An injection molding process for a bearing sleeve of a logistics conveyor belt

Abstract

The invention provides an injection molding process for a logistics conveyor belt bearing sleeve, comprising the following steps: S1, mixing solid lubricants, nanoparticles and polytetrafluoroethylene particles and adding them into a primary injection molding machine for melting; S2, mixing carbon fibers, PI polyimide plastic particles and solid lubricants and adding them into a secondary injection molding machine for melting; S3, preheating the mold temperature to 160-200°C, with a preheating time of 30-90 minutes; the invention uses nanoparticles to perform mixed modification on polytetrafluoroethylene particles, so as to improve the strength and high temperature resistance of an inner skeleton of a bearing sleeve, and then uses PI polyimide plastic to perform secondary injection molding on the basis of the inner skeleton of the bearing sleeve, so as to fill the PI polyimide plastic on the outer side of the inner skeleton of the bearing sleeve, so as to improve the overall wear resistance and corrosion resistance of the logistics conveyor belt bearing sleeve, avoid the phenomenon that the bearing sleeve is prone to corrosion and high temperature deformation, and improve the service life of the logistics conveyor belt bearing sleeve.

Description

Technical Field

[0001] The invention relates to an injection molding process, in particular to an injection molding process for a logistics conveyor belt bearing sleeve, and belongs to the technical field of plastic bearing production. Background Art

[0002] Bearing is an important component in contemporary mechanical equipment. Its main function is to support the mechanical rotating body, reduce the friction coefficient during its movement, and ensure its rotation accuracy. Plastic bearing is a kind of bearing. The plastic bearings used can generally be divided into plastic rolling bearings and plastic sliding bearings. The working principles of plastic rolling bearings and plastic sliding bearings can be distinguished by their names. The friction generated when plastic rolling bearings are working is rolling friction, while the friction generated when plastic sliding bearings are working is sliding friction. The magnitude of rolling friction mainly depends on the manufacturing accuracy; while the magnitude of friction of plastic sliding bearings mainly depends on the material of the bearing sliding surface. Plastic bearings are generally made of engineering plastics with relatively good performance and have self-lubricating function. Plastic bearings are one of the important components in logistics conveying equipment, mainly used to reduce the friction coefficient of the relevant structures of logistics conveying equipment during movement.

[0003] Traditional logistics conveyor belt bearing sleeves are usually produced by injection molding using only a single engineering plastic as raw material, resulting in the bearing sleeves having relatively simple characteristics, and their corrosion resistance and high temperature resistance are usually poor, which leads to the logistics conveyor belt bearing sleeves being prone to corrosion and high temperature deformation after long-term use. Therefore, an injection molding process for logistics conveyor belt bearing sleeves is proposed. Summary of the invention

[0004] In view of this, the present invention hopes to provide a logistics conveyor belt bearing sleeve injection molding process to solve or alleviate the technical problems existing in the prior art, or at least provide a beneficial choice.

[0005] The technical solution of the embodiment of the present invention is implemented as follows: A logistics conveyor belt bearing sleeve injection molding process comprises the following steps:

[0006] S1, mixing solid lubricant, nanoparticles and polytetrafluoroethylene particles and adding them into an injection molding machine to melt the material;

[0007] S2, mixing carbon fiber, PI polyimide plastic particles and solid lubricant and adding them into a secondary injection molding machine to melt the material;

[0008] S3. Preheat the mold temperature to 160-200°C for 30-90 minutes;

[0009] S4, close the mold with the primary mold, and then inject the mixed melt into the mold through the primary injection molding machine, and the filling time is 0.2-0.8s;

[0010] S5. After cooling is completed, the mold and the primary mold are separated to obtain the inner frame of the bearing sleeve;

[0011] S6. Move the mold and the inner frame of the bearing sleeve to the secondary mold through a turntable, and move the unused mold to the primary mold;

[0012] S7, closing the mold with the secondary mold, and then injecting the mixed melt into the mold through the secondary injection molding machine, with a filling time of 0.5-1s, so as to coat the corrosion-resistant material outside the inner frame of the bearing sleeve;

[0013] S8. After the mold and the secondary mold are cooled, the mold is separated, and then the cooled and formed bearing sleeve is ejected through the demoulding mechanism to complete the injection molding process.

[0014] Further preferably, in S1, the melt temperature of the primary injection molding machine is 380-420° C., and the melt time is 2-3 hours.

[0015] Further preferably, in S1, the nanoparticles are aluminum oxide, silicon dioxide or titanium dioxide, which are modified by mixing with tetrafluoroethylene to improve the strength and friction resistance of the inner skeleton of the bearing sleeve.

[0016] Further preferably, in S2, the melt temperature of the secondary injection molding machine is 400-460°C, and the melt time is 2-4h.

[0017] Further preferably, in S2, carbon fiber is mixed with PI polyimide to suppress the wear of PI polyimide plastic and improve the wear resistance of PI polyimide plastic. Moreover, PI polyimide plastic has good chemical stability and high corrosion resistance.

[0018] Further preferably, in S3, since the bearing sleeve materials are all high temperature resistant materials and the melt temperature is high, the mold can be preheated to effectively improve the use efficiency of the mold and avoid damage to the mold due to a large temperature difference.

[0019] Further preferably, in S4, the holding time of the primary injection molding machine and the mold is 15-20s, and the holding pressure is 100-140Mpa.

[0020] Further preferably, in S5, the cooling time is 10-20s, the cooling method is circulating water cooling, and the temperature after cooling is 140-180°C.

[0021] Further preferably, in S6, the two sets of molds are driven by a turntable to exchange positions so as to perform continuous injection molding production on the bearing sleeve.

[0022] Further preferably, in S8, the cooling time is 20-30s, the cooling method is circulating water cooling, and the temperature after cooling is 30-60°C.

[0023] Since the embodiment of the present invention adopts the above technical scheme, it has the following advantages: the present invention uses nanoparticles to mix and modify polytetrafluoroethylene particles to improve the strength and high temperature resistance of the inner skeleton of the bearing sleeve, and then uses PI polyimide plastic for secondary injection molding on the basis of the inner skeleton of the bearing sleeve to fill the PI polyimide plastic on the outside of the inner skeleton of the bearing sleeve to improve the overall wear resistance and corrosion resistance of the logistics conveyor belt bearing sleeve, avoid the phenomenon that the bearing sleeve is prone to corrosion and high temperature deformation, and improve the service life of the logistics conveyor belt bearing sleeve.

[0024] The above summary is for illustrative purposes only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments and features described above, further aspects, embodiments and features of the present invention will be readily apparent by reference to the accompanying drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 It is a flow chart of the steps of the present invention. DETAILED DESCRIPTION

[0027] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the present invention. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.

[0028] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0029] Embodiment 1

[0030] like Figure 1 As shown, an embodiment of the present invention provides an injection molding process for a logistics conveyor belt bearing sleeve, comprising the following steps:

[0031] S1, mixing solid lubricant, nanoparticles and polytetrafluoroethylene particles and adding them into an injection molding machine to melt the material;

[0032] S2, mixing carbon fiber, PI polyimide plastic particles and solid lubricant and adding them into a secondary injection molding machine to melt the material;

[0033] S3, preheat the mold temperature to 160°C, the preheating time is 30 minutes;

[0034] S4, the mold and the primary mold are closed, and then the mixed melt is injected into the mold by the primary injection molding machine, and the filling time is 0.2s;

[0035] S5. After cooling is completed, the mold and the primary mold are separated to obtain the inner frame of the bearing sleeve;

[0036] S6. Move the mold and the inner frame of the bearing sleeve to the secondary mold through a turntable, and move the unused mold to the primary mold;

[0037] S7, closing the mold with the secondary mold, and then injecting the mixed melt into the mold through the secondary injection molding machine, with a filling time of 0.5s, so as to coat the corrosion-resistant material outside the inner frame of the bearing sleeve;

[0038] S8. After the mold and the secondary mold are cooled, the mold is separated, and then the cooled and formed bearing sleeve is ejected through the demoulding mechanism to complete the injection molding process.

[0039] In one embodiment, in S1, the melt temperature of the primary injection molding machine is 380° C., and the melt time is 2 hours.

[0040] In one embodiment, in S1, the nanoparticles are aluminum oxide, silicon dioxide or titanium dioxide, which are modified by mixing with tetrafluoroethylene to improve the strength and friction resistance of the inner skeleton of the bearing sleeve; tetrafluoroethylene is mixed and modified with nanoparticles to improve the strength and friction resistance of the inner skeleton of the bearing sleeve.

[0041] In one embodiment, in S2, the melt temperature of the secondary injection molding machine is 400° C., and the melt time is 2 hours.

[0042] In one embodiment, in S2, carbon fiber is mixed with PI polyimide to suppress the wear of PI polyimide plastic and improve the wear resistance of PI polyimide plastic. PI polyimide plastic has good chemical stability and high corrosion resistance. Carbon fiber is used to mix and modify PI polyimide plastic to improve the wear resistance of PI polyimide plastic.

[0043] In one embodiment, in S3, since the bearing sleeve materials are all high temperature resistant materials and the melt temperature is high, the mold can be preheated to effectively improve the use efficiency of the mold and avoid damage to the mold due to excessive temperature difference.

[0044] In one embodiment, in S4, the holding time of the injection molding machine and the mold is 15s, and the holding pressure is 100Mpa; the shrinkage rate and warping deformation of the bearing sleeve are reduced by controlling the holding time and the holding temperature.

[0045] In one embodiment, in S5, the cooling time is 10s, the cooling method is circulating water cooling, and the temperature after cooling is 180°C; the inner skeleton of the bearing sleeve is quickly cooled and shaped by cooling the mold with water.

[0046] In one embodiment, in S6, the two sets of molds are driven by a turntable to interchange positions so as to perform continuous injection molding production on the bearing sleeve; the two sets of molds are used to simultaneously close the mold with the primary mold and the secondary mold respectively so as to perform primary and secondary injection molding simultaneously.

[0047] In one embodiment, in S8, the cooling time is 20 seconds, the cooling method is circulating water cooling, and the temperature after cooling is 60° C.; the bearing sleeve is quickly cooled and shaped by cooling the mold with water.

[0048] Embodiment 2

[0049] like Figure 1 As shown, an embodiment of the present invention provides an injection molding process for a logistics conveyor belt bearing sleeve, comprising the following steps:

[0050] S1, mixing solid lubricant, nanoparticles and polytetrafluoroethylene particles and adding them into an injection molding machine to melt the material;

[0051] S2, mixing carbon fiber, PI polyimide plastic particles and solid lubricant and adding them into a secondary injection molding machine to melt the material;

[0052] S3, preheat the mold temperature to 180°C, the preheating time is 60 minutes;

[0053] S4, the mold and the primary mold are closed, and then the mixed melt is injected into the mold by the primary injection molding machine, and the filling time is 0.5s;

[0054] S5. After cooling is completed, the mold and the primary mold are separated to obtain the inner frame of the bearing sleeve;

[0055] S6. Move the mold and the inner frame of the bearing sleeve to the secondary mold through a turntable, and move the unused mold to the primary mold;

[0056] S7, closing the mold with the secondary mold, and then injecting the mixed melt into the mold through the secondary injection molding machine, with a filling time of 0.7s, so as to coat the corrosion-resistant material outside the inner frame of the bearing sleeve;

[0057] S8. After the mold and the secondary mold are cooled, the mold is separated, and then the cooled and formed bearing sleeve is ejected through the demoulding mechanism to complete the injection molding process.

[0058] In one embodiment, in S1, the melt temperature of the primary injection molding machine is 400° C., and the melt time is 2.5 hours.

[0059] In one embodiment, in S1, the nanoparticles are aluminum oxide, silicon dioxide or titanium dioxide, which are modified by mixing with tetrafluoroethylene to improve the strength and friction resistance of the inner skeleton of the bearing sleeve; tetrafluoroethylene is mixed and modified with nanoparticles to improve the strength and friction resistance of the inner skeleton of the bearing sleeve.

[0060] In one embodiment, in S2, the melt temperature of the secondary injection molding machine is 430° C., and the melt time is 3 hours.

[0061] In one embodiment, in S2, carbon fiber is mixed with PI polyimide to suppress the wear of PI polyimide plastic and improve the wear resistance of PI polyimide plastic. PI polyimide plastic has good chemical stability and high corrosion resistance. Carbon fiber is used to mix and modify PI polyimide plastic to improve the wear resistance of PI polyimide plastic.

[0062] In one embodiment, in S3, since the bearing sleeve materials are all high temperature resistant materials and the melt temperature is high, the mold can be preheated to effectively improve the use efficiency of the mold and avoid damage to the mold due to excessive temperature difference.

[0063] In one embodiment, in S4, the holding time of the injection molding machine and the mold is 18s, and the holding pressure is 120Mpa; the holding time and the holding temperature are controlled to reduce the shrinkage rate and warping deformation of the bearing sleeve.

[0064] In one embodiment, in S5, the cooling time is 15s, the cooling method is circulating water cooling, and the temperature after cooling is 160°C; the inner skeleton of the bearing sleeve is quickly cooled and shaped by cooling the mold with water.

[0065] In one embodiment, in S6, the two sets of molds are driven by a turntable to interchange positions so as to perform continuous injection molding production on the bearing sleeve; the two sets of molds are used to simultaneously close the mold with the primary mold and the secondary mold respectively so as to perform primary and secondary injection molding simultaneously.

[0066] In one embodiment, in S8, the cooling time is 25 seconds, the cooling method is circulating water cooling, and the temperature after cooling is 40° C.; the bearing sleeve is quickly cooled and shaped by cooling the mold with water.

[0067] Embodiment 3

[0068] like Figure 1 As shown, an embodiment of the present invention provides an injection molding process for a logistics conveyor belt bearing sleeve, comprising the following steps:

[0069] S1, mixing solid lubricant, nanoparticles and polytetrafluoroethylene particles and adding them into an injection molding machine to melt the material;

[0070] S2, mixing carbon fiber, PI polyimide plastic particles and solid lubricant and adding them into a secondary injection molding machine to melt the material;

[0071] S3, preheat the mold temperature to 200°C, the preheating time is 90 minutes;

[0072] S4, the mold and the primary mold are closed, and then the mixed melt is injected into the mold by the primary injection molding machine, and the filling time is 0.8s;

[0073] S5. After cooling is completed, the mold and the primary mold are separated to obtain the inner frame of the bearing sleeve;

[0074] S6. Move the mold and the inner frame of the bearing sleeve to the secondary mold through a turntable, and move the unused mold to the primary mold;

[0075] S7, closing the mold with the secondary mold, and then injecting the mixed melt into the mold through the secondary injection molding machine, with a filling time of 1 second, so as to coat the corrosion-resistant material outside the inner frame of the bearing sleeve;

[0076] S8. After the mold and the secondary mold are cooled, the mold is separated, and then the cooled and formed bearing sleeve is ejected through the demoulding mechanism to complete the injection molding process.

[0077] In one embodiment, in S1, the melt temperature of the primary injection molding machine is 420° C., and the melt time is 3 hours.

[0078] In one embodiment, in S1, the nanoparticles are aluminum oxide, silicon dioxide or titanium dioxide, which are modified by mixing with tetrafluoroethylene to improve the strength and friction resistance of the inner skeleton of the bearing sleeve; tetrafluoroethylene is mixed and modified with nanoparticles to improve the strength and friction resistance of the inner skeleton of the bearing sleeve.

[0079] In one embodiment, in S2, the melt temperature of the secondary injection molding machine is 460° C., and the melt time is 4 hours.

[0080] In one embodiment, in S2, carbon fiber is mixed with PI polyimide to suppress the wear of PI polyimide plastic and improve the wear resistance of PI polyimide plastic. PI polyimide plastic has good chemical stability and high corrosion resistance. Carbon fiber is used to mix and modify PI polyimide plastic to improve the wear resistance of PI polyimide plastic.

[0081] In one embodiment, in S3, since the bearing sleeve materials are all high temperature resistant materials and the melt temperature is high, the mold can be preheated to effectively improve the use efficiency of the mold and avoid damage to the mold due to excessive temperature difference.

[0082] In one embodiment, in S4, the holding time of the injection molding machine and the mold is 20s, and the holding pressure is 140Mpa; the holding time and the holding temperature are controlled to reduce the shrinkage rate and warping deformation of the bearing sleeve.

[0083] In one embodiment, in S5, the cooling time is 20s, the cooling method is circulating water cooling, and the temperature after cooling is 140°C; the inner skeleton of the bearing sleeve is quickly cooled and shaped by cooling the mold with water.

[0084] In one embodiment, in S6, the two sets of molds are driven by a turntable to interchange positions so as to perform continuous injection molding production on the bearing sleeve; the two sets of molds are used to simultaneously close the mold with the primary mold and the secondary mold respectively so as to perform primary and secondary injection molding simultaneously.

[0085] In one embodiment, in S8, the cooling time is 30 seconds, the cooling method is circulating water cooling, and the temperature after cooling is 30° C. The bearing sleeve is quickly cooled and shaped by cooling the mold with water.

[0086] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of various changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A logistics conveyor belt bearing sleeve injection molding process, characterized in that: The following steps are involved: S1, mixing solid lubricant, nanoparticles and polytetrafluoroethylene particles and adding them into an injection molding machine to melt the material; S2, mixing carbon fiber, PI polyimide plastic particles and solid lubricant and adding them into a secondary injection molding machine to melt the material; S3. Preheat the mold temperature to 160-200°C for 30-90 minutes; S4, close the mold and the primary mold, and then inject the mixed melt into the mold through the primary injection molding machine, and the filling time is 0.2-0.8s; S5. After cooling is completed, the mold and the primary mold are separated to obtain the inner frame of the bearing sleeve; S6. Move the mold and the inner frame of the bearing sleeve to the secondary mold through a turntable, and move the unused mold to the primary mold; S7, closing the mold with the secondary mold, and then injecting the mixed melt into the mold through the secondary injection molding machine, with a filling time of 0.5-1s, so as to coat the corrosion-resistant material outside the inner frame of the bearing sleeve; S8, after the mold and the secondary mold are cooled, the mold is separated, and then the cooled and formed bearing sleeve is ejected by the demoulding mechanism to complete the injection molding process; The melt temperature of the primary injection molding machine is 380-420°C, the melt time is 2-3h, the nanoparticles are alumina, silica or titanium dioxide, which are modified by mixing with polytetrafluoroethylene, and the melt temperature of the secondary injection molding machine is 400-460°C, the melt time is 2-4h.

2. The injection molding process of a logistics conveyor belt bearing sleeve according to claim 1, characterized in that: In S2, carbon fiber is mixed with PI polyimide to suppress the wear of PI polyimide plastic and improve the wear resistance of PI polyimide plastic. PI polyimide plastic has good chemical stability and high corrosion resistance.

3. The injection molding process of a logistics conveyor belt bearing sleeve according to claim 1, characterized in that: In S3, since the bearing sleeve materials are all high temperature resistant materials and the melt temperature is high, the mold is preheated.

4. The injection molding process for a logistics conveyor belt bearing sleeve according to claim 1, characterized in that: In S4, the holding time of the primary injection molding machine and the mold is 15-20s, and the holding pressure is 100-140Mpa.

5. The injection molding process of a logistics conveyor belt bearing sleeve according to claim 1, characterized in that: In S5, the cooling time is 10-20s, the cooling method is circulating water cooling, and the temperature after cooling is 140-180°C.

6. The injection molding process for a logistics conveyor belt bearing sleeve according to claim 1, characterized in that: In S6, the two sets of molds are driven by the turntable to exchange positions so as to perform continuous injection molding production on the bearing sleeve.

7. The injection molding process for a logistics conveyor belt bearing sleeve according to claim 1, characterized in that: In S8, the cooling time is 20-30s, the cooling method is circulating water cooling, and the temperature after cooling is 30-60°C.

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