CN108274722B - Tail pressing device of on-line forming flaring module of corrugated pipe double-layer faucet - Google Patents

Abstract

The invention provides a bellows double-layer socket online forming expansion module tail compression device. The bellows ordinary module, the expansion module and the special module with a socket are connected in sequence from front to back. The double-wall corrugated pipe is extruded. The outlet head assembly is connected to the water jacket. The distance between the outer wall molten material extrusion die and the inner wall molten material extrusion die of the double-wall corrugated pipe extruder head is shortened to the position where the two die openings are immediately adjacent. The tail of the expansion module There is at least one special wavelet. The invention optimizes the existing technology, saves raw materials for the pipes produced, and can effectively improve the molding quality of the standard corrugated head. The entire pipe has good molding effect and good internal and external surface quality. It also enables the molding machine of the same specifications to use the fewest modules to produce the largest Effective length of double wall corrugated pipe with flare.

Description

Bellows double-layer socket online forming expansion module tail compression device

Technical field

The invention belongs to the field of bellows manufacturing, and particularly relates to a bellows double-layer socket online forming expansion module tail pressing device.

Background technique

In the field of corrugated pipe manufacturing, especially in the production process of large-diameter high-density polyethylene corrugated pipes, the double-walled corrugated pipe extrusion head is generally equipped with an inner wall molten material extrusion die and an outer wall molten material extrusion die. However, the two die openings are relatively far apart. The molten material extruded through the two die openings has problems such as long cooling time, poor double-layer welding, unstable product quality, and low production efficiency. Moreover, the structure of the double-wall corrugated pipe extruder head is complex and difficult to manufacture. and maintenance difficulties.

In view of this structure, some manufacturers on the market have proposed an improvement plan, which is to open a hole between the two die openings of the machine head that are far apart, so that during the pipe extrusion process, there is a gap between the inner and outer wall melt and the die opening of the machine head. The formed closed space is connected with an external compressed gas storage, so that the pressure change in the space is adjusted by the compressed gas storage.

The module is an important part of the molding machine on the plastic pipe production line. Its function is to solidify and shape the melt together with the molding machine head after the plastic melt is transported from the extruder head to the molding machine module cavity. The module cavity is The shape is designed according to the customer's requirements, so that when the solidified material comes out of the module cavity of the molding machine, the required plastic pipe is obtained.

In addition, a flare module is required when producing plastic pipes with a flare section. The starting end of the flare module for producing flare pipes is the head of the flare module, and the end of the flare module is the tail of the flare module. The tail of the traditional flared module is designed to be directly connected to the standard module. That is, after the entire pipe is formed, a part of the tail single-walled flared pipe is cut off to obtain the double-wall corrugated pipe head of the standard unit pipe. Since the expanded tail is directly connected to the head of the standard bellows, the uneven pressure of the gas in the cavity of the expanded section during the molding process of the expanded section will cause the gas to break through the standard bellows wall when producing standard double-walled corrugations. This leads to the defect of poor molding quality of the double-wall corrugated pipe head.

Contents of the invention

The technical problem solved by the present invention is to provide a bellows double-layer socket online forming expansion module tail pressing device with simple structure, reliable operation, good double-layer weldability, and good molding quality of the bellows part at the expanded tail. The time difference between the cooling of the molten material on the inner and outer walls is shortened, and the welding quality of the inner and outer walls of the bellows is improved.

The technical solution adopted by the present invention is: a bellows double-layer socket online forming expansion module tail compression device, which is connected in sequence from front to back by the cyclically running bellows ordinary module, the expansion module and the special module with a socket. The double-wall corrugated pipe extruder head assembly is connected to the water jacket. The distance between the outer wall molten material extrusion die and the inner wall molten material extrusion die of the double-wall corrugated pipe extruder head gradually shortens to the position where the two die openings are immediately adjacent. , the tail of the expansion module is equipped with at least one special wavelet. The special wavelet is then connected to the normal standard module. When cutting the entire pipe obtained in this way, you only need to cut off the tail of the flared section and the special wavelet part to get the starting end of the standard pipe.

The wave height of the special wavelet is smaller than the standard wave height, the wave distance is smaller than the standard wave distance, and the trough pressing point is lower than the trough pressing point of the standard bellows. This design allows the hot-melt material to be tightly locked by the special wavelet cavity on the module when the hot-melt material is squeezed by the molding gas after the pipe expansion section is formed. Preferably, two special wavelets are used to form a double lock. The tight guarantee ensures that even if the pressurized gas breaks through the hot-melt material and causes defects during the molding process of the special wavelet, good waveform quality can be guaranteed because the gas is released to a certain pressure and is then molded through the standard waveform. The flared tail and the two special wavelet parts are the parts that will be cut off, so even if the quality of the special wavelet is not good, it will not affect the quality of the normal pipe.

The upper outer die lip and the lower outer die lip of the double-wall corrugated pipe extrusion head assembly are connected together to form the outer die lip. The gap after assembly of the outer die lip and the middle die lip is the outer wall melt extrusion die, and the middle die lip The gap after assembly with the inner die lip is the inner wall molten material extrusion die.

An inclined pipeline is provided in the middle die lip, and the inner wall melt extrusion die and the outer wall melt extrusion die are adjacent to the upper and lower sides of the inclined pipeline.

There is a cooling rod core on the water jacket, and a vertical pipeline is installed between the water jacket and the inner die lip. Compressed air is sent through the vertical pipeline between the cooling rod core and the inner wall molten material. Under the action of internal air pressure, The inner wall molten material is deflected in the direction of the outer wall molten material, and the air between the inner and outer wall molten materials is gradually discharged through the vertical pipeline, and the inner and outer wall molten materials are attached and welded together.

The bellows ordinary modules, expanded modules and special modules with sockets are equipped with vacuum holes or multiple groups of vacuum holes and cooling water channels or multiple groups of cooling water channels. The inner and outer wall melt materials have vacuum holes on the internal pressure and forming modules. Under the action of adsorption, they fit together to the contour curve of the socket of the molding module. The heat is taken away by the circulating cooling water in the cooling channel on the molding module and cooled and shaped into a double-layer socket area.

The beneficial effects of the present invention are that it optimizes the existing technology, saves raw materials for pipes produced using the structure of the present invention, can effectively improve the molding quality of the standard corrugated head, has good molding effect of the entire pipe and good internal and external surface quality, and achieves the same The gauge forming machine produces flared double-wall corrugated pipes of maximum effective length using a minimum number of modules.

In addition, it has good mechanical properties, stable quality and high production efficiency for online manufacturing of double-layer sockets. The double-wall corrugated pipe extrusion head has a simple structure, convenient production, processing and maintenance, and reliable operation.

Description of the drawings

Figure 1 is a schematic diagram of the tail compression device of the bellows double-layer socket online forming expansion module.

Figure 2 is an enlarged view of Figure 1A.

Figure 3 is a working principle diagram of the tail compression device of the bellows double-layer socket online forming expansion module.

Figure 4 is an enlarged view of Figure 3B.

Reference symbols: 1-General module of bellows 2-Cooling channel 3-Expansion module 4-Vacuum hole 5-Special module with socket 6-Outer wall melt extrusion die 7-Incline pipeline 8-Inner wall melt Extrusion die mouth 9-vertical pipe 10-inner cooling channel; 11-cooling rod core 12-water jacket 13-flaring module tail 14-special wavelet 15-upper outer mold lip 16-lower outer mold lip 17-double Wall corrugated pipe extrusion head 18-middle die lip 19-inner die lip 20-pipe 21-flaring module head 22-flaring part tail wave 23-standard wave

Detailed ways

The present invention will be further explained below in conjunction with the accompanying drawings.

As shown in Figures 1 and 2, the present invention is a bellows double-layer socket online forming expansion module tail compression device, which consists of a cyclically operating bellows ordinary module 1, an expansion module 3 and a special module with a socket 5. The double-wall corrugated pipe extruder head 17 assembly is connected to the water jacket 12 in sequence, and the distance between the outer wall molten material extrusion die 6 and the inner wall molten material extrusion die 8 of the double-wall corrugated pipe extruder head 17 is It is gradually shortened to the position where the two die openings are immediately adjacent, and the tail of the expansion module 3 is provided with two special wavelets 14 . The special wavelet 14 is then connected to the normal standard wavelet 23. When cutting the entire pipe thus obtained, only the tail of the flared section and the two special wavelet 14 parts need to be cut off to obtain the starting end of the standard pipe. The ineffective length of the expansion section of the expansion module 3 is shortened, saving materials, and due to the existence of the special wavelet 14, the hidden danger of poor molding quality in the head of the standard bellows is eliminated here, thus ensuring double-wall corrugation. The molding quality of the tube. It avoids excessive removal of the standard corrugated pipe head with poor molding quality, saving production time and production raw materials. On the production line, the continuously produced double-wall corrugated pipes are cut at the double-layer socket and special wavelet 14 area. At this time, each double-wall corrugated pipe has a double-layer socket area, so that during construction, the double-walled corrugated pipes Corrugated pipes can easily complete the butt connection.

When designing the expansion module 3, the ineffective length of the expansion end is shortened to reserve a position for arranging the special wavelets 14, as shown in Figures 3 and 4. Two special wavelets 14 are designed at this position, occupying the effective length of the expanded section. The wave height of the special wavelet 14 is smaller than the standard wave height, the wave distance is smaller than the standard wave distance, and the trough pressing point is lower than that of the standard wave 23. Preferably, the wave height of the special wavelet 14 is 0.3 to 0.8 times that of the standard wave, the wave distance is 0.3 to 0.8 times that of the standard wave, and the trough pressing point is 0.5 mm to 2 mm lower than the trough pressing point of the standard wave 23 . This design allows the hot-melt material to be tightly locked by the special wavelet 14 cavity on the module when the hot-melt material is extruded by the forming gas after the pipe expansion section is formed, and the two special wavelets 14 form a double lock. The tight guarantee ensures that even if the pressurized gas breaks through the hot-melt material and causes defects during the molding process of the special wavelet 14, since the gas is released to a certain pressure and is then molded through the standard wave 23, good waveform quality can be guaranteed. The tail 13 of the flare module and the special wavelet 14 are parts that will be cut off, so even if the quality of the pipe at the special wavelet 14 is not good, it will not affect the quality of the normal pipe 20 .

The upper outer die lip 15 and the lower outer die lip 16 of the double-wall corrugated pipe extrusion head 17 assembly are connected together to form an outer die lip. The gap after assembly between the outer die lip and the middle die lip 18 is the outer wall molten material extrusion die. 6. The gap between the middle die lip 18 and the inner die lip 19 after assembly is the inner wall molten material extrusion die opening 8.

The middle die lip 18 is provided with an inclined pipeline 7, and the inner wall melt extrusion die opening 8 and the outer wall melt extrusion die opening 6 are adjacent to the upper and lower sides of the inclined pipeline 7.

The water jacket 12 is provided with a cooling rod core 11, and a vertical pipeline 9 is provided between the water jacket 12 and the inner mold lip 19. Compressed air is sent between the cooling rod core 11 and the inner wall molten material through the vertical pipeline 9. Under the action of internal air pressure, the inner wall molten material is deflected in the direction of the outer wall molten material, and the air between the inner and outer wall molten materials is gradually discharged through the vertical pipeline 9, and the inner and outer wall molten materials are attached and welded together.

The bellows ordinary module 1, the expansion module 3 and the special module with a socket 5 are provided with multiple sets of vacuum holes 4 and multiple sets of cooling water channels 2. Under the action of internal pressure and the adsorption of the vacuum holes 4 on the molding module, the molten material on the inner and outer walls adheres to the contour curve of the socket of the molding module. Its heat is taken away by the circulating cooling water in the cooling channel 2 on the molding module and cooled. It is shaped into a double-layer socket area.

When the device is working, the outer wall molten material extrusion die 6 and the inner wall molten material extrusion die 8 on the double-wall corrugated pipe extruder head 17 are relatively close to each other (refer to the enlarged picture A, the distance between the two die openings Only the width of a wavelet), the molten material extruded through the two die openings has a short cooling time, and the temperature difference between the inner and outer layers of molten material is small, so the double-layer molten material is well welded and the product quality is guaranteed, and the double-wall corrugated pipe is extruded The machine head 17 has a simple structure and is easy to process. A water jacket 12 is installed in front of the double-wall corrugated pipe extruder head 17, which is used to cool the inner wall of the formed pipe.

When manufacturing the double-layer socket part, the compressed air passes through the vertical pipe 9 and enters between the cooling rod core 11 and the inner wall molten material in the inner wall molten material extrusion die 8. Under the action of internal air pressure, the inner wall molten material flows toward the outer wall. The outer wall melt material in the melt extrusion die opening 6 is offset, the air between the inner and outer wall melt materials is gradually discharged through the vertical pipeline 9, the inner and outer wall melt materials are attached and welded together, and the internal pressure and the expansion module 3 Under the adsorption action of the vacuum holes 4 on the molding module, it fits to the contour curve of the socket of the molding module. Its heat is taken away by the circulating cooling water in the cooling channel 2 on the ordinary module 1 and the expanded module 3 and gradually cools and shapes. It becomes a double-layer socket area.

To produce pipes with the same diameter specifications, the general module design and arrangement method is to arrange several pairs of conventional corrugated modules in sequence, followed by a pair of expansion modules. The expansion starting end to the end of the expansion module covers the entire module. During the pipe forming process, all modules move periodically according to the predetermined trajectory, thereby forming a whole section of pipe connected with the corrugated section and the flared section. Then, the tail of the flared section and several sections of corrugated pipe of a certain length immediately behind it are cut off online using a cutting saw on the pipe production line, thereby obtaining an entire plastic corrugated pipe with a flared section of the same length.

When the present invention optimizes the design of the module, the special wavelet 14 at the end of the expansion module is connected to the end 13 of the expansion module. When the two special wavelets 14 behind the socket and the ordinary bellows part are manufactured online, when the bellows ordinary module 1 Or the special module 5 with a socket runs to the position of the molten material extrusion die of the extruder. The compressed air enters the inner and outer wall molten material cavity through the pipeline 7. Under the action of air pressure, the inner wall molten material is in contact with the cooling rod core 11. Together, the outer wall molten material fits onto the cross-sectional contour curve of the molding module bellows 1. The heat of the inner and outer walls is taken away by the circulating water in the inner cooling channel 10 and the cooling channel 2 respectively. The inner and outer walls solidify together after cooling.

As shown in Figure 3, the corrugated pipe 20 with a flare that needs to be formed is a plastic double-walled corrugated pipe with a flare formed online through the module on the molding machine. There are several common modules 1 for the corrugated pipe, a flare module 3 and a special module with a socket. Module 5 is installed on the mold base of the molding machine in a certain order. All modules move on the molding machine in sequence with a fixed movement trajectory. Taking one of the modules as a reference, when the module appears from a certain position, it will appear at that position next time. At this time, all modules complete an operation cycle, and the formed pipe at this time is a fixed unit length pipe. By repeating this cycle, the uninterrupted online production of pipes can be completed. When the pipe passes between the tail of the expansion module and the next standard module, due to the existence of two special wavelets 14, the corrugated section of poor quality that may appear during the forming process is limited to the position where the special wavelets 14 appear, and The bellows expanded section tail 13 and the special wavelet 14 are parts that need to be cut off during the design, thereby ensuring the molding quality of the entire bellows.

Claims (1)

1. The utility model provides a corrugated pipe double-deck bell and spigot on-line forming flaring module afterbody closing device, is connected in proper order from front to back by the common module of corrugated pipe (1) of circulation operation, flaring module (3) and special module (5) of taking the socket, and double-walled bellows extruder head (17) are connected with water jacket (12), and the distance of outer wall melt extrusion die mouth (6) and inner wall melt extrusion die mouth (8) of double-walled bellows extruder head (17) shortens gradually to these two die mouthful next-door neighbour's position, its characterized in that: the tail of flaring module (3) is equipped with at least one special wavelet (14), the wave height of special wavelet (14) is less than standard wave height, and the wave distance is less than standard wave distance, and the wave trough pressure point is lower than standard bellows wave trough pressure point, outer die lip is constituteed together with outer die lip (16) on last outer die lip (15) of double-walled bellows extruder head (17), clearance after outer die lip and middle die lip (18) assembly is outer wall melt extrusion die orifice (6), clearance after middle die lip (18) and interior die lip (19) assembly is inner wall melt extrusion die orifice (8), be equipped with cooling stick core (11) on water jacket (12), be equipped with vertical pipeline (9) between water jacket (12) and the interior die lip (19), be equipped with multiunit vacuum-pumping hole (4) and multiunit cooling water passageway (2) on bellows ordinary module (1), flaring module (3) and the special module (5) of taking the socket, be equipped with inclined pipeline (7) in middle die lip (18), the inner wall (8) and the melt extrusion die orifice (8) of both sides of extruding on the inclined pipeline (7).