracy and slowness. Although De 25 35 989 has disc springs installed as retraction elements, the number of these can be adjusted with the required accuracy, which results in undetermined chip conditions. In practice, the telescopic springs are set to "de-energized" and only have the function of preventing the heating angle from tilting when the heating angle is opened.

The invention here chooses a three-pressure system. Here, a higher pressure acts when the strand is not moving, a medium pressure when the strand is in motion and a lower pressure immediately before the strand starts to move until it has overcome the static friction (breakaway phase). This system realizes the invention as follows: It uses double-acting cylinders 200 instead of the single-acting cylinders according to DE 25 35 989. An adjustable pressure, which does not change during the pressing cycle, is applied to the rod side 201 thereof. This pressure has a "relieving effect". So that the relief of the movable heating angle 202 can occur suddenly or very quickly, the feed pipe 203 is carried out in a larger dimension, for. B. a hydraulic tube with diameters of about 20 mm to 35 mm. The dimensions of the connecting pipes or lines 204 can be approximately 6 mm to 10 mm. Since the strand travels its ejection stroke with a press stroke of approx. 1000 mm, a speed of 1.6 m / s and a compression of 1: 3.75 in approximately 0.165 s, one or preferably more pressure accumulators 205 are connected to the feed pipe 203 to further accelerate the relaxation. The pressure is preferably controlled by a proportional valve. The pressure side 206 is supplied via lines or hoses 207 via a likewise larger feed pipe 208 by a proportional pressure control valve. Since there is always pressure on the rod side, pressure is also constantly required on the pressure side 206 . The proportional valve is almost constantly under voltage, it does not need to switch on or off, but only regulates the pressure by changing the voltage, which can happen within a few ms. The pressure change or line density control is carried out as follows:
The higher pressure is present when the plunger 209 is not in the press stroke between the position 210 and the front position 211 . The position 210 is determinable and is set in such a way that it is approximately at a distance from the position 212 in which the strand starts to move, which the press ram travels in the time in which the pressure from the higher setting in the lower one arrives.

When the press ram has reached position 210 , the pressure proportional valve regulates to the low pressure and, after an adjustable time from 2 to about 20 ms, to the medium pressure. The higher pressure is determined such that the strand is securely clamped in the heating duct 213 . The mean pressure in such a way that it produces the desired strand density. The lower pressure is lower by the corresponding value by which the breakaway force of the strand is greater than the transport force. With the system according to the invention, not only is the strand density precisely determined, but also the static friction is compensated. It is therefore a completely different function than in DE 25 35 98, in which only a higher pressure is present during the press stroke than during the return stroke. In the invention, there is a back pressure, which enables the very rapid change of the contact pressure and the contact pressure forces lying above the opposing force, which are in a low phase during the breakaway of the strand from static friction, a medium one during strand transport and a higher one during the rest period of the strand. So there is no direct, but only an indirect connection of the contact pressure with the press cylinder function.

In a simpler embodiment, the invention is satisfied with a two-pressure system, which, however, also differs entirely from the function of DE 25 35 989. she uses the structure of the device described above and places one on the rod side constant but adjustable back pressure. The contact force is during the press cycle also constant with the exception of the breakaway phase. In this phase the pressure on the Print area reduced so that the difference between the higher breakaway force of the Stranges to the extension force is balanced.

In the same advantageous manner, it is possible to control the contact pressure by the rod side 201 of the double-acting cylinders 200 and to keep the pressure on the pressure side 206 constant but adjustable.

With the systems described, precise control of the strand density is achieved, what with the teaching of DE 25 35 98 is not possible or only very inadequately.

The further construction of the heating duct corresponds to that in the exemplary embodiment unpublished application P 102 34 835.9.

In the exemplary embodiment, chips with glue and hardness are processed into strands at a customary temperature, and chips with glue without hardener, the input temperature of which is up to about 90 ° C. in the filling and pressing chamber. In both cases, the strand heating takes place essentially through H ₂ O, which is introduced into the strand by means of the reactor 214 in the manner already described. The strand is exposed in the heating duct 213 to the partial vacuum of approximately 0.2 to approximately 0.8 ata, also described above, preferably by 0.5 ata, as a result of which the H ₂ O condensed therein evaporates, since the strand temperature is higher than that Evaporation temperature of the H ₂ O under partial vacuum. The partial vacuum can be applied over the entire length of the heating channel 213 , or just as advantageously only over a part, if the extensive degassing succeeds in this run.

Fig. 26 shows a cross section through an extruder. In the exemplary embodiment, a filling and pressing space 215 according to FIGS. 1 and 2 is used. If only extrusion is to be carried out on the device, i.e. strands are to be produced without holes, the invention uses the cylinders as shown in FIG. 17 as the press cylinder, for example. Fig. 16, Fig. 3, Fig. 10, Fig. 11, Fig. 12 or Fig. 13 to Fig. 15. The structure of the binding channel 216 is a further developed combination of the as yet unpublished application P 102 34 835.9 and P 102 53 195.8. H ₂ O is introduced into the strand in the form of steam or in the form of hot water or evaporating hot water through the reactor 217 . As described in the introduction, the hardener can be added to the H ₂ O. Without a hardener, the reactor is used to reduce friction and to achieve a smooth, more compact surface. Here, however, the invention provides for the amount of H ₂ O to be increased such that part of the energy for strand heating is already introduced into the strand with this reactor 217 . It has turned out to be advantageous if approximately 5 to approximately 35% of the strand volume is brought to the curing temperature. The strand is conventionally heated at a distance of 218 from approximately 1.5 m to approximately 8 m. This dries the surface or the warmed part of the strand and sets. It is advantageous that the larger amount of H ₂ O allows the distance of 218 in comparison to PCT / EP / 99/01988 to be kept up to about 50% smaller. The second reactor 219 then completely heats the strand to the desired temperature by introducing H ₂ O in the form of steam or hot water or evaporating hot water. The length of the second reactor is 220 at least slightly more than the extrusion stroke of the extruder up to about 4 times. In the case of continuous presses, the length in dimension 220 is kept as short as possible. It depends on the ejection speed of the press and the amount of H ₂ O that can be transported through the reactor in one time unit or is available.

If the binding channel run 221, in which the second reactor 219 is integrated, is produced in a customary length of 3 m and the second reactor is 600 mm long, the length 222 results in a length of 1200 mm. The strand part walls 223 in this area act as a kind of sealing surface, so that little or no H ₂ O emerges from the gaps 224 . The heating angles 225 and 226 are sealed by seals, for example according to FIG. 8. The known partial vacuum, which can act over its entire length or a part thereof, is applied to the other setting channel debris 227 and 228 .

In contrast to DE 101 53 195.8, the invention provides, in addition to the described clamping elements 229, additional clamping elements 230 in order to prevent the heating angles 225 and 226 from moving apart during the H ₂ O entry due to the steam pressure which arises until condensation occurs. The tensioning elements 230 therefore by no means have the task of "reshaping" or re-compacting the strand, as mentioned in PCT / EP00 / 04852, or the claim 2, as mentioned in PCT / EP0006872, "that the sealing of the strand surface ( 17 ) against steam escape through radially compressing deformation of a strand section in the area of the steam supply. " Deformation or recompaction would only destroy the set glue layer. The invention, on the other hand, teaches that the H ₂ O should be introduced continuously into the strand, but in varying amounts / time units. While the strand is being moved, the quantity valve which regulates the amount of H ₂ O is closed to such an extent that only about 10 to about 40% of the amount of H ₂ O / time unit of the remaining time are introduced into the strand. In addition, however, the invention provides for an intermittent introduction of the H ₂ O if the press cycle takes too long because either the press is not powerful enough or a break is inserted between the press cycles for other reasons. Basically, however, it is advantageous that, according to the invention, H ₂ O is also introduced during the press stroke, since a friction-reducing vapor layer then arises between the strand and the heating angles 225 and 226 . The force of the additional tensioning elements 230 is set in such a way that there is no or only slight additional friction of the strand.

At the ends 231 of the binding channel run 221 , the invention provides foldable sealing brackets 232 which prevent H ₂ O leakage to the outside. Sealing can be done, for example, by seals 233 according to FIG. 8.

At the connection points 234 between individual strand part debris, the invention also provides hinged sealing clips 235 which prevent the penetration of too much external air, which would reduce the vacuum in the vacuum area. Sealing can be done, for example, by seals 233 according to FIG. 8.

Fig. 27 shows a section through a continuous extrusion press. The continuous press 23 according to P 101 01 386 is equipped with a press room 237 according to PCT / EP99 / 01982. The compression of the strand is determined by the friction. The result is a reaction force adequate for the compression, which the compression element 238 wants to push against the pressing direction. The deeper the compression element 238 penetrates into the pressing space 237 , the higher the strand is compressed. The further the sealing element 238 is pushed out of the pressing space 237 , the lower the strand density. The level of compression is determined by the cylinder 239 shown schematically by the pressure in the pressure chamber 240 . Especially when it comes to strands with an angular profile, the path of the compression element to change the density is very small. With presses with a high output there is a risk that the compression control reacts too slowly. The invention eliminates this danger by using double-acting clamping cylinders 241 , the rod side 242 of which is subjected to a constant but adjustable pressure. The pressure of the cylinder side 243 is higher than the pressure of the rod side 242 and can determine the compression alone or preferably in cooperation with the tensioning cylinder 241 . Because the tubes 244 and 245 are of relatively large dimensions and the acceleration of the reduction in friction is accelerated by the pressure accumulators 246 , the friction can be reduced or increased almost instantaneously.

If the density is essentially determined by the clamping pressure of the chip cylinders 241 , the compression element 238 is kept constant at a suitable depth in the pressing space 237 . The compression force is measured, for example, by a pressure cell 247, and the chip force of the tensioning cylinder 241 is changed via an electronic control until the desired pressure in the pressure cell 247 and thus the desired strand density is obtained.

It is equally advantageous, particularly in the case of angular strands, not only to change the force of the tensioning cylinders 241 , but at the same time to change the immersion depth of the compression element 238 in the press chamber 237 by changing the pressure in the pressure chamber 240 .

In the embodiment, a reactor 248, and further a rigid preheating duct 24 a and a sequentially Abbindekanal 250 with a vacuum device 251 according to P 102 34 835.9 adjoins the baling chamber 237th Of course, all other types of heating channels can also be used. It is possible to modernize existing extrusion presses or extrusion tube presses by providing the heating duct with a vacuum device according to P 102 34 835.9, if necessary, and replacing the extrusion press with a continuous press according to P 101 01 386. This is particularly advantageous for round strands. In the exemplary embodiment, a mandrel 252 of any design is provided. Of course, extrusion can also be carried out without a mandrel. It is also possible and advantageous to integrate a second reactor as in FIG. 26 into the setting channel.

Fig. 28 shows a section through a continuous extruder. The pressing chamber 253 is cylindrical in the exemplary embodiment or it opens in the pressing direction at most slightly conically, for. B. by up to 1 mm in radius. The immersion depth of the compression element 254 is controlled by an adjusting element, e.g. B. a hydraulic cylinder 255 or spindles, the former is only shown schematically, determined in a suitable size and fixed changeable. As already described, the double-acting tensioning elements 256, supported by the pressure accumulators 257, can reduce the frictional pressure on the strand very quickly. An increase by the proportional pressure valve on the bottom line 258 is possible just as quickly. In this way, especially in the case of presses for round strands, the control of the compression of the strand can be completely taken over by the tensioning elements 256 or by their variable force.

The exemplary embodiment can process both a mixture of chips with glue and hardener at a customary temperature and a mixture at a higher temperature according to the invention, a mixture of H ₂ O and hardener being introduced into the strand by the reactor 259 . The amount of H ₂ O is limited in such a way that it results in a smoother strand surface and only partial heating of the strand. The necessary amount of hardener is added to the H ₂ O, which is necessary for the sudden start of the setting process. At a known distance from the reactor 259 , the invention arranges a second reactor 26 A through which the strand is brought to its setting temperature by means of H ₂ O. A vacuum device, not shown here, is also provided. The additional tensioning elements 261 only serve to compensate for any overpressure that may arise in the sealed region 261 of the H ₂ O entry. Due to the additional clamping elements 262 u. U., but no higher friction needs to be generated. Under no circumstances is the strand recompacted, as described by PCT / EP / 00/04852 and / or. PCT / EP / 06872 is proposed. Such a densification would also not be possible with round strands. The drawings show how much easier and more effective or safer the H ₂ O entry according to the invention compared to a steam station according to PCT / EP / 00/04852 and / or. PCT / EP / 06872. In the exemplary embodiment, a vacuum device 263 is provided and no mandrel is used. Of course, a mandrel of any design or described can be used to create hollow strands.

Claims (49)

1. A process for the production of strands from a mixture of small parts, in particular small wooden parts, in which the mixture is brought into the filling and pressing space of an extrusion or extrusion tube press and compressed therein by the force of a press ram or a helically wound compression element and into a subsequent binding device transported and sets in this, the small parts are glued with liquid or powdered glue, without hardener, get into the filling and pressing chamber, compacted in this and into a subsequent reactor and / or from a mandrel of a mixture of H ₂ O in the form of steam, hot water or evaporating hot water and hardener are penetrated in such a way that the hardener combines with the glue and the H ₂ O heats the strand completely or in part to the setting temperature and the setting process is started, characterized in that the small parts in one higher than usual temperature, of sth a 50 ° C to over 90 ° C in the filling and pressing room 2. The method according to claim 1, characterized in that the compression and their control by a press and mandrel cylinder combination according to the still unpublished application P 102 25 478.8. 3. The method according to claim 1, characterized in that the compression by a Press stamp with continuous piston tube and their control by an in an arbor arranged behind the press cylinder. 4. The method according to claim 1, characterized in that the compression force is reduced by a thorn that is through the strand, during its movement without Counterforce, is pulled. 5. The method according to claim 4, characterized in that with the strand entrained mandrel is withdrawn from / by the press ram into its starting position. 6. The method according to claim 1, characterized in that the compression by double-acting clamping cylinder is controlled, being on the rod side changeable, but constant pressure during the press stroke, which is caused by the pressure on the Pressure side is overcome in such a way that the density during the strand transport determining frictional force is exerted on the strand and during the breakaway phase in which the strand from static friction to sliding friction passes such a frictional force onto the Acts strand that the breakaway force corresponds approximately to the strand transport force, and during the remaining time in the press cycle, a higher pressure is present, which secures the strand clamps. 7. The method according to claim 1, characterized in that the compression by double-acting clamping cylinder is controlled, being on the rod side changeable, but constant pressure during the press stroke, which is caused by the pressure on the Pressure side is overcome in such a way that a density-determining, changeable frictional force is exerted on the strand and during the breakaway phase in which the Such a frictional force passes from the static friction to the sliding friction Acts that the breakaway force corresponds approximately to the strand transport force. 8. The method according to claim 1, characterized in that the strand density by the adjustable friction force of the clamping cylinder and the adjustable retention force of the Mandrel cylinder is determined. 9. The method according to claim 1, characterized in that the compression by a helically wound compression element according to DE 101 01 386 A1. 10. The method according to claim 1, characterized in that the strand through the, the filling and pressing chamber following reactor of a mixture of H ₂ O in the form of steam, hot water or evaporating hot water with a temperature of up to about 220 ° C. and hardener is penetrated to about 10% to about 40%, which results in a smoother and more compact surface, and the edge zone of the strand is dried in a subsequent heating zone of about 1.5 m to about 8 m in length and in whole or in part sets, and the strand thereby achieves a higher, transportable strength than immediately after the addition of H ₂ O and hardener. 11. The method according to claim 1, characterized in that the strand after drying the edge zone and / or its setting and / or at a distance of about 1.5 m to about 8 m in front of the front H ₂ O outlet opening of the reactor from outlet openings in the mandrel is penetrated by a mixture of H ₂ O in the form of steam, hot water or evaporating hot water with a temperature of up to approx. 220 ° C and hardener and brought to a setting temperature of approx. 85 ° C to approximately 100 ° C , and the introduced H ₂ O first condenses in the strand and releases its heat of condensation to the strand. 12. The method according to claim 1, characterized in that the strand after drying the edge zone and / or its setting and / or at a distance of about 1.5 m to about 8 m through a second reactor with H ₂ O in the form penetrated by steam, hot water or evaporating hot water with a temperature of up to approx. 220 ° C and hardener and brought to a setting temperature of approx. 85 ° C to approximately 100 ° C, and the introduced H ₂ O is first condensed in the strand and its Gives off condensation heat to the strand. 13. The method according to claim 10 and 11, characterized in that the Condensate located by a vacuum device according to the still unpublished application P 102 34 835.9 or DE 101 53 193.1 is evaporated. 14. The method according to any one of the preceding claims, characterized in that the pin hole is sealed by a sealing plug in such a way that none or only one little extraneous air is drawn into / through the line through the vacuum device. 15. The method according to any one of the preceding claims, characterized in that Piston presses according to DE 29 32 406 or according to one of the embodiments according to P 102 28 391.1 or P 102 33 121.9 which have not yet been published. 16. Device for performing the method according to claims 1 to 14, characterized characterized in that a filling and pressing room according to DE 29 32 498 or according to one of the embodiments according to the as yet unpublished applications P 102 28 391.1 or P 102 33 121.9 is used. 17. The apparatus according to claim 16, characterized in that the two guides ( 13 ) which are transverse to the pressing direction are designed as housings for two plunger cylinders each acting against one another and the piston tubes ( 22 ) which are guided and sealed by means of stuffing boxes ( 24 ) in trusses ( 23 ). are radially movable. 18. Device according to one of the preceding claims, characterized in that that the press stamp by a press and mandrel cylinder combination according to the still unpublished application P 102 25 478.8 is driven. 19. The apparatus of claim 2 and 3, characterized in that in one axis behind a press cylinder with a continuous piston tube through an intermediate tube that carries the path measuring devices or switching devices Mandrel cylinder is arranged with a continuous piston tube, the mandrel on the Piston tube is supported or fastened longitudinally. 20. Device according to one of the preceding claims, characterized in that that the distance measurement of the press and / or mandrel cylinder by magnetorestrictive Position sensors done. 21. Device according to one of claims 1 to 5, characterized in that the Press cylinder pulls the mandrel back to its original position. 22. Device according to one of claims 1 to 5, characterized in that the press ram ( 122 ) is driven by a double-acting hydraulic cylinder ( 123 ) via a press ram tube ( 121 ) and a pressure plate and the mandrel is suspended in the pressure plate in a longitudinally movable manner. 23. Device according to one of claims 1 to 5, characterized in that the press ram is driven by a double-acting hydraulic cylinder, the guides ( 134 ) in the guide surface are provided with 1 to 4 longitudinal grooves ( 170 ) which have a width of up to about 3 mm and have a depth of up to about 1 mm. 24. Device according to one of claims 1 to 5, characterized in that the press ram base plate ( 147 ) is divided in two and is fastened with a two-part locking ring ( 144 ) in a groove ( 141 ) on the piston rod. 25. Device according to one of claims 1 to 5, characterized in that the piston ( 148 ) via a two-part locking ring ( 144 ) in a groove ( 140 ) on the hollow piston rod ( 139 ) is screwed immovably. 26. The device according to claim 24, characterized in that the switching cam ( 149 ) is divided in two and is fastened with a two-part locking ring ( 145 ) in a groove ( 142 ) on the piston rod ( 139 ). 27. The device according to one of claims 1 to 5, characterized in that the press ram has two hollow piston tubes, the retraction side ( 154 ) being kept larger in diameter than that of the pressure side ( 152 ) and the two piston tubes ( 151 and 153 ) via an intermediate ring ( 158 ) and the two-part locking rings ( 156 ) in the grooves ( 157 ) by a corresponding tolerance design and by a recess ( 162 ) by the piston ( 159 ) and the piston nut ( 160 ) in such a way that can move the piston tubes radially so far that there is no static overdetermination. 28. Device according to one of claims 1 to 5, characterized in that a Thorn wholly or partially protrudes into / through the strand. 29. Device according to one of the preceding claims, characterized in that that the rear thorn strand is as long as possible but designed such that the friction between the strand and the rear mandrel run and, if available, the sealing plug, not or only slightly moved the strand when retracting the mandrel and not compresses. 30. Device according to one of the preceding claims, characterized in that between the front H ₂ O outlet opening of the reactor following the filling and pressing chamber and the rear H ₂ O outlet opening of the mandrel there is a distance of approximately 1.5 m to approximately 8 m exists. 31. The device according to claim 30, characterized in that the mandrel center piece (rod) ( 82 ) extends at least up to about the front end of the vacuum zone or up to about 2 m beyond. 32. Device according to claim 30, characterized in that the mandrel does not have front end of the binding channel protrudes. 33. Apparatus according to claim 30, characterized in that the mandrel center piece (rod) ( 82 ) is kept smaller in diameter by about 1 mm to about 10 mm than the rear mandrel run. 34. Device according to claim 30, characterized in that the in Sealing plugs following the mandrel center piece with a slight sliding fit or with an undersize of about 0.1 to about 1 mm in the strand and due to its length that Prevention of external air through the pinhole completely or largely prevented. 35. Device according to 30, characterized in that the sealing plug with up to about 5 sealing rings, e.g. B. commercially available piston rings, which is the pinhole caulk. 36. Device according to one of the preceding claims, characterized in that that the piston rods are hard chrome-plated and induction hardened and on the outside have a martensitic structure with a hardness of approx. 60 HCR and a core structure made of pearlite on the inside and own ferrite. 32. Device according to claim 36, characterized in that the hollow Piston rods made of commercially available hard chrome-plated, induction hardened precision shafts, e.g. B. the Bosch-Mannesmann-Rexroth. 38. Device for carrying out the method according to the preceding claims, characterized in that the strand density is determined by double-acting clamping elements (cylinders) ( 200 ) which press the movable heating angle / heating shells radially against the strand. 39. Apparatus according to claim 38, characterized in that in the rod side of the clamping elements ( 200 ) there is always an adjustable pressure which is constant during the pressing cycle. 40. Apparatus according to claim 39, characterized in that while the strand is not moving, a higher pressure is present on the bottom side ( 206 ) of the tensioning elements ( 200 ), which securely clamps the strand. 41. Device according to claim 40, characterized in that when the strand part to be newly formed has approximately reached its desired compression by about the time at which the strand has reached its transport speed, the pressure in the bottom side ( 206 ) of the tensioning elements ( 200 ) is such that the force of the press cylinder is about the same or not greater than the force with which it transports the strand. 42. Device according to claim 41, characterized in that the strand density is determined by the adjustable pressure in the bottom side ( 206 ) of the tensioning elements ( 200 ) after the strand has reached its transport speed until the press ram has reached its front end position. 43. Device according to claim 39, characterized in that when the new to forming strand part has approximately reached its desired density by the time in such a pressure in the strand has reached its transport speed Bottom sides of the clamping elements are applied so that the force of the press ram is approximately the same during this time Corresponds to the force with which the press stamp transports the strand. 44. Device for performing the method according to the preceding claims, characterized in that in the region of the second reactor ( 219 ) additional clamping elements are arranged which prevent the heating angles from moving apart during the H ₂ O injection into the strand but prevent the friction between the Do not increase the strand and the walls of the tying channel or only slightly. 45. Device for carrying out the method according to the preceding claims, characterized in that the individual binding channel sections are sealed by sealing brackets ( 235 ; 232 ) in such a way that little or no entry of extraneous air into the strand or no or only a small discharge of H ₂ O occurs from the setting channel. 46. Apparatus according to claim 30, characterized in that the H ₂ O outlet openings are designed as slots of approximately 0.2 to approximately 1 mm in width, which are spiral-shaped in the pressing direction at a distance of approximately 10 mm to approximately 100 mm Arbor are arranged and the number of slots is adapted to the amount of H ₂ O to be discharged. 47. Apparatus according to claim 30, characterized in that the H ₂ O outlet openings are designed as holes with a diameter of up to approximately 5 mm, which are arranged spirally in the pressing direction at a distance of approximately 10 mm to approximately 100 mm in the mandrel and the number of holes is adapted to the amount of H ₂ O to be discharged. 48. Device for performing the method according to the preceding claims, characterized in that with continuous presses the filling and pressing room cylindrical or with a cone of up to about 1 mm in the pressing direction. 49. Apparatus according to claim 48, characterized in that the depth of penetration of the Compression element in the press room of a continuous press by adjusting elements, z. B. cylinders or spindles is determined.