A dynamic mold locking and dynamic mold temperature collaborative injection molding process

Abstract

The application relates to a dynamic mold locking and dynamic mold temperature collaborative injection molding process, which comprises the following steps: S1: setting a target holding pressure of injection molding, a high-temperature section and a low-temperature section temperature of dynamic mold temperature, an injection molding cycle and a molding starting template value; S2: online correction is carried out according to real-time pressure and temperature of injection resin melt, so as to ensure that the melt pressure is constant; S3: the injection molding mold is closed in place, and the product is taken out after the temperature is cooled to room temperature. Compared with the prior art, the application is developed based on current intelligent control technology, realizes dynamic mold locking and dynamic mold temperature collaboration on the basis of traditional injection molding, simultaneously considers green, environmental protection and low energy consumption, and has good industrialization development prospects.

Description

TECHNICAL FIELD

[0001] The application relates to the field of polymer physics forming technology, in particular to a dynamic clamping and dynamic mold temperature coordinated injection molding process. BACKGROUND

[0002] The main influencing factor in the melt filling process of injection molding is the influence of shear stress on the melt, which mainly influences the melt filling rate, product surface quality, mechanical properties and microstructure of the material, and under the condition of certain injection molding parameters, the mold surface temperature becomes an important influencing factor, which is related to the melt shear stress, thermodynamic properties of the melt, forming efficiency and micro-distribution of molecular chains.

[0003] Injection molding is a shear deformation at the interface of the polymer on the mold surface, and the cooling crystallization and molecular chain orientation of the material during the injection molding process are related to the macroscopic mechanical properties of the product. In the polymer rheology, the polyethylene melt is a non-Newtonian fluid, and the viscosity of the plastic has the characteristics of shear thinning, and the shear stress increases with the increase of the shear rate.

[0004] The temperature of the injection mold has a great influence on the mold filling flow of the plastic melt, solidification, production efficiency, and the shape and dimensional accuracy of the plastic part. For each plastic injection molding, there is a reasonable mold temperature range, which makes the melt flow well, easily fills the cavity, and the plastic part has small shrinkage and warping deformation after demolding, stable size, high mechanical properties and surface quality.

[0005] In order to control the temperature of the mold, a temperature regulating system must be designed, generally using mold cooling or heating methods, sometimes both. The temperature of the injection mold has a great influence on the mold filling flow of the plastic melt, solidification, production efficiency, and the shape and dimensional accuracy of the plastic part. For each plastic injection molding, there is a reasonable mold temperature range, which makes the melt flow well, easily fills the cavity, and the plastic part has small shrinkage and warping deformation after demolding, stable size, high mechanical properties and surface quality. For high melt viscosity resins such as UHMWPE, due to its extremely high molecular weight, the melt viscosity is very large, so under the condition of high shear rate of injection molding, the injection product is prone to shear rupture, which reduces the surface quality and mechanical properties of the product. The influence of injection molding mold temperature on the macroscopic performance of the product is as follows:

[0006] (1) Low mold temperature: the resin melt contacts the mold surface and cools rapidly, and due to the extremely high viscosity of the resin melt, the surface cooling layer of the product is prone to melt rupture and micro-phase separation in the inner melt layer, and is prone to melt shrinkage;

[0007] (2) Mold temperature is high: the resin melt contacts the mold surface and cools slowly, the temperature of the surface layer rises, the viscosity decreases, the shear stress decreases accordingly, the surface quality of the product improves, the inner melt is uniform, but the molding cycle of the product is long, and surface shrinkage is prone to occur;

[0008] (3) Mold temperature is higher than the melting point: since the mold temperature is higher than the melting point, the resin melt is still in a molten state after contacting the mold, so the product is no longer surface-cooled, and the product is completely uniform, but since there is no cooling, the resin product will deform and shrink after demolding, and needs to be re-sized. During the re-sizing process, since there is no high holding pressure, the surface quality of the product cannot be optimized;

[0009] (4) Cooling rate of mold temperature: different cooling rates of resin will result in different surface crystalline morphologies of the product. By optimizing the cooling rate, the mechanical properties can be optimized.

[0010] In recent years, dynamic mold temperature control technology has been developed for mold temperature control during injection molding. However, the current dynamic mold temperature control technology mainly focuses on passive temperature control, and does not link with the cooling and crystallization of resin and micro-distribution. Only the production efficiency is optimized. SUMMARY

[0011] The purpose of the present application is to overcome the defects of the prior art and provide a dynamic locking and dynamic mold temperature collaborative injection molding process. Based on the current intelligent control technology, dynamic locking and dynamic mold temperature collaboration are realized on the basis of traditional injection molding, while taking into account green, environmental protection and low energy consumption, and having good industrialization development prospects.

[0012] The purpose of the present application can be achieved by the following technical solutions:

[0013] The present application provides a dynamic locking and dynamic mold temperature collaborative injection molding process, comprising the following steps:

[0014] S1: setting the target holding pressure of injection molding, the high temperature section and the low temperature section temperature of dynamic mold temperature, the injection molding cycle, and the molding start template value;

[0015] S2: correcting online according to the real-time pressure and temperature of the injection resin melt, so as to ensure that the melt pressure is constant;

[0016] S3: closing the injection molding mold to the right place, waiting for the temperature to cool to room temperature, and opening the mold to take out the product.

[0017] Further, in S1, the target holding pressure of injection molding is obtained in the following manner:

[0018] According to the input product area and the maximum clamping force of the injection molding machine, the maximum pressure limit (clamping force / product area) is calculated, and a pressure value less than the maximum pressure limit is selected as the target holding pressure.

[0019] Further, in S1, the dynamic mold temperature high-temperature section and low-temperature section temperature match the temperature control capability of the dynamic mold temperature machine.

[0020] Further, in S1, the injection molding cycle matches the cooling efficiency of the dynamic mold temperature machine.

[0021] Further, in S1, the dynamic mold temperature machine pre-circulates to dynamically change the temperature of the mold, and determines the highest temperature, the lowest temperature, and the temperature change efficiency of different molds. The higher the highest temperature, the better the flatness and surface quality of the product. The lowest temperature affects the shrinkage of the product, and the temperature change efficiency affects the molding efficiency of the product.

[0022] The molding start template value is obtained in the following way:

[0023] Based on the curves of melt density with respect to temperature and pressure (melt density with respect to temperature and pressure curves are obtained by professional equipment testing, and different resins have different curves, generally temperature curves under different pressures), the ratio of dynamic mold temperature high-temperature to low-temperature is calculated, and the injection molding start and clamping completion volume ratio (high-temperature melt density / low-temperature melt density) is calculated. The injection molding start template value is set to reserve space to gradually reduce the volume during the dynamic clamping process. This part is controlled by the clamping system of the injection molding machine, and finally the clamping is completed, and the product is cooled in place.

[0024] Further, in S2, the real-time pressure of the injection resin melt is obtained by averaging the sampling values of multiple pressure sensors arranged inside the mold.

[0025] The real-time temperature of the injection resin melt is obtained by averaging the sampling values of multiple temperature sensors arranged inside the mold.

[0026] Further, in S2, after the mold is opened, the injection molding machine working state signal is transmitted to the dynamic mold temperature machine in real time, and the dynamic mold temperature machine heats the injection mold according to the working state signal. After the mold is closed, the injection molding machine controls the dynamic mold temperature based on the melt pressure.

[0027] Further, in S2, during the dynamic mold temperature control process, the cooling process is controlled by the dynamic mold temperature machine switching low-temperature / high-temperature cooling water, and the cooling rate is obtained based on the cooling water heat exchange capacity and the online temperature of the mold.

[0028] Further, in S2, after the mold is closed to the preset value, the injection program is started, and the injection molding machine is corrected online based on the melt pressure and melt temperature.

[0029] The pressure is too high, the cooling speed is accelerated, the mold closing speed is reduced, the pressure value is reduced when the cooling speed is accelerated, and the mold plate load is reduced; if the pressure is too low, the mold closing speed is accelerated, the cooling speed is reduced, and if the mold plate is too high during the mold closing process, the mold plate load priority is higher, the mold closing speed is corrected to reduce, and the cooling speed is adjusted to increase, so as to prevent instantaneous overload, and the motor load and energy consumption are optimized, so that the motor load is within a certain load limit.

[0030] Further, in S2, the mold closing rate of the mold during the injection molding process is matched and corrected by the variable mold temperature controller according to the melt pressure curve, so as to ensure a stable pressure curve.

[0031] Compared with the prior art, the present application has the following technical advantages:

[0032] 1) The present technical solution develops a dynamic mold locking and dynamic mold temperature collaborative technology based on intelligent control, introduces melt pressure, and realizes the improvement of resin crystallization performance through dynamic mold temperature and dynamic mold locking collaboration, so as to control the crystallinity and molecular chain distribution of the resin at constant pressure and variable temperature.

[0033] 2) The whole process is dynamically corrected in real time, and the mold motor load of the injection molding machine is also considered, which meets the development direction of green, environmental protection and intelligent manufacturing, and lays a good foundation for high melt viscosity injection molding. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 It is a schematic diagram of the principle of the dynamic mold locking and dynamic mold temperature collaborative injection molding process in the present technical solution. DETAILED DESCRIPTION

[0035] Referring to Figure 1 The dynamic mold locking and dynamic mold temperature collaborative injection molding process in the present application includes the following steps:

[0036] (1) First, set the target holding pressure of the injection molding, the dynamic mold temperature high temperature section / low temperature section temperature, the injection molding cycle, and the molding start mold plate value;

[0037] (2) Secondly, use the mold temperature and pressure sensor to realize online collection of the data of the injection grade resin, and the injection molding intelligent control process is corrected online according to the pressure and temperature of the injection resin melt, so as to ensure the consistency of the melt pressure, and the basic principle is that the pressure is too high, the cooling speed is accelerated, the pressure is too low, and the mold closing speed is accelerated, and the motor load and energy consumption are optimized, and the motor load is within a certain load limit;

[0038] (3) Finally, the injection molding mold plate is closed in place, the temperature is cooled to room temperature, and the mold is opened to take out the product.

[0039] Step (1) The target packing pressure of injection molding is automatically calculated to the maximum limit according to the input product area and the maximum clamping force of the injection molding machine, and the target packing pressure is only lower than the maximum limit; the high temperature / low temperature of the dynamic mold temperature is limited by the temperature control ability of the dynamic mold temperature machine, and the cooling efficiency of the dynamic mold temperature machine also determines the injection molding cycle. The dynamic mold temperature machine can pre-cycle to dynamically change the temperature of the mold to determine the highest temperature, the lowest temperature and the temperature changing efficiency of different molds. In addition, the starting template value is calculated by the ratio of the dynamic mold temperature high temperature and low temperature, and the volume ratio of the injection starting and clamping completion is calculated, so as to set the template starting value, and the clamping rate of the template in the molding process is automatically matched and corrected by the controller according to the melt pressure curve, so as to ensure the stable pressure curve. The high temperature / low temperature of the dynamic mold temperature is realized by the dynamic mold temperature machine, and the dynamic mold temperature machine is heated after the mold is opened. The injection molding machine controls the subsequent dynamic mold temperature according to the melt pressure, and the cooling program is switched to the low temperature cooling water control by the dynamic mold temperature machine, and the cooling rate is calculated based on the cooling water heat exchange amount and the online temperature of the mold.

[0040] Step (2) The injection program is started after the mold is clamped to a specific value, and the injection molding machine is corrected online according to the melt pressure and melt temperature. If the pressure is too high, the cooling speed will be accelerated, and if the pressure is too low, the clamping speed will be accelerated. In addition, the motor load and energy consumption are optimized, and the motor load is within a certain load limit.

[0041] Step (3) After the injection molding is completed, the cooling temperature needs to reach the set value at the same time, and the basic control principle is calculated by matching and coordinating the clamping speed and the cooling speed, and then the mold is opened and the product is taken out.

[0042] The present application will be described in detail below in combination with the drawings and specific examples. In this technical solution, if the structure / module name, control mode, algorithm, process or component ratio and other features are not explicitly stated, they are considered as common technical features disclosed in the prior art.

[0043] Example 1

[0044] The injection resin of this example is polyethylene, and the viscosity average molecular weight is 29×10 4g / mol, (1) the dynamic mold temperature machine was started in the preparation stage of the beginning of injection molding, and after cycle testing, the highest temperature of the dynamic mold temperature was 159°C, the lowest temperature was 20°C, the highest heating rate was 6°C / s, the cooling rate was 8°C / s, and the highest holding pressure of the injection molding machine was 60 MPa; (2) the target holding pressure was set to 40 MPa, the molding cycle was 90 s, and the high and low temperatures of the dynamic mold temperature were 100°C / 20°C (the shortest cycle was 24 s); (3) the melt glue amount and other injection molding parameters were the same as those in the conventional injection molding setting mode, after starting the injection molding, the mold was closed to the starting position, the mold temperature was raised to 100°C / s to start injection molding, the melt pressure reached 40 MPa after the start of injection molding, the injection was completed, the dynamic mold temperature machine was started to cool, the mold was slowly advanced, the holding pressure curve was maintained at 40 MPa and kept stable in real time, the mold plate motor load was monitored at the same time (60-80%), the mold was closed to the position after 68 s, the temperature reached 23°C, the cooling was continued for 6 s, the mold plate was opened to take out the product, and the product taking-out time was 2 s.

[0045] The mechanical properties of the prepared product are shown in Table 1.

[0046] Example 2

[0047] The injection molding resin in this example is polyethylene, and the viscosity average molecular weight is 630 x 10 4 g / mol, (1) the dynamic mold temperature machine was started in the preparation stage of the beginning of injection molding, and after cycle testing, the highest temperature of the dynamic mold temperature was 159°C, the lowest temperature was 20°C, the highest heating rate was 6°C / s, the cooling rate was 8°C / s, and the highest holding pressure of the injection molding machine was 60 MPa; (2) the target holding pressure was set to 40 MPa, the molding cycle was 90 s, and the high and low temperatures of the dynamic mold temperature were 100°C / 20°C (the shortest cycle was 24 s); (3) the melt glue amount and other injection molding parameters were the same as those in the conventional injection molding setting mode, after starting the injection molding, the mold was closed to the starting position, the mold temperature was raised to 100°C / s to start injection molding, the melt pressure reached 40 MPa after the start of injection molding, the injection was completed, the dynamic mold temperature machine was started to cool, the mold was slowly advanced, the holding pressure curve was maintained at 40 MPa and kept stable in real time, the mold plate motor load was monitored at the same time (60-80%), the mold was closed to the position after 68 s, the temperature reached 23°C, the cooling was continued for 6 s, the mold plate was opened to take out the product, and the product taking-out time was 2 s.

[0048] The mechanical properties of the prepared product are shown in Table 1.

[0049] Example 3

[0050] The injection molding resin in this example is polyethylene, and the viscosity average molecular weight is 630 x 10 4g / mol, (1) The dynamic mold temperature controller is started during the injection molding preparation stage. After cyclic testing, the highest temperature of the dynamic mold temperature is 159℃, the lowest temperature is 20℃, the highest heating rate is 6℃ / s, the cooling rate is 8℃ / s, and the highest holding pressure of the injection molding machine is 80MPa; (2) The target holding pressure is set to 60MPa, the molding cycle is 109s, and the dynamic mold temperature is 140℃ / 20℃ (shortest cycle is 38s); (3) The injection parameters such as melt volume are the same as those of traditional injection molding. After starting injection molding, the mold is closed to the starting position, the mold temperature is raised to 140℃ / s, and the injection begins. After the injection begins, the melt pressure reaches 60MPa and the injection ends. The dynamic mold temperature controller is cooled and started, the mold moves forward slowly, and the holding pressure curve is maintained at 60MPa in real time. At the same time, the template motor load (80%~96%) is monitored. After 82s, the mold is closed and the temperature reaches 26℃. After cooling for another 6s, the template is opened and the product is taken out. The product is taken out in 2s.

[0051] The mechanical properties of the prepared products are shown in Appendix Table 1.

[0052] Example 4

[0053] In this embodiment, the injection molding resin is polyethylene with a viscosity-average molecular weight of 29 × 10⁻⁶. 4 g / mol, (1) The dynamic mold temperature controller is started during the injection molding preparation stage. After cyclic testing, the highest temperature of the dynamic mold temperature is 159℃, the lowest temperature is 20℃, the highest heating rate is 6℃ / s, the cooling rate is 8℃ / s, and the highest holding pressure of the injection molding machine is 60MPa; (2) The target holding pressure is set to 60MPa, the molding cycle is 109s, and the dynamic mold temperature is 140℃ / 20℃ (shortest cycle is 38s); (3) The injection parameters such as melt volume are the same as those of traditional injection molding. After starting injection molding, the mold is closed to the starting position, the mold temperature is raised to 140℃ / s, and the injection begins. After the injection begins, the melt pressure reaches 60MPa and the injection ends. The dynamic mold temperature controller is started to cool down and the mold moves forward slowly. The holding pressure curve is maintained at 60MPa and kept stable in real time. At the same time, the template motor load (80-91%) is monitored. After 80s, the mold is closed and the temperature reaches 26℃. After cooling for another 8s, the template is opened and the product is taken out. The product is taken out in 2s.

[0054] The mechanical properties of the prepared products are shown in Appendix Table 1.

[0055] Example 5

[0056] In this embodiment, the injection molding resin is polyethylene with a viscosity-average molecular weight of 68 × 10⁻⁶. 4g / mol, (1) the dynamic mold temperature machine was started in the preparation stage of injection molding, and after cycle test, the highest temperature of the dynamic mold temperature was 159°C, the lowest temperature was 20°C, the highest heating rate was 6°C / s, the cooling rate was 8°C / s, and the highest holding pressure of the injection molding machine was 60 MPa; (2) the target holding pressure was set to 40 MPa, the molding cycle was 90 s, and the high and low temperatures of the dynamic mold temperature were 100°C / 40°C (the shortest cycle was 24 s); (3) the melt glue amount and other injection molding parameters were the same as those set in the traditional injection molding, after starting the injection molding, the mold was closed to the starting position, the mold was heated to 100°C / s to start injection molding, the melt pressure reached 40 MPa to end the glue injection after the injection molding started, the dynamic mold temperature machine was started to cool, the mold was slowly advanced, the holding pressure curve was maintained at 40 MPa to keep stable in real time, the mold plate motor load was monitored at the same time (60% to 80%), the mold was closed to the position after 68 s, the temperature reached 40°C, the mold was opened to take out the product after 9 s of continuous cooling, and the product taking-out time was 3 s.

[0057] The mechanical properties of the prepared product are shown in Table 1.

[0058] Example 6

[0059] The injection molding resin in this example was polyethylene, and the viscosity average molecular weight was 630×10 4 g / mol, (1) the dynamic mold temperature machine was started in the preparation stage of injection molding, and after cycle test, the highest temperature of the dynamic mold temperature was 159°C, the lowest temperature was 20°C, the highest heating rate was 6°C / s, the cooling rate was 8°C / s, and the highest holding pressure of the injection molding machine was 60 MPa; (2) the target holding pressure was set to 40 MPa, the molding cycle was 90 s, and the high and low temperatures of the dynamic mold temperature were 100°C / 40°C (the shortest cycle was 24 s); (3) the melt glue amount and other injection molding parameters were the same as those set in the traditional injection molding, after starting the injection molding, the mold was closed to the starting position, the mold was heated to 100°C / s to start injection molding, the melt pressure reached 40 MPa to end the glue injection after the injection molding started, the dynamic mold temperature machine was started to cool, the mold was slowly advanced, the holding pressure curve was maintained at 40 MPa to keep stable in real time, the mold plate motor load was monitored at the same time (60% to 80%), the mold was closed to the position after 68 s, the temperature reached 40°C, the mold was opened to take out the product after 9 s of continuous cooling, and the product taking-out time was 3 s.

[0060] The mechanical properties of the prepared product are shown in Table 1.

[0061] Comparative Example 1

[0062] Blank comparison

[0063] The injection molding resin in this example was polyethylene, and the viscosity average molecular weight was 29×10 4The injection molding parameters such as the amount of melt were the same as in Example 1. After starting the injection molding, the mold was closed to position, and the injection molding was completed by injection, pressure holding, and cooling. The product was removed after the injection molding was completed.

[0064] The mechanical properties of the prepared product are shown in Table 1.

[0065] Comparative Example 2

[0066] Blank comparison

[0067] The injection resin in this example was polyethylene with a viscosity average molecular weight of 68 x 10 4 The injection molding parameters such as the amount of melt were the same as in Example 2. After starting the injection molding, the mold was closed to position, and the injection molding was completed by injection, pressure holding, and cooling. The product was removed after the injection molding was completed.

[0068] The mechanical properties of the prepared product are shown in Table 1.

[0069] Comparative Example 3

[0070] Blank comparison

[0071] The injection resin in this example was polyethylene with a viscosity average molecular weight of 29 x 10 4 The injection molding parameters such as the amount of melt were the same as in Example 6. After starting the injection molding, the mold was closed to position, and the injection molding was completed by injection, pressure holding, and cooling. The product was removed after the injection molding was completed.

[0072] The mechanical properties of the prepared product are shown in Table 1.

[0073] Table 1 Mechanical properties of injection molded products of examples

[0074] Examples Tensile strength / Mpa Elongation at break / % Crystallinity / % 1 27.9 630 62 2 31.8 368 60 3 35.9 296 55 4 28.3 626 62 5 31.9 359 60 6 36.3 282 58 Blank (2.9 million) 23.8 680 58 Blank (6.8 million) 29.6 390 55 Blank (63 million) 33.8 298 53

[0075] The above description of the examples is for the purpose of enabling one of ordinary skill in the art to understand and use the invention. Various modifications to these examples can be made by those skilled in the art without departing from the spirit and scope of the invention, and the general principles described herein can be applied to other examples without the use of inventive faculty. Therefore, the present invention is not limited to the above examples, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of the present invention.

Claims

1. A dynamic mode locking and dynamic mold temperature collaborative injection molding process, characterized in that, The method comprises the following steps: S1: setting a target packing pressure of injection molding, a high-temperature section and a low-temperature section temperature of a dynamic mold temperature, a molding start template value, and an injection molding cycle; S2: performing online correction according to real-time pressure and temperature of the injection resin melt, so as to ensure constant melt pressure; S3: closing the injection molding mold to position, waiting for the temperature to cool to room temperature, and opening the mold to take out the product; In S1, the target packing pressure of injection molding is obtained in the following manner: calculating a maximum pressure limit according to the input product area and the maximum clamping force of the injection molding machine, and selecting a pressure value smaller than the maximum pressure limit as the target packing pressure; In S1, the dynamic mold temperature machine pre-circulates to dynamically change the temperature of the mold, and determines the highest temperature, the lowest temperature, and the temperature change efficiency of different molds; The molding start template value is obtained in the following manner: calculating the ratio of the dynamic mold temperature high-temperature section to the low-temperature section based on the curves of the melt density and the temperature and the pressure, so as to calculate the injection molding start and mold closing completion volume ratio, and set the injection molding start template value; In S2, the real-time pressure of the injection resin melt is obtained by averaging the sampling values of a plurality of pressure sensors arranged in the mold; The real-time temperature of the injection resin melt is obtained by averaging the sampling values of a plurality of temperature sensors arranged in the mold.

2. A dynamic mode locking and dynamic mold temperature coordinated injection molding process according to claim 1, wherein, In S1, the dynamic mold temperature high-temperature section and the low-temperature section temperature are matched with the temperature control capability of the dynamic mold temperature machine.

3. A dynamic mode locking and dynamic mold temperature collaborative injection molding process according to claim 1, wherein, In S1, the injection molding cycle is matched with the cooling efficiency of the dynamic mold temperature machine.

4. A dynamic mode locking and dynamic mold temperature collaborative injection molding process according to claim 1, wherein, In S2, the mold opening state signal of the injection molding machine is transmitted to the dynamic mold temperature machine in real time, and the dynamic mold temperature machine heats the injection mold according to the working state signal; after the mold closing starts, the injection molding machine performs dynamic mold temperature control according to the melt pressure.

5. A dynamic mode locking and dynamic mold temperature collaborative injection molding process according to claim 4, wherein, In S2, during the dynamic mold temperature control process, the cooling process is switched by the dynamic mold temperature machine to control the low-temperature / high-temperature cooling water, and the cooling rate is obtained based on the cooling water heat exchange amount and the online temperature of the mold.

6. A dynamic mode locking and dynamic mold temperature collaborative injection molding process as claimed in claim 1 wherein, In S2, after the mold closing reaches the preset value, the injection program is started, and the injection molding machine performs online correction according to the melt pressure and the melt temperature.

7. A dynamic mode locking and dynamic mold temperature collaborative injection molding process according to claim 6, wherein, In S2, the mold closing rate of the mold during the injection molding process is matched and corrected by the variable mold temperature controller according to the melt pressure curve, so as to ensure a stable pressure curve.

Images