RU2133670C1 - Method and apparatus for manufacture of profiled products from polymeric composite materials - Google Patents

Abstract

FIELD: production of profiled tubular and rodlike articles working in twisting, tension, compression and inner excessive pressure mode from polymeric composite materials by pulltrusion method. SUBSTANCE: method involves directing predetermined number of threads 8 with zero-lift angle from bobbin holder 1 through impregnating device 2 and system of auxiliary spinnerets 9 along mandrel 7 fixed in braided module 5; passing a portion of threads through special devices in braided module 5 with further insertion of these threads into interweaving unit; withdrawing another portion of threads 10 from bobbins 11 in braided module 5; directing threads 10 through restrictor 12, impregnating device 6 and heated forming spinneret 3 with further fixing on bar of pulling device 4; pouring prepared binder into impregnating devices 2 and 6; switching pulling device 4 and 5-10 min after that putting braided module 5 into operation; obtaining ready product 7', 6''. In case wound layers are used in reinforcing structure, auxiliary winder with winding machine 13 may be employed. Tapes 14 made as woven forms or groups of threads are withdrawn from bobbins of winding machine 13. Winding unit is rotated for winding pack with tapes or threads at an angle of 75-87 deg. Winding unit is mounted between heated forming spinneret 3 and impregnating unit 6. In case of necessity for additional impregnation of winding tapes 14, impregnation bath 6' may be positioned between heated forming spinneret 3 and winding machine 13. Units 5, 6, 6', 12, 13 and 3 from which module is formed may be repeatedly combined. EFFECT: increased efficiency and enhanced reliability in operation. 12 cl, 2 dwg

Description

 The invention relates to methods for manufacturing profile products from polymer composite materials (PCM) by pultrusion and devices for their implementation and can find application in various sectors of the economy.

 A known method of manufacturing pipes from PCM by vertical stretch pultrusion and a device for its implementation (US patent N 3374132, NKI 156 - 171, 1968), in accordance with which the fibrous base located on the mandrel is impregnated with a binder. The method involves a spiral winding with different pitch and angle in four different cross-sectional planes in height with the subsequent application of unidirectional threads on the surface of the cross-section. The entire package is closed on the surface with a tape supplied along the axis of the broach, and after an additional impregnating device enters the forming die.

 The pulling is carried out using the pulling device installed after the die, vertically down. The die is heated by supplying hot fluid to each half of the die.

 The disadvantages of this method and device include their relative high cost, the need to build special buildings, high capital costs during installation, as well as the difficulty in maintenance.

A known method of producing profiles by pultrusion and installation with a horizontal hood for its implementation (Installation for the manufacture of profiled fiberglass products by continuous drawing, "Shipbuilding", 1979, N 10, S. 32 - 36 - prototype), according to which some layers are laid longitudinally to the axis of the hood, others are wound with reduced density diagonally at an angle of 70 - 85 ^o . These operations can be repeated. A layer of fibers oriented along the axis of the broach is laid on top of the layers thus laid out. In this case, the rigid compression of the longitudinal layers to the mandrel is performed with a small gap between the fiberglass and the laying surface. The glass fiber on the mandrel is impregnated with an excess amount of the binder layer by layer in the order of their application, and the excess of the binder is preserved until the packet is crimped in front of the die. To this end, the sealing and sealing of the impregnation zone is carried out due to elastic compression, increasing along the length of the mandrel. The deformation of the layers in the profile in the mandrel of a variable shape is carried out by transferring pressure directly to the outer longitudinal layers of reinforcing fiberglass.

 The specified method is carried out on the installation, including disk creel and wrappers with distribution rings; a cantilevered cylindrical mandrel with an end of a variable profile and a constant perimeter of cross sections; impregnation baths covering the mandrel, which are a crimping unit with a binder chamber, detachable heated dies, a heat treatment chamber, broaching, cutting and rolling table mechanisms.

 Thin-walled profiles made in this way have high strength and stiffness; as a rule, they do not have longitudinal cracking. These profiles work well for compression and tension, but they are unsuitable for transmitting rotational motion. The reason for this is the reinforcement structure.

 The present invention is the manufacture of rods and pipes from PCM, operating in difficult stress conditions, namely during torsion, i.e. under compressive, tensile and bending loads.

 To solve this problem, the method of manufacturing profile products from PCM by pultrusion involves removing the reinforcing fiber from the creel, oriented along the broaching axis, impregnating it in a bath with a binder, spinning, forming a package and curing it in a heated forming die. Before entering the heated forming die, the formed package of the reinforcing material impregnated with a binder is braided continuously with the introduction of a reinforcing material impregnated with a binder with a zero angle into the weave zone. The PCM package formed after braiding is introduced into the heated forming die, where the profile is finally formed and cured.

 When forming highly loaded profiles from PCM, the package can be formed in several stages sequentially in a continuous mode, laying longitudinal and transverse or one transverse layers of reinforcing material, while the braid layers of the second and each subsequent layer of reinforcing material are applied to the partially cured surface of the workpiece obtained in the previous stage , which allows you to have a relatively short mandrel, reaching only the first curing unit.

 The formation of hollow products can be carried out on a stationary mandrel relative to the package. A variant of this is the method when a preformed pipe is inserted inside the bag while the bag is being inserted, and the process is continuous by feeding the next pipe into the weaving zone and connecting it to the previous butt. The adhesive used is a binder squeezed out of the bag.

 The pipe introduced into the package can be formed at the same time as the rest of the operations, moreover, this pipe is aligned with the rest of the line and is at the beginning of the formation line.

The impregnation of the braiding layers can be carried out in a heated roller impregnating device at a temperature of not lower than 30 ^o C.

 Installation for implementing the inventive method for manufacturing profile products from PCM by pultrusion contains creel, impregnation bath, heated forming die and pulling device. In front of the forming die, a braid module (OM) is additionally installed in series, equipped with a device providing the introduction of a thread with a zero angle of inclination into the weave zone and a roller-type impregnation device. It is advisable to arrange the axis of symmetry of OM horizontally. The installation may contain at least two modules, each of which includes an OM, an impregnating device, and a heated die, while the forming die of each subsequent module has a profile section area larger than the previous one by a predetermined amount. In front of the braiding device of the first module, a fixedly long mandrel can be installed, the centering of which is carried out by the centering mechanism OM.

 After the braiding and impregnating devices, a winding device can be installed.

 To form a unidirectional pipe in a single cycle, a creel and an impregnating device can be installed in front of the first OM.

A feature of the proposed method is the combination of unidirectional (along the axis) reinforcement with a bulk (braid) imposed on top of unidirectional layers, a layered combination of further unidirectional and volume reinforcement or only multilayer volume reinforcement is possible. One or another variant of the combination of reinforcing layers is selected based on the functional purpose of the profile, however, the main (first) unidirectional reinforcement layer is present everywhere, which is caused by the essence of the molding method. In addition, unidirectional reinforcement ensures the stability of the profiles during compression and tensile operation while transmitting torque when they absorb tensile and compressive forces. Volume reinforcement can be a combination of reinforcement layers with a thread at angles of ± (30 - 60) ^o with a thread with a zero angle of inclination in the weave, over this layer winding layers can be laid at angles of ± (75 - 87) ^o , which are made with tape on basis of fabric or a combination of a group of threads with one orientation. Such combinations can solve the problems of obtaining pipes when they work under excessive pressure, while simultaneously experiencing the effect of torque. The sequence and order of application of the reinforcing layers is determined by the functional feature of the profile service. This also determines the design features of the installation, when, for the implementation of a particular option, this or that module or their group is installed at the appropriate position. This approach allows you to expand the capabilities of the main base pultruder installation.

 In FIG. 1 schematically shows an installation for the manufacture of profile products from PCM, containing module A, is a general view; in FIG. Figure 2 schematically shows an installation option with an OM and a winding assembly (module B) - general view; in FIG. Figure 3 schematically shows an installation including an additional module B, which provides the possibility of obtaining a unidirectional pipe or rod, a general view.

 The installation for the manufacture of PCM profile products includes creel crepes 1, an impregnating device 2, a heated forming die 3, a pulling device 4. A braid module (OM) 5 is installed in front of the heated forming die 3. An additional impregnating roller device is installed between the heated forming die 3 and OM 5 type 6. The installation may contain two or more modules A, each of which includes OM 5, an impregnating device 6, a heated forming die 3. In the first order of module A, before ny lengthy mandrel 7.

 In the manufacture of profile products from PCM, first refuel as follows. The estimated number of threads 8 with a zero angle of inclination from creel 1 is passed through an impregnating device 2 and a system of auxiliary dies 9 along the mandrel 7, mounted in the OM.

 At the same time, for the subsequent introduction into the weave assembly of threads with a zero angle of inclination, a predetermined number of them is passed through a special device of the braiding module 5 and a stopper 12, connecting them to the main threads having a zero angle of inclination, and all the threads with a zero angle of inclination are fixed on the rod of the pulling device 4 (not shown).

 The second part of the threads 10 are selected from the spool 11 OM. The threads 10, passed through the limiter 12, the impregnating device 6 and the die 3, is fixed on the rod of the pulling device 4.

 The prepared binder is poured into the impregnating devices 2 and 6. Turn on the pulling device 4 and after 5 to 10 minutes turn on OM 5. 7 ', 6' '- the finished profile.

In the case of using winding layers in the reinforcement structure, an additional winding assembly (Fig. 2) is introduced, comprising a winding machine 13, with the spool of which the tapes 14 are removed in the form of woven shapes or a group of threads. When the winding assembly rotates, the package is wrapped with ribbons or threads at an angle of ± (75 - 87) ^o . A winding assembly is installed between the die 3 and the impregnation assembly 6.

 If necessary, additional impregnation of the winding tapes 14 between the die 3 and the winding machine 13 can be additionally installed impregnating bath 6 '. Combinations of nodes 5, 6, 12, 13, 6 'and 3 constituting the module B can be repeated many times.

 Example 1. Production by pultrusion of a ⌀ 3 mm rod from PCM with a binder based on epoxy resin ECD and glass roving as a filler. From the creel 1, a bundle of bundles with a zero angle of inclination is selected, consisting of two bundles of RBD 13-2562, and 60 threads of the VMPS-6 brand are passed through an impregnating device. Then, the VMPS-6 filaments pass through a special device of the braiding module 5 and are connected to two strands of RBM 13-2562 passing through the OM 5 center, where 60 VMPS-6 filaments 10 with the OM 5 shuttle spool are added to them, then the bundles enter through the limiter 12 and the impregnating device 6 into the heated forming die 3 and are mounted on the rod of the pulling device 4.

The drawing process is carried out at the following process parameters:
- the temperature of the binder in the impregnation bath is 40 - 60 ^o C;
- rod pulling speed - 0.2 - 0.35 m / min;
- the temperature of the heater forming die - 190 - 220 ^o C.

 The axis of symmetry of the OM and the axis of symmetry of the working channel of the die coincide.

 Example 2. The manufacture of pultruded pipes from PCM ⌀ 35.6 mm with an inner diameter of 27 mm is similar to the manufacture of example 1.

The formation of the inner hole is carried out using the mandrel 7, which is fixed motionless. The installation contains a second impregnating device 6 roller type, consisting of 4 pairs of rollers arranged in pairs at an angle of 90 ^o C, and a system of auxiliary dies 9. To reinforce the product form a package of 260 harnesses RBD 13-2562 and 100 harnesses RVMI 10-420 -80, to which they are added with OM shuttle spool 5 100 100 RVMI harnesses 10-420-80. The movement pattern of the harnesses RVMI 10-420-80 as in example 1 for threads grade VMPS-6.

The drawing process is carried out at the following process parameters:
- the temperature of the binder in the impregnation bath is 40 - 60 ^o C;
- pipe drawing speed - 0.1 - 0.2 m / min;
- the temperature of the heater forming die - 190 - 220 ^o C.

 Example 3. Similar to example 2, but instead of the mandrel to obtain an inner hole, a semi-finished pipe with an inner diameter of 25 mm made of fiberglass with a wall thickness of 1 mm is used. The pipe is placed in the center of the braiding module 5, along it 146 bundles of RBD 13-2652 (8) and 100 bundles of RVMI 10-420-80 are laid, 100 bundles of RVMI 10-420-80 are selected with the spool OM 5, the rest as in example 2. The movement pattern of the harnesses RVMI 10-420-80 as in example 1 for threads grade VMPS-6.

 The fibers passed through the impregnating device 2 and the heated spinning die 3 are mounted on the rod of the pulling device 4. Centering of the pipe with respect to the heated spinning heated die 3 is ensured by uniform distribution of fiber along the generatrix of the pipe, auxiliary devices and OM due to the uniform tension of the threads during braiding.

 As the pipe is "developed" end-to-end, the next pipe is installed to it. The joint between the pipes is glued due to excess binder in the unidirectional fiber. Thus, an endless pipe with a braid is provided.

 Example 4. The manufacture of pultruded pipe ⌀ 35 mm of fiberglass on a binder based on epoxy resin ECD with an inner diameter of 25 mm (Fig. 3).

 59 bundles of RBD 13-2520 are selected from creel 15, passed through an impregnation bath 16 and a heated forming die 17 having a working channel with a diameter of 27 mm and a mandrel with an outer diameter of 25 mm, through the center of creel crest 1, where 260 bundles of RBD 13- are attached to them 2520 and 100 bundles of RVMI 10-420-80 from creel 1 passing through the impregnation bath 2, then 100 bundles of RVMI 10-420-80 are selected with the OM 5 spool, and the bundle with all fibers is passed through the forming die 3 and mounted on the pulling rod devices 4. The movement pattern of the harnesses RVMI 10-420-80 as in example 1 for n Iteme brand VMPS-6.

Technological parameters:
- the temperature of the binder in the impregnation bath is 30 - 60 ^o C;
- pulling speed - 0.1 - 0.2 m / min;
- the temperature in the forming die 17 - 180 - 200 ^o C;
- the temperature in the forming die 3 - 190 - 220 ^o C.

 Example 5. Fabrication by pultrusion of a ⌀ 35 mm pipe made of fiberglass with a binder based on epoxy resin ECD with an inner diameter of 25 mm using a winding. Example 4 is repeated, but 200 strands of RBD 13-2520 are selected from creel 1, and after the impregnation device 6 (Fig. 2), 3 tapes 14 from T-10 fabric with a thickness of 0.2 mm and a tape width of 20 mm are selected from winding machine 13 further fully repeats example 4.

 Combining models A, B or C due to the multi-stage sequence, a predetermined structure for reinforcing the shaft or pipe is achieved.

Claims (12)

 1. A method of manufacturing profile products from polymer composite materials, including removing the reinforcing material from the creel, impregnating it in a bath with a binder, spinning, forming a package and curing it in a heated forming die, characterized in that before entering the heated forming die, a formed bag of impregnated the binder of the reinforcing material is braided in a continuous mode with the introduction of a reinforcing material impregnated with the binder with a zero angle into the weave zone.  2. The method according to claim 1, characterized in that the formation of the package is carried out in stages with sequential application of layers of reinforcing material, while the braid layers of the second and each subsequent layer of reinforcing material are applied to the partially cured surface of the workpiece obtained in the previous step.  3. The method according to claim 1, characterized in that when forming the hollow products at the initial stage of forming the package, a stationary mandrel is inserted inside it.  4. The method according to claim 1, characterized in that when forming the hollow products at the initial stage, a preformed pipe is introduced inside the bag, while the process is continuous by feeding another identical pipe to the weaving zone connected to the previous butt. 5. The method according to claims 1 to 4, characterized in that the bag braided with reinforcing material is impregnated in a heated roller impregnating device at a temperature not lower than 30 ^o C.  6. The method according to claim 4, characterized in that the pipe introduced into the packet is formed at the same time as the rest of the operations, is located coaxially with the rest of the line and is located at the beginning of the formation line.  7. Installation for the manufacture of shaped products from polymer composite materials containing creel, impregnating bath, heated forming die and pulling device, characterized in that in front of the forming die is additionally sequentially installed braid module and impregnating device of roller type.  8. Installation according to claim 7, characterized in that the axis of symmetry of the braid module is horizontal.  9. Installation according to claims 7 and 8, characterized in that it contains at least two modules, each of which includes a braid module, an impregnating device and a heated die, while the forming die of each subsequent module has a profile section area larger than the previous by a given amount.  10. Installation according to claims 7 to 9, characterized in that a fixedly long mandrel is installed in front of the braiding device of the first module, which is centered by the centering mechanism of the braiding module.  11. Installation according to claims 9 to 10, characterized in that after the braiding and impregnating devices a winding device is installed.  12. Installation according to claims 7, 9 to 11, characterized in that when forming a unidirectional pipe in a single cycle, a creel and an impregnating device are additionally installed in front of the first braiding module.

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