Production equipment and manufacturing method of ultrahigh molecular polyethylene pipe
阅读说明:本技术 超高分子聚乙烯管材生产设备及制造方法 (Production equipment and manufacturing method of ultrahigh molecular polyethylene pipe ) 是由 郝斌 江厚建 于 2020-06-08 设计创作,主要内容包括:本发明提供一种超高分子聚乙烯管材生产设备,包括塑化挤出系统、液压系统、成型系统、控制系统;成型系统包括管材模具和冷却装置;管材模具包括主模具、芯模和成型管模,成型管模套设在芯模外,主模具设置于芯模和成型管模的前端,用于使从塑化挤出系统挤出的物料以直线流动进入芯模和成型管模之间;成型管模用于成型超高分子聚乙烯管材的外壁;芯模套设于成型管模的内部,用于成型超高分子聚乙烯管材的内壁;冷却装置包括第一冷却元件和第二冷却元件,第一冷却元件用于成型管模的冷却降温,第二冷却元件用于芯模的冷却降温,冷却装置提供55℃~85℃的冷却温度使得成型管模与芯模的温度保持相同。本发明还提供一种超高分子聚乙烯管材的制造方法。(The invention provides a production device of an ultra-high molecular polyethylene pipe, which comprises a plasticizing extrusion system, a hydraulic system, a forming system and a control system; the molding system comprises a pipe mold and a cooling device; the pipe mold comprises a main mold, a core mold and a forming pipe mold, wherein the forming pipe mold is sleeved outside the core mold, and the main mold is arranged at the front ends of the core mold and the forming pipe mold and is used for enabling materials extruded from a plasticizing extrusion system to flow between the core mold and the forming pipe mold in a straight line; the forming pipe die is used for forming the outer wall of the ultra-high molecular polyethylene pipe; the core mould is sleeved in the forming pipe mould and is used for forming the inner wall of the ultrahigh molecular polyethylene pipe; the cooling device comprises a first cooling element and a second cooling element, the first cooling element is used for cooling the formed pipe die, the second cooling element is used for cooling the core die, and the cooling device provides a cooling temperature of 55-85 ℃ to keep the temperature of the formed pipe die and the temperature of the core die the same. The invention also provides a manufacturing method of the ultra-high molecular polyethylene pipe.)
1. The production equipment of the ultra-high molecular polyethylene pipe is characterized by comprising a plasticizing extrusion system, a hydraulic system, a forming system and a control system;
the molding system comprises a pipe mold and a cooling device;
the pipe mold comprises a main mold, a core mold and a forming pipe mold, the main mold is arranged at the front ends of the core mold and the forming pipe mold along the advancing direction of materials, the forming pipe mold is sleeved outside the core mold, and the main mold is used for enabling the materials extruded from the plasticizing extrusion system to flow into the space between the core mold and the forming pipe mold in a straight line; the forming pipe die is used for forming the outer wall of the ultrahigh molecular polyethylene pipe; the core mold is sleeved in the forming pipe mold and is used for forming the inner wall of the ultrahigh molecular polyethylene pipe;
the cooling device comprises a first cooling element and a second cooling element, the first cooling element is used for cooling the formed pipe die, the second cooling element is used for cooling the core die, and the cooling device provides a cooling temperature of 55-85 ℃ so that the formed pipe die and the core die can keep the same temperature.
2. The apparatus for producing ultra-high molecular polyethylene pipe as claimed in claim 1, wherein the plasticizing extrusion system comprises a cylinder and a push rod, and the hydraulic system is used for driving the push rod to push the material plasticized in the cylinder into the molding system.
3. The apparatus for producing ultra-high molecular polyethylene pipe according to claim 1, wherein the core mold has a hollow inner cavity, and the second cooling element comprises a second cooling circulation line, and the hollow inner cavity is communicated with the second cooling circulation line for circulating a cooling medium through the hollow inner cavity to cool down the core mold.
4. The production equipment of the ultra-high molecular polyethylene pipe material as claimed in claim 1, wherein the main mold comprises an outer mold sleeve and a spreader cone sleeved inside the outer mold sleeve, the tip of the spreader cone faces the plasticizing extrusion system, a passage for the material to flow is arranged between the outer mold sleeve and the spreader cone, so that the material enters the space between the core mold and the forming pipe mold from the plasticizing extrusion system, and the taper of the spreader cone is 50-55 degrees.
5. The production equipment of the ultra-high molecular polyethylene pipe material as claimed in claim 1, wherein the plasticizing extrusion system is sequentially divided into a feeding area, a melting area, a first homogenizing area, a second homogenizing area, a third homogenizing area and a joint area with different temperatures along the material advancing direction, and the heating temperature of the feeding area is 215-220 ℃; the heating temperature of the melting zone is 220-225 ℃; the heating temperature of the first homogenizing zone is 225-230 ℃; the heating temperature of the second homogenizing zone is 230-235 ℃; the heating temperature of the third homogenizing zone is 235-240 ℃; the heating temperature of the joint area is 240-245 ℃.
6. The apparatus for producing ultra-high molecular polyethylene pipe as claimed in claim 1, wherein the main mold is sequentially divided into a first temperature zone and a second temperature zone along the material advancing direction, the first temperature zone is 240 ℃ to 245 ℃, and the second temperature zone is 235 ℃ to 240 ℃.
7. A method for manufacturing an ultra-high molecular weight polyethylene pipe by using the ultra-high molecular weight polyethylene pipe production equipment as claimed in any one of claims 1 to 6, comprising the steps of:
plasticizing a material by heating of the plasticizing extrusion system and extruding the plasticized material into the molding system; and
and the plasticized material enters the core mold and the forming pipe mold through the main mold for forming, and the outer wall and the inner wall of the formed pipe are simultaneously cooled and shaped through the cooling device.
8. A method for manufacturing an ultra-high molecular polyethylene pipe is characterized by comprising the following steps:
heating and plasticizing the material in a plasticizing extrusion system;
extruding the plasticized material in the plasticizing extrusion system into a space between a core mold and a molding pipe mold of the molding system through an extrusion structure, wherein the molding pipe mold is sleeved outside the core mold; and
and providing a cooling temperature of 55-85 ℃ by a cooling device to simultaneously cool and shape the outer wall and the inner wall of the formed pipe, and forming the formed pipe between the formed pipe die and the core die.
9. The method of claim 8, wherein the extrusion structure forms an annular conical channel, the tip of the annular conical channel faces the plasticizing extrusion system, and the plasticized material is extruded into the molding system between a core mold and a molding pipe mold in a conical split manner through the annular conical channel.
10. The method for manufacturing ultra-high molecular polyethylene pipe according to claim 8, wherein the plasticizing extrusion system is sequentially divided into a feeding zone, a melting zone, a first homogenizing zone, a second homogenizing zone, a third homogenizing zone and a joint zone with different temperatures along the material advancing direction, and the heating temperature of the feeding zone is 215-220 ℃; the heating temperature of the melting zone is 220-225 ℃; the heating temperature of the first homogenizing zone is 225-230 ℃; the heating temperature of the second homogenizing zone is 230-235 ℃; the heating temperature of the third homogenizing zone is 235-240 ℃; the heating temperature of the joint area is 240-245 ℃; and/or the presence of a gas in the gas,
the extrusion structure is sequentially divided into a first temperature area and a second temperature area along the advancing direction of the material, wherein the temperature of the first temperature area is 240-245 ℃, and the temperature of the second temperature area is 235-240 ℃.
Technical Field
The invention relates to the field of engineering plastics, in particular to production equipment and a manufacturing method of an ultrahigh molecular polyethylene pipe.
Background
The UPE PIPE is an English abbreviation of an ultra-high molecular weight polyethylene PIPE (UHMW-PE PIPE), is fully called as an (ultra-high molecular weight polyethylene PIPE) and is formed by polymerizing ethylene and butadiene monomers under the action of a catalyst, and the thermoplastic engineering plastic with the average molecular weight of more than 200 ten thousand belongs to a new chemical material and a new product, and is the engineering plastic with the best comprehensive performance.
The existing ultrahigh molecular polyethylene pipe is manufactured by adopting an extrusion molding process, materials are added into an extruder, the materials are preheated by a heating device and friction outside a machine barrel under the extrusion pushing action, the materials are melted and plasticized under the conditions of high temperature and high pressure, then the melted materials are pushed into a machine head die, and the melted materials extruded from the machine head die are cooled and molded into the required ultrahigh molecular polyethylene product.
However, in the existing production technology, the ultra-high molecular weight polyethylene pipe has the problems of defective finished product surface, uneven wall thickness, unsmooth finish, even cracking and the like.
Disclosure of Invention
In view of the above, it is necessary to provide an apparatus and a method for producing an ultra-high molecular weight polyethylene pipe, which are directed to the problems that are easily caused by the production of the ultra-high molecular weight polyethylene pipe.
The production equipment of the ultra-high molecular polyethylene pipe comprises a plasticizing extrusion system, a hydraulic system, a forming system and a control system;
the molding system comprises a pipe mold and a cooling device;
the pipe mold comprises a main mold, a core mold and a forming pipe mold, the main mold is arranged at the front ends of the core mold and the forming pipe mold along the advancing direction of materials, the forming pipe mold is sleeved outside the core mold, and the main mold is used for enabling the materials extruded from the plasticizing extrusion system to flow into the space between the core mold and the forming pipe mold in a straight line; the forming pipe die is used for forming the outer wall of the ultrahigh molecular polyethylene pipe; the core mold is sleeved in the forming pipe mold and is used for forming the inner wall of the ultrahigh molecular polyethylene pipe;
the cooling device comprises a first cooling element and a second cooling element, the first cooling element is used for cooling the formed pipe die, the second cooling element is used for cooling the core die, and the cooling device provides a cooling temperature of 55-85 ℃ so that the formed pipe die and the core die can keep the same temperature.
In one embodiment, the plasticizing extrusion system comprises a barrel and a push rod, and the hydraulic system is used for driving the push rod to push the material plasticized in the barrel into the molding system.
In one embodiment, the core mold has a hollow inner cavity, and the second cooling element comprises a second cooling circulation line, and the hollow inner cavity is communicated with the second cooling circulation line and used for circulating a cooling medium through the hollow inner cavity to cool the core mold.
In one embodiment, the main mold comprises an outer mold sleeve and a spreader cone sleeved inside the outer mold sleeve, the tip of the spreader cone faces the plasticizing extrusion system, a channel for the material to flow is formed between the outer mold sleeve and the spreader cone, so that the material enters the space between the core mold and the forming pipe mold from the plasticizing extrusion system, and the taper of the spreader cone is 50-55 degrees.
In one embodiment, the plasticizing extrusion system is sequentially divided into a feeding area, a melting area, a first homogenizing area, a second homogenizing area, a third homogenizing area and a joint area, wherein the feeding area is heated to 215-220 ℃; the heating temperature of the melting zone is 220-225 ℃; the heating temperature of the first homogenizing zone is 225-230 ℃; the heating temperature of the second homogenizing zone is 230-235 ℃; the heating temperature of the third homogenizing zone is 235-240 ℃; the heating temperature of the joint area is 240-245 ℃.
In one embodiment, the main mold is sequentially divided into a first temperature area and a second temperature area along the material advancing direction, wherein the temperature of the first temperature area is 240-245 ℃, and the temperature of the second temperature area is 235-240 ℃.
A manufacturing method of the ultra-high molecular polyethylene pipe by using the production equipment of the ultra-high molecular polyethylene pipe comprises the following steps:
plasticizing a material by heating of the plasticizing extrusion system and extruding the plasticized material into the molding system; and
and the plasticized material enters the core mold and the forming pipe mold through the main mold for forming, and the outer wall and the inner wall of the formed pipe are simultaneously cooled and shaped through the cooling device.
A manufacturing method of an ultrahigh molecular polyethylene pipe comprises the following steps:
heating and plasticizing the material in a plasticizing extrusion system;
extruding the plasticized material in the plasticizing extrusion system into a space between a core mold and a molding pipe mold of the molding system through an extrusion structure, wherein the molding pipe mold is sleeved outside the core mold; and
and providing a cooling temperature of 55-85 ℃ by a cooling device to simultaneously cool and shape the outer wall and the inner wall of the formed pipe, and forming the formed pipe between the formed pipe die and the core die.
In one embodiment, the extrusion structure forms an annular conical channel, the tip of the annular conical channel faces the plasticizing extrusion system, and the plasticized material is extruded into a space between a core mold and a forming pipe mold of the forming system in a conical split manner through the annular conical channel.
In one embodiment, the taper of the conical shunt is 50-55 degrees.
In one embodiment, the plasticizing extrusion system is sequentially divided into a feeding area, a melting area, a first homogenizing area, a second homogenizing area, a third homogenizing area and a joint area, wherein the feeding area is heated to 215-220 ℃; the heating temperature of the melting zone is 220-225 ℃; the heating temperature of the first homogenizing zone is 225-230 ℃; the heating temperature of the second homogenizing zone is 230-235 ℃; the heating temperature of the third homogenizing zone is 235-240 ℃; the heating temperature of the joint area is 240-245 ℃.
In one embodiment, the extrusion structure is sequentially divided into a first temperature zone and a second temperature zone along the material advancing direction, wherein the temperature of the first temperature zone is 240-245 ℃, and the temperature of the second temperature zone is 235-240 ℃.
The invention provides ultrahigh molecular polyethylene pipe production equipment which comprises a molding system, wherein the molding system comprises a pipe mold and a cooling device. The pipe mold comprises a main mold, a core mold and a forming pipe mold. The core mould is used for forming the inner wall of the ultra-high molecular polyethylene pipe, the forming pipe mould is used for forming the outer wall of the ultra-high molecular polyethylene pipe, and the cooling device provides a cooling temperature of 55-85 ℃ so that the forming pipe mould and the core mould are kept at the same temperature.
The shaping pipe die the mandrel with under cooling device's the mutually supporting, the ultra high molecular polyethylene material is when the shaping is tubular product, the shaping pipe die with the mandrel homoenergetic makes the material cooling between them, improves the inside and outside homogeneity of temperature of tubular product, effectively avoids finished product ultra high molecular polyethylene tubular product surface, especially the defect of inner wall, wall thickness inhomogeneous, the surface is not smooth or even the scheduling problem that ftractures, makes the ultra high molecular polyethylene tubular product yield of production improve greatly when improving production efficiency. This application realizes extruding of ultra high molecular polyethylene material through hydraulic system, and hydraulic system can provide bigger driving force, more is suitable for the promotion of the relatively poor ultra high molecular polyethylene's of mobility material.
Drawings
FIG. 1 is a schematic structural diagram of an apparatus for producing an ultra-high molecular weight polyethylene pipe according to an embodiment of the present invention;
FIG. 2 is a schematic structural view of a pipe mold and a cooling device according to an embodiment of the present invention;
fig. 3 is a schematic view of a core mold structure according to an embodiment of the present invention.
10-a motor;
20-oil cylinder;
30-a hopper;
40-a barrel;
50-a control system;
60-a push rod;
70-flange joint;
80-material nozzle;
100-pipe mould;
120-a main mold;
122-outer die sleeve; 124-a splitter cone;
140-core mold;
142-a hollow lumen; 144-a separator; 146-a closed chamber;
160-forming a tube mold;
162-a cooling jacket;
200-a cooling device;
210-a first cooling circulation line; 230-second cooling circulation line.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail by the following embodiments, which are taken in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Referring to fig. 1, an embodiment of the present invention provides an apparatus for producing an ultra-high molecular weight polyethylene pipe, including a plasticizing extrusion system, a hydraulic system, a molding system, and a control system.
The plasticizing extrusion system comprises a material barrel 40 and a push rod 60 arranged in the material barrel 40, and the hydraulic system is used for driving the push rod to push the plasticized materials in the material barrel 40 into the molding system.
The molding system includes a tube mold 100 and a
The pipe mold 100 includes a
The
The ultrahigh molecular polyethylene pipe production equipment provided by the embodiment of the invention comprises a forming system, wherein the forming system comprises a pipe mould and a cooling device, the pipe mould comprises a main mould, a core mould and a forming pipe mould, the core mould is used for forming the inner wall of the ultrahigh molecular polyethylene pipe, the forming pipe mould is used for forming the outer wall of the ultrahigh molecular polyethylene pipe, and the
The ultra-high molecular polyethylene pipe production apparatus further includes a heating device (not shown in the drawings) for heating the plasticizing extrusion system and the
In order to improve the yield of the ultra-high molecular polyethylene pipe, along the advancing direction of the material, the plasticizing extrusion system can be sequentially divided into six different temperature heating sections of a feeding area, a melting area, a first homogenizing area, a second homogenizing area, a third homogenizing area and a joint area according to the heating temperature of a heating device to different positions of the heating device. In one embodiment, the feeding zone is from 1/4 to 1/3 sections of the charging barrel 40, the melting zone is from 1/4 to 1/3 sections of the charging barrel 40, the homogenizing zone is from 1/4 to 1/3 sections of the charging barrel 40, and the homogenizing zones are respectively a first homogenizing zone, a second homogenizing zone and a third homogenizing zone according to different temperatures along the advancing direction of the materials. There is a spacing of the same or different distances between two adjacent segments, and the joint region is the connecting portion of barrel 40 and
In an embodiment, the ultrahigh molecular polyethylene pipe production equipment further comprises a feeding device, the feeding device is arranged corresponding to a feeding area of the plasticizing extrusion system, the feeding device comprises a hopper 30, the feeding device feeds materials into the production equipment through the hopper 30, the fed ultrahigh molecular polyethylene raw materials enter a charging barrel 40 of the feeding area of the plasticizing extrusion system, and the plasticizing extrusion is performed under the cooperation of a hydraulic system and a push rod 60.
The hydraulic system can comprise a motor 10, an oil cylinder 20 and the like, wherein the motor 10, the oil cylinder 20 and the push rod 60 are sequentially connected to convert hydraulic energy into kinetic energy and realize the reciprocating linear motion of the push rod.
The
The inner cavity of the
To facilitate removal and replacement of the
Referring to fig. 2, in one embodiment, the
In one embodiment, the outer wall of the forming
The temperatures of the cooling mediums introduced into the first
In one embodiment, the first cooling element and the second cooling element are used to maintain the same temperature of the molded
In one embodiment, the cooling medium introduced into the first
The first
Referring to fig. 3, a partition 144 is disposed in the hollow
The wall thickness of the ultra-high molecular polyethylene pipe and the length of the cooling section have a certain proportional relation. Preferably, the length of the
Further, the too long length of the forming pipe die 160 may also cause back pressure to be generated in the extrusion process of the ultra-high molecular polyethylene pipe, resulting in scratches, strain, black spots and other problems on the surface of the finished product. Preferably, the length of the forming pipe die 160 is L, the inner diameter of the forming pipe die 160 is R, the outer diameter of the core die 140 is R, and L (R-R)/2 is 20: 1-3: 4.
In addition, the smoothness of the outer wall of the
Referring to fig. 1, the manufacturing apparatus includes a drawing device 300 along the material advancing direction, the drawing device 300 is disposed behind the forming
Draw gear 300 includes transmission, roller closing device and brake gear, adjusts the elasticity degree that roller closing device pressed from both sides tight tubular product through brake gear, increases frictional force, for not stereotyping the fuse-element provides pressure, makes tubular product structure inseparabler, adjusts the wall thickness and the eccentricity of tubular product simultaneously and reduces the external diameter tolerance of tubular product.
The ultra-high molecular polyethylene pipe production equipment further comprises a cutting device 400, wherein the cutting device 400 is installed behind the outlet of the traction device 300 and is used for cutting the ultra-high molecular polyethylene pipe into sections. The cutting device is preferably a band sawing machine, wheels and rails are welded at the bottom of the band sawing machine, the cutting device can extrude and cut while not clamping bent saw blades in the production process, and two ends of the surface of a cut pipe finished product are smoother.
The control system 50 includes electrical instruments and actuators for automatically controlling the speed of movement of the ram 60 and the temperature, pressure, flow rate and product quality of the entire manufacturing facility during the manufacturing process.
The embodiment of the invention also provides a manufacturing method of the ultrahigh molecular weight polyethylene pipe, which comprises the following steps:
s20, heating and plasticizing the material in a plasticizing extrusion system;
s40, extruding the plasticized material in the plasticizing extrusion system into a space between a core mold and a forming pipe mold of the forming system through an extrusion structure, wherein the forming pipe mold is sleeved outside the core mold; and
and S60, providing a cooling temperature of 55-85 ℃ through a cooling device to simultaneously cool and shape the outer wall and the inner wall of the formed pipe, and forming the formed pipe between the formed pipe die and the core die.
The embodiment of the method for manufacturing the ultra-high molecular weight polyethylene pipe can be implemented by adopting the production equipment of the ultra-high molecular weight polyethylene pipe in any one of the above embodiments, and also can be implemented by adopting other production equipment capable of realizing the method.
In an embodiment, in step S20, in the step of plasticizing the material by heating of the plasticizing extrusion system, the plasticizing extrusion system may be divided into six zones for heating. Specifically, along the advancing direction of the material, the plasticizing extrusion system is sequentially divided into a feeding area, a melting area, a first homogenizing area, a second homogenizing area, a third homogenizing area and a joint area, wherein the feeding area, the melting area, the first homogenizing area, the second homogenizing area, the third homogenizing area and the joint area are different in temperature. In one embodiment, the heating temperature of the feed zone is 215 ℃ to 220 ℃; the heating temperature of the melting zone is 220-225 ℃; the heating temperature of the first homogenizing zone is 225-230 ℃; the heating temperature of the second homogenizing zone is 230-235 ℃; the heating temperature of the third homogenizing zone is 235-240 ℃; the heating temperature of the joint area is 240-245 ℃.
In one embodiment, the step of extruding the plasticized material into the molding system includes starting the motor 10 to drive the push rod 60 to reciprocate linearly, and extruding the plasticized material by the push rod 60.
In an embodiment, the extrusion structure may be a main mold in the above ultra-high molecular polyethylene pipe production equipment, step S40. The step of extruding the plasticized material in the plasticizing extrusion system into a space between a core mold and a forming pipe mold of the forming system through the extrusion structure further comprises the step of heating the extrusion structure at constant temperature in two zones to ensure that the material is formed at a certain viscosity. Specifically, along the direction that the material gos forward, the extrusion structure divide into first temperature zone and second temperature zone in proper order. In one embodiment, the first temperature zone is 240 ℃ to 245 ℃ and the second temperature zone is 235 ℃ to 240 ℃.
In one embodiment, the extrusion structure forms an annular conical channel, the tip of the annular conical channel faces the plasticizing extrusion system, and the plasticized material is extruded into a position between a core mold and a forming pipe mold of the forming system in a conical split flow mode through the annular conical channel. In one embodiment, the taper of the conical shunt may be 50 degrees to 55 degrees. For example, the main mold as the extrusion structure comprises an outer mold sleeve and a diverging cone sleeved inside the outer mold sleeve, and the annular tapered channel is formed between the outer mold sleeve and the diverging cone.
In the step S60, the cooling temperature of 55-85 ℃ is provided by a cooling device, so that the outer wall and the inner wall of the formed pipe are simultaneously cooled and shaped, and the temperature of the cooling medium in the cooling device is 55-85 ℃.
Preferably, the outer wall and the inner wall of the formed pipe are cooled and shaped at the same speed by controlling the temperature of the first cooling element and the second cooling element.
The manufacturing method further includes step S70 and step S80:
s80, pulling the pipe out of the forming die through the pulling force of the pulling device, adjusting the brake block to clamp the pipe, and adjusting the tolerance of the outer diameter of the pipe; and
and S90, measuring the length by using a caliper, and starting the cutting device to cut the pipe.
In the step S70, the magnitude of the traction pulling force is 594N-810N; the step of enabling the structure of the extruded finished product to be compact and adjusting the outer diameter tolerance of the pipe simultaneously comprises the steps of clamping the pipe by adjusting the tightness of a brake strip of a brake seat, and reducing the outer diameter tolerance of the pipe by adjusting the wall thickness and the eccentricity of the pipe by adjusting the tightness of a brake.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
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