Fixed dummy block for extrusion press equipment and method for determining deterioration of container liners

Abstract

To provide a deterioration determination method of a fixed dummy block and a container liner of an extruding press device.SOLUTION: A deterioration determination method of a fixed dummy block of an extruding press device and a container liner includes a fixed dummy block sliding waveform measuring process of measuring at least one of a waveform of an actual pressure generated on a hydraulic actuator and a waveform of an actual sliding speed of the hydraulic actuator upon the sliding of a fixed dummy block and a deterioration determination process of comparing the measured wave form with a preset corresponding standard waveform. In the deterioration determination process, when the waveform measured by the fixed dummy block sliding waveform measuring process exceeds allowance preset from the corresponding standard waveform, it is determined that at least one side of the fixed dummy block and the container liner is deteriorated.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a fixed dummy block for an extrusion press and a method for determining deterioration of a container liner. [Background technology]

[0002] An extrusion press is a device that manufactures aluminum products by pressing an easily processable metal material, such as aluminum or its alloy (hereinafter referred to as aluminum material), against a die and continuously extruding (extrusion molding) aluminum products of a predetermined cross-sectional shape from the die. The die has an opening that mimics the cross-sectional shape of the aluminum product, and the extruded long aluminum product is cut to the specified length to become individual aluminum products.

[0003] A conventional extrusion press and its extrusion process will be described with reference to Figure 1. Figure 1 is a schematic cross-sectional side view showing an outline of the configuration of an extrusion press, with detailed configuration illustrations omitted. The aluminum material to be extruded is formed into a cylindrical billet B with a predetermined diameter corresponding to the aluminum product W to be manufactured, and is inserted into a billet storage section in a container 1. This billet storage section is made up of a container liner (not shown) inserted into the container 1 body and separate from the container 1 body.

[0004] The main cylinder 4, which generates extrusion pressure, is a hydraulic cylinder with only an oil chamber for advancing the cylinder rod, and the main ram 4a corresponds to the cylinder rod. The extrusion stem 3 is attached to the main ram 4a. A fixed dummy block (not shown) is attached to the tip of the extrusion stem 3. When the main ram 4a (ram position) moves toward the die 2 (forward / right side in Figure 1) due to hydraulic oil supplied to the oil chamber of the main cylinder 4 from the main pump unit 5 via a hydraulic circuit, the extrusion stem 3 also moves (forward), pressing the billet B against the die 2. This pressure pressurizes the billet B within the container 1 and continuously extrudes it through the opening of the die 2, which resembles the cross-sectional shape of the aluminum product W. Reference numeral 10 denotes an end platen, and 10a denotes a pressure ring embedded in the end platen 10 that receives the pressing force acting on the die 2. For simplicity's sake, the main pump unit 5 is illustrated as a hydraulic pump in Figure 1.

[0005] Repeated extrusion processes can cause scratches on the inner circumferential surface of the container liner and adhesion of the aluminum material of billet B. Similarly, the fixed dummy block expands under extrusion pressure and remains expanded, resulting in scratches on its outer circumferential surface and adhesion of the aluminum material of billet B. Such deterioration of the container liner and the fixed dummy block can cause fluctuations in the sliding resistance of the fixed dummy block, affecting the extrusion speed and extrusion pressure, and can also cause the adhered aluminum material to be mixed into the extruded product, thereby affecting the quality of the extruded product. For this reason, manufacturers of extruded products replace the container liner and the fixed dummy block based on their experience of visually checking the adhesion of aluminum material to these components, or periodically replace the container liner and the fixed dummy block. Patent Document 1 also discloses a tubular body inspection device used to inspect the inner surface of a container liner. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-169570 Summary of the Invention [Problem to be solved by the invention]

[0007] In the periodic or experience-based replacement of container liners and fixed dummy blocks as described above, problems arise such as replacing items that are still usable or delaying the replacement, causing problems in the operation of the extrusion press device.

[0008] The present invention has been made in consideration of the above-mentioned problems, and has an object to provide a method for determining deterioration of a fixed dummy block and a container liner of an extrusion press apparatus, which determines that at least one of the fixed dummy block and the container liner has deteriorated by measuring at least one of the waveform of the actual pressure generated in a hydraulic actuator and the waveform of the actual sliding speed of the hydraulic actuator when the fixed dummy block slides and comparing the waveform with a reference waveform. [Means for solving the problem]

[0009] The object of the present invention is to provide a hydraulic actuator having a fixed dummy block sliding waveform measuring step for measuring at least one of the waveform of the actual pressure generated in the hydraulic actuator and the waveform of the actual sliding speed of the hydraulic actuator when the fixed dummy block slides; a deterioration determination step of comparing at least one of the waveform of the actual pressure generated in the hydraulic actuator and the waveform of the actual sliding speed of the hydraulic actuator, which are measured in the fixed dummy block sliding waveform measurement step, with a corresponding preset reference waveform, This is achieved by a method for determining deterioration of a fixed dummy block and a container liner of an extrusion press apparatus, characterized in that in the deterioration determination process, if at least one of the waveform of the actual pressure generated in the hydraulic actuator and the waveform of the actual sliding speed of the hydraulic actuator measured in the fixed dummy block sliding waveform measurement process exceeds a preset allowable value from the corresponding reference waveform, it is determined that at least one of the fixed dummy block and the container liner is deteriorated.

[0010] Furthermore, in the method of determining deterioration of the fixed dummy block and container liner of an extrusion press apparatus according to the present invention, it is preferable that the reference waveform is at least one of the waveform of the actual pressure generated in the hydraulic actuator and the waveform of the actual sliding speed of the hydraulic actuator when the fixed dummy block slides after the fixed dummy block and the container liner are replaced or after cleanout of the container is performed.

[0011] Furthermore, in the method of determining deterioration of a fixed dummy block and a container liner of an extrusion press device according to the present invention, it is preferable that the sliding of the fixed dummy block occurs when the fixed dummy block inserts a billet into the container using an extrusion stem equipped at the front end thereof, and that the hydraulic actuator is a side cylinder.

[0012] In this case, it may be determined that the fixed dummy block has deteriorated if the waveform of the actual pressure generated in the side cylinder exceeds the preset allowable value from the initial stage when the fixed dummy block is inserted into the container liner when the billet is inserted into the container, based on the corresponding reference waveform.

[0013] On the other hand, in the method for determining deterioration of a fixed dummy block and a container liner of an extrusion press device according to the present invention, the sliding of the fixed dummy block may be when the main ram retreats alone after the extrusion process, after the container strip operation, and after the container and main ram have retreated simultaneously, and the hydraulic actuator may be a side cylinder that retreats the main ram.

[0014] In the method of determining deterioration of a fixed dummy block and a container liner of an extrusion press device according to the present invention, the sliding of the fixed dummy block may be performed after the extrusion process, after the container strip operation, and after the simultaneous retraction of the container and main ram, when the main ram retracts alone, and the hydraulic actuator may be a container cylinder in which the supply and discharge of hydraulic oil has been stopped.

[0015] Furthermore, in the method for determining deterioration of the fixed dummy block and container liner of an extrusion press apparatus according to the present invention, the number of operations since the replacement of the fixed dummy block and the container liner or the execution of a cleanout of the container, when a determination of deterioration of the fixed dummy block and the container liner has been made in the deterioration determination step, may be stored as a deterioration determination operation count, and a deterioration alarm may be issued according to the stage from a predetermined number of times before the number of operations since the next replacement of the fixed dummy block and the container liner or the next execution of a cleanout of the container reaches the deterioration determination operation count until the number of operations reaches the deterioration determination operation count. [Effects of the Invention]

[0016] The method for determining deterioration of a fixed dummy block and a container liner of an extrusion press according to the present invention includes a fixed dummy block sliding waveform measurement step of measuring at least one of the waveform of the actual pressure generated in the hydraulic actuator and the waveform of the actual sliding speed of the hydraulic actuator when the fixed dummy block slides; a deterioration determination step of comparing at least one of the waveform of the actual pressure generated in the hydraulic actuator and the waveform of the actual sliding speed of the hydraulic actuator, which are measured in the fixed dummy block sliding waveform measurement step, with a corresponding preset reference waveform, In the deterioration determination step, if at least one of the waveform of the actual pressure generated in the hydraulic actuator and the waveform of the actual sliding speed of the hydraulic actuator measured in the fixed dummy block sliding waveform measurement step exceeds a preset allowable value from the corresponding reference waveform, it is determined that at least one of the fixed dummy block and the container liner has deteriorated, so a method for determining that at least one of the fixed dummy block and the container liner has deteriorated can be provided. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a schematic cross-sectional side view showing an outline of the configuration of an extrusion press device. [Figure 2] FIG. 2 is a schematic plan view (partially in cross section) illustrating insertion of a billet into a container. [Figure 3] 4 is a graph illustrating a fixed dummy block sliding waveform measuring step and a deterioration determining step in the first embodiment. [Figure 4] This is a schematic plan view (partially in cross section) illustrating the time when the main ram independently retreats after the extrusion process, the container strip operation, and the simultaneous retreat of the container and main ram. [Figure 5] 10 is a graph illustrating a fixed dummy block sliding waveform measuring step and a deterioration determining step in the second embodiment. [Figure 6] 10 is a graph illustrating a fixed dummy block sliding waveform measuring step and a deterioration determining step in the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the inventions according to the claims, and not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0019] [First embodiment] A method for determining deterioration of a fixed dummy block and a container liner of an extrusion press apparatus according to a first embodiment will be described with reference to Figures 2 and 3. In the first embodiment, the fixed dummy block slides when inserting a billet into a container using an extrusion stem attached to the front end of the fixed dummy block, and the hydraulic actuator is a side cylinder. First, the insertion of a billet into a container will be described with reference to Figure 2.

[0020] As shown in FIG. 2(a), a container cylinder 21 presses a container 1 against a die 2, and a billet loader 22 carrying a billet B is moved to the extrusion center between the container 1 and the retracted extrusion stem 3. Thereafter, as shown in FIG. 2(b), a side cylinder (only a cylinder rod 23 is shown) advances the main ram 4a and extrusion stem 3, and the extrusion stem 3, which has a fixed dummy block 3a attached to its front end, inserts the billet B into a billet insertion section (container liner 24) in the container 1. Note that in FIG. 2, the end platen 10 side of the extrusion press device (left side in FIG. 2) is referred to as the front, and movement of the components toward the end platen 10 side is referred to as the forward movement, the main ram 4a side (right side in FIG. 2) is referred to as the rear, and movement of the components toward the main ram 4a side is referred to as the retraction.

[0021] In the first embodiment, as described above, when a billet is inserted into a container by an extrusion stem equipped at the front end of a fixed dummy block, a fixed dummy block sliding waveform measuring process is performed to measure at least one of the waveform of the actual pressure generated in the side cylinder, which is a hydraulic actuator, and the waveform of the actual sliding speed of the side cylinder (cylinder rod). Then, a deterioration determination process is performed to compare at least one of the waveform of the actual pressure generated in the side cylinder and the waveform of the actual sliding speed of the cylinder rod of the side cylinder, measured in the fixed dummy block sliding waveform measuring process, with a corresponding preset reference waveform.

[0022] The fixed dummy block sliding waveform measurement process and deterioration determination process in the first embodiment will be described with reference to Figure 3. Figure 3(a) is a reference waveform described later, Figure 3(b) shows the increase in actual pressure of the side cylinder and the decrease in actual sliding speed due to deterioration of the fixed dummy block and container liner, and Figure 3(c) shows the fluctuations in actual pressure and actual sliding speed of the side cylinder due to deterioration of the fixed dummy block and container liner.

[0023] First, the reference waveform shown in Figure 3(a) will be described. The reference waveform shown in Figure 3(a) was measured when a billet was inserted into a container using an extrusion stem attached to the front end of the fixed dummy block after replacing the fixed dummy block and the container liner, or after cleaning out the container. The reference waveform is used as a basis for determining deterioration of the fixed dummy block 3a and the container liner 24. Therefore, it is preferable that the reference waveform be the waveform of the actual pressure generated in the hydraulic actuator and the waveform of the actual sliding speed of the cylinder rod of the hydraulic actuator in an initial state in which the fixed dummy block 3a is not expanded and has no scratches or aluminum material attached to its outer circumferential surface, and the container liner 24 has no scratches or aluminum material attached to its inner circumferential surface, i.e., after replacing the fixed dummy block and the container liner. However, it may also be the waveform of the actual pressure generated in the hydraulic actuator and the waveform of the actual sliding speed of the cylinder rod of the hydraulic actuator after cleanout of the container has been performed, in which the aluminum material adhering to the inner surface of the container liner has been removed. The horizontal axis of Figure 3(a) represents the forward movement of the push-out stem 3 from the right side to the left side in Figure 3 at position L of the push-out stem 3, the left vertical axis represents the actual pressure P1 generated in the side cylinder, and the right vertical axis represents the actual sliding speed V1 of the side cylinder.

[0024] In the reference waveform, the fixed dummy block 3a and the container liner 24 are in the initial state described above, so when the billet B is inserted into the container 1 (container liner 24) by the extrusion stem 3, no unnecessary insertion resistance is generated in the billet B. Therefore, as shown in Figure 3(a), there is no increase, decrease, or fluctuation in the actual pressure P1 and actual sliding speed V1 generated in the side cylinder.

[0025] In Figure 3(a), the peak of the actual pressure P1 during billet insertion and upsetting occurs when one end of the billet B pressed against the extrusion stem 3 comes into contact with the die 2. The extrusion stem 3 advances by opening the prefill valve (a valve that connects or disconnects the piping between the oil chamber of the main ram 4a and the hydraulic oil tank) of the main ram 4a and advancing the side cylinder. As the side cylinder advances, hydraulic oil is drawn into the oil chamber (not shown) of the main ram 4a from the hydraulic oil tank (not shown) via the open prefill valve (not shown). Then, during the subsequent upsetting, the oil chamber (not shown) that advances the side cylinder and the prefill valve are closed, allowing hydraulic oil to be supplied to the oil chamber of the main ram 4a as well. Upsetting is a process in which the billet B is pressed with a pressing force that does not cause the billet B to be extruded from the die 2, causing plastic deformation so that the billet B expands in the radial direction, thereby bringing the outer peripheral surface of the billet B into close contact with the inner peripheral surface of the container 1 (container liner 24). The actual pressure P1, which had dropped once due to the opening and closing of the prefill valve, rises again when upsetting begins, and in contrast, the actual sliding speed V1, which had been constant when the billet was inserted, decreases.

[0026] Meanwhile, as described above, repeated extrusion processes cause the fixed dummy block 3a to expand, scratching its outer circumferential surface and causing the aluminum material of the billet B to adhere thereto. Furthermore, the inner circumferential surface of the container liner 24 is also scratched and the aluminum material of the billet B adheres thereto. Therefore, the fixed dummy block 3a causes fluctuations in the insertion resistance when the billet B is inserted into the container 1 (container liner 24). Due to this fluctuation in insertion resistance, the actual pressure P1 of the side cylinder during billet insertion increases by dp1 (fluctuation value) compared to the reference waveform, and the actual sliding velocity decreases by dv1 (fluctuation value) compared to the reference waveform. Figure 3(b) shows a waveform measured in this state. The dashed line indicates the reference waveform. In the first embodiment, such a waveform is measured in the fixed dummy block sliding waveform measurement process when the billet B is inserted into the container liner 24.

[0027] Then, a deterioration determination process is performed in which the waveform as shown in Fig. 3(b) measured in the fixed dummy block sliding waveform measurement process is compared with the reference waveform shown in Fig. 3(a). In the deterioration determination process, the fluctuation values ​​for the reference waveform calculated from the measured actual waveform are compared with preset allowable values ​​for the actual pressure and actual sliding speed, which are allowable deviations from the reference waveform. For example, if at least one of the fluctuation values ​​dp1 and dv1 in Fig. 3(b) exceeds the corresponding allowable value, it is determined that at least one of the fixed dummy block 3a and the container liner 24 has deteriorated.

[0028] Furthermore, when the billet B is inserted into the container 1 (container liner 24) by the fixed dummy block 3a, fluctuations in insertion resistance due to unevenness of the attached aluminum material may be measured as waveform variations as shown in FIG. 3(c). In FIG. 3(c), assuming that the maximum variation in the actual pressure P1 is kp1 and the maximum variation in the actual sliding speed is kv1, the maximum variation calculated from the measured actual waveforms is compared with preset allowable values ​​for the variation in the actual pressure and the actual sliding speed. For example, if at least one of the maximum variation ranges kp1 and kv1 in FIG. 3(c) exceeds the corresponding allowable value, it is determined that at least one of the fixed dummy block 3a and the container liner 24 has deteriorated. In addition to or instead of the variation ranges, the peak values ​​of the measured actual pressure P1 and the actual sliding speed V1 as shown in FIG. 3(c) may be compared with the corresponding allowable peak values.

[0029] 3(b), that is, when the actual pressure P1 exceeds a preset allowable value from the initial stage when the fixed dummy block 3a is inserted into the container liner 24 during insertion of the billet B into the container 1. This is because the length of the container liner 24 of the container 1 is longer than the overall length of the inserted billet B, and there is an area on the extrusion stem 3 side of the container liner 24 that does not come into contact with the billet B when the billet B expands radially in the upsetting process described above. In this area, deterioration due to scratches on the inner circumferential surface of the container liner 24 or adhesion of aluminum material can be ignored, and therefore, fluctuations in the actual pressure P1 caused by increased insertion resistance when the fixed dummy block 3a slides in this area can be determined to be due to deterioration of the outer circumferential surface of the fixed dummy block 3a.

[0030] In this way, the method for determining deterioration of a fixed dummy block and a container liner of an extrusion press apparatus includes a fixed dummy block sliding waveform measurement step of measuring the waveform of the actual pressure generated in the side cylinder, which is a hydraulic actuator, and the waveform of the actual sliding speed of the side cylinder (cylinder rod) when the fixed dummy block inserts a billet into a container using the extrusion stem equipped at its front end, and a deterioration determination step of comparing the measured waveforms with reference waveforms. This method can determine the deterioration of the fixed dummy block and the container liner of the extrusion press apparatus based on certain criteria. Furthermore, by notifying the operator of this deterioration determination via a display device or a voice generating device of the extrusion press apparatus, the fixed dummy block and the container liner can be replaced at an appropriate time regardless of experience, thereby avoiding the need to replace something that is still usable or the problem of delayed replacement causing disruption to the operation of the extrusion press apparatus.

[0031] [Second embodiment] A method for determining deterioration of a fixed dummy block and a container liner of an extrusion press apparatus according to a second embodiment will be described with reference to Figures 4 and 5. In the second embodiment, the fixed dummy block slides after the extrusion process, after the container strip operation, and when the main ram independently retracts after the container and main ram have simultaneously retracted, and the hydraulic actuator is a side cylinder that retracts the main ram. First, with reference to Figure 4, the independent retraction of the main ram after the container and main ram have simultaneously retracted will be described.

[0032] FIG. 4(a) shows the state after the container strip operation, in which the container 1 is retracted by the container cylinder 21 after the extrusion process is completed, exposing the discard 25 (remaining extrusion of billet B) in the container 1 (container liner 24) to the die 2 side so that the discard 25 (remaining extrusion of billet B) can be cut by the shear device. From the state shown in FIG. 4(a), the container 1 is retracted to the rearmost position by the container cylinder 21, and in conjunction with the retraction of the container 1, the main ram 4a and the extrusion stem 3 are retracted by the side cylinder (only the cylinder rod 23 is shown). That is, the container 1 and the extrusion stem 3 are retracted together from the state shown in FIG. 4(a) to the state shown in FIG. 4(b) where the container 1 is at the rearmost position. Note that when the container 1 is at the rearmost position shown in FIG. 4(b), the container cylinder 21 is not at the rearmost position, and the supply and discharge of hydraulic oil to and from the container cylinder 21 is stopped. In addition, in the state shown in FIG. 4(b), the discard 25 is cut by the shear device (not shown).

[0033] From the state shown in Figure 4(b), as shown in Figure 4(c), the side cylinder retracts the main ram 4a independently to the retract limit position. At this time, the fixed dummy block 3a slides inside the container liner 24 inside the container 1. In Figure 4, the end platen 10 side of the extrusion press device (left side in Figure 4) is the forward direction, and the movement of the components toward the end platen 10 side is the forward direction, while the main ram 4a side (right side in Figure 2) is the rearward direction, and the movement of the components toward the main ram 4a side is the retraction direction.

[0034] In the second embodiment, as described above, a fixed dummy block sliding waveform measuring process is performed to measure at least one of the waveform of the actual pressure generated in the side cylinder, which is a hydraulic actuator, and the waveform of the actual sliding speed of the side cylinder (cylinder rod), when the main ram retreats alone after the push-out process, after the container strip operation, and after the container and main ram retreat simultaneously. Then, a deterioration determination process is performed to compare at least one of the waveform of the actual pressure generated in the side cylinder and the waveform of the actual sliding speed of the cylinder rod of the side cylinder, measured in the fixed dummy block sliding waveform measuring process, with a corresponding preset reference waveform.

[0035] The fixed dummy block sliding waveform measurement process and deterioration determination process in the second embodiment will be described with reference to Figure 5. Figure 5(a) is a reference waveform described later, Figure 5(b) shows the increase in actual pressure of the side cylinder and the decrease in actual sliding speed due to deterioration of the fixed dummy block and container liner, and Figure 5(c) shows the fluctuations in actual pressure and actual sliding speed of the side cylinder due to deterioration of the fixed dummy block and container liner.

[0036] First, the reference waveform shown in Figure 5(a) will be described. The reference waveform shown in Figure 5(a) was measured when the main ram independently retreated after the fixed dummy block and container liner were replaced, or after the container was cleaned out, after the extrusion process, after the container strip operation, and after the container and main ram simultaneously retreated. Because the reference waveform serves as a basis for determining deterioration of the fixed dummy block 3a and the container liner 24, it is preferable that the reference waveform be the waveform of the actual pressure generated in the hydraulic actuator and the waveform of the actual sliding speed of the cylinder rod of the hydraulic actuator after the fixed dummy block 3a is not expanded and its outer circumferential surface is free of scratches or aluminum material attached, and the inner circumferential surface of the container liner 24 is free of scratches or aluminum material attached, i.e., after the fixed dummy block and container liner are replaced. However, it may also be the waveform of the actual pressure generated in the hydraulic actuator and the waveform of the actual sliding speed of the cylinder rod of the hydraulic actuator after cleanout of the container has been performed, in which the aluminum material adhering to the inner surface of the container liner has been removed. The horizontal axis of Figure 5(a) represents the retraction movement of the push-out stem 3 from left to right in Figure 5 at position L of the push-out stem 3, the left vertical axis represents the actual pressure P2 generated in the side cylinder, and the right vertical axis represents the actual sliding speed V2 of the side cylinder.

[0037] In the reference waveform, the fixed dummy block 3a and the container liner 24 are in the initial state described above, so when the main ram moves backward independently after the container and main ram move backward simultaneously, no unnecessary sliding resistance occurs between the outer peripheral surface of the fixed dummy block 3a and the inner peripheral surface of the container liner 24. Therefore, as shown in Figure 5(a), there is no increase / decrease or fluctuation in the actual pressure P2 and actual sliding speed V2 generated in the side cylinder.

[0038] On the other hand, as described above, repeated extrusion processes cause the fixed dummy block 3a to expand, scratching its outer circumferential surface and causing the aluminum material of the billet B to adhere thereto. Furthermore, the inner circumferential surface of the container liner 24 is also scratched and the aluminum material of the billet B adheres thereto. Therefore, after the container and main ram simultaneously retract, the sliding resistance of the fixed dummy block 3a in the container liner 24 fluctuates during the retraction of the main ram independently. Due to this sliding resistance fluctuation, the actual pressure P2 of the side cylinder during the retraction of the main ram 4a (extrusion stem 3) increases by dp2 (a fluctuation value) compared to the reference waveform, and the actual sliding velocity decreases by dv2 (a fluctuation value) compared to the reference waveform. The dashed line indicates the reference waveform. In the second embodiment, such a waveform is measured in the fixed dummy block sliding waveform measurement process during the retraction of the main ram independently after the container and main ram simultaneously retract.

[0039] Then, a deterioration determination process is performed in which the waveform as shown in Fig. 5(b) measured in the fixed dummy block sliding waveform measurement process is compared with the reference waveform shown in Fig. 5(a). In the deterioration determination process, the fluctuation values ​​for the reference waveform calculated from the measured actual waveform are compared with preset allowable values ​​for the actual pressure and actual sliding speed that are allowable deviations from the reference waveform, and if, for example, at least one of the fluctuation values ​​dp2 and dv2 in Fig. 5(b) exceeds the corresponding allowable value, it is determined that at least one of the fixed dummy block 3a and the container liner 24 has deteriorated.

[0040] Furthermore, fluctuations in sliding resistance during the retreating movement of the fixed dummy block 3a inside the container liner 24 may be measured as waveform variations as shown in FIG. 5(c) due to unevenness of the attached aluminum material, etc. In FIG. 5(c), if the maximum variation range of the actual pressure P2 is kp2 and the maximum variation range of the actual sliding velocity V2 is kv2, the maximum variation range calculated from the measured actual waveform is compared with a preset allowable variation range value for the actual pressure and actual sliding velocity. For example, if at least one of the maximum variation ranges kp2 and kv2 in FIG. 5(c) exceeds the corresponding allowable variation range value, it is determined that at least one of the fixed dummy block 3a and the container liner 24 has deteriorated. In addition to or instead of the variation range, the peak values ​​of the measured actual pressure P2 and actual sliding velocity V2 as shown in FIG. 5(c) may be compared with the allowable peak values.

[0041] In this way, the method for determining deterioration of the fixed dummy block and container liner of an extrusion press apparatus includes a fixed dummy block sliding waveform measurement step of measuring the waveform of the actual pressure generated in the side cylinder, which is a hydraulic actuator, and the waveform of the actual sliding speed of the side cylinder (cylinder rod), when the main ram independently retracts after the extrusion process, after the container strip operation, and after the container and main ram simultaneously retract, and a deterioration determination step of comparing the measured waveforms with reference waveforms. This deterioration determination can be determined based on certain criteria. Furthermore, by notifying the operator of this deterioration determination via a display device or a sound generating device of the extrusion press apparatus, the fixed dummy block and container liner can be replaced at an appropriate time regardless of experience, thereby avoiding problems such as replacing something that is still usable or delaying replacement and causing disruption to the operation of the extrusion press apparatus.

[0042] [Third embodiment] A method for determining deterioration of a fixed dummy block and a container liner of an extrusion press apparatus according to a third embodiment will be described with reference to Figures 4 and 6. In the third embodiment, the fixed dummy block slides after the extrusion process, after the container strip operation, and after the simultaneous retraction of the container and main ram, when the main ram retracts independently, and the hydraulic actuator is a container cylinder for which the supply and discharge of hydraulic oil has been stopped. Note that the independent retraction of the main ram after the simultaneous retraction of the container and main ram was explained in the second embodiment with reference to Figure 4, so a detailed explanation will be omitted.

[0043] In the third embodiment, as described above, a fixed dummy block sliding waveform measuring process is performed to measure the waveform of the actual pressure generated in the container cylinder, which is a hydraulic actuator, when the main ram independently retreats after the push-out process, the container strip operation, and the simultaneous retreat of the container and main ram. Then, a deterioration determination process is performed to compare the waveform of the actual pressure generated in the container cylinder measured in the fixed dummy block sliding waveform measuring process with a corresponding preset reference waveform.

[0044] The fixed dummy block sliding waveform measurement process and deterioration determination process in the third embodiment will be described with reference to Fig. 6. Fig. 6(a) shows a reference waveform, which will be described later, and Fig. 6(b) shows the increase in actual pressure in the container cylinder due to deterioration of the fixed dummy block and container liner.

[0045] First, the reference waveform shown in FIG. 6(a) will be described. The reference waveform shown in FIG. 6(a) is a waveform measured of the actual pressure generated in the container cylinder (hydraulic actuator) when the main ram independently retreats after the fixed dummy block and container liner are replaced, or after the container is cleaned out, the extrusion process, the container strip operation, and the simultaneous retreat of the container and main ram. Because the reference waveform is a waveform used as a reference for assessing the deterioration of the fixed dummy block 3a and the container liner 24, it is preferable that the reference waveform is the actual pressure waveform generated in the hydraulic actuator in an initial state in which the fixed dummy block 3a is not expanded and has no scratches or aluminum material attached to its outer circumferential surface, and the container liner 24 has no scratches or aluminum material attached to its inner circumferential surface, i.e., after the fixed dummy block and container liner are replaced. However, the reference waveform may also be the waveform of the actual pressure generated in the hydraulic actuator and the actual sliding speed of the cylinder rod of the hydraulic actuator after the container is cleaned out and aluminum material attached to the inner circumferential surface of the container liner is removed. The horizontal axis of FIG. 6(a) represents the retraction movement of the ejection stem 3 from the left side to the right side of FIG. 6 at the position L of the ejection stem 3, and the vertical axis represents the actual pressure P3 generated in the container cylinder.

[0046] As explained above, when the main ram independently retracts after the container and main ram simultaneously retract, the container cylinder 21 is not at its retract limit, and the supply and discharge of hydraulic oil to and from the container cylinder 21 is stopped. Therefore, if unnecessary sliding resistance occurs between the outer peripheral surface of the fixed dummy block 3a and the inner peripheral surface of the container liner 24 during independent retraction of the main ram, the cylinder rod of the container cylinder 21 is pulled backward, and the actual pressure P3 in the container cylinder increases. However, in the reference waveform, the fixed dummy block 3a and the container liner 24 are in the initial state described above, so unnecessary sliding resistance does not occur between the outer peripheral surface of the fixed dummy block 3a and the inner peripheral surface of the container liner 24 during independent retraction of the main ram after the container and main ram simultaneously retract. Therefore, as shown in FIG. 6(a), there is no increase, decrease, or fluctuation in the actual pressure P3 generated in the container cylinder.

[0047] Meanwhile, as described above, repeated extrusion processes cause the fixed dummy block 3a to expand, scratching its outer circumferential surface and causing the aluminum material of the billet B to adhere thereto. Furthermore, the inner circumferential surface of the container liner 24 is also scratched and the aluminum material of the billet B to adhere thereto. Therefore, after the container and main ram have simultaneously retracted, when the main ram independently retracts, the sliding resistance of the fixed dummy block 3a in the container liner 24 fluctuates. Figure 6(b) shows a waveform measured in a state in which the actual pressure P3 of the container cylinder 21, in which the supply and discharge of hydraulic oil has been stopped, has increased by dp3 (a fluctuation value) compared to the reference waveform due to this sliding resistance fluctuation. In the third embodiment, when the main ram independently retracts after the container and main ram have simultaneously retracted, such a waveform is measured in the fixed dummy block sliding waveform measurement process.

[0048] Then, a deterioration determination process is performed in which the waveform as shown in Fig. 6(b) measured in the fixed dummy block sliding waveform measurement process is compared with the reference waveform shown in Fig. 6(a). In the deterioration determination process, a preset allowable value of the actual pressure that is the allowable deviation from the reference waveform is compared with a fluctuation value for the reference waveform calculated from the measured actual waveform, and if, for example, the fluctuation value dp3 in Fig. 6(b) exceeds the corresponding allowable value, it is determined that at least one of the fixed dummy block 3a and the container liner 24 has deteriorated.

[0049] In this way, the method for determining deterioration of the fixed dummy block and container liner of an extrusion press apparatus includes a fixed dummy block sliding waveform measurement step for measuring the waveform of the actual pressure generated in the container cylinder, which is a hydraulic actuator, when the main ram independently retracts after the extrusion process, after the container strip operation, and after the container and main ram simultaneously retract, and a deterioration determination step for comparing the measured waveform with a reference waveform. This deterioration determination can be determined based on certain criteria. Furthermore, by notifying the operator of this deterioration determination via a display device or a sound generating device of the extrusion press apparatus, the fixed dummy block and container liner can be replaced at an appropriate time regardless of experience, thereby avoiding problems such as replacing still usable dummy blocks or delaying replacement that causes disruptions to the operation of the extrusion press apparatus.

[0050] The first to third embodiments have been described above as forms for implementing the invention, but it goes without saying that the present invention is not limited to the above-described embodiments and can be implemented in various forms without departing from the scope of the claims.

[0051] For example, in the first to third embodiments, the deterioration determination made in the deterioration determination step is notified to the operator by a display device or a voice generating device of the extrusion press. Here, the number of operations since the replacement of the fixed dummy block and the container liner or the cleanout of the container, at which the deterioration determination was made, may be stored as the number of deterioration determination operations and used to announce the deterioration determination to the operator.

[0052] Specifically, a deterioration alarm may be issued according to the stage from a predetermined number of times before the number of operations since replacement of the fixed dummy block and container liner or since container cleanout reaches the deterioration judgment operation number until the number of operations reaches the deterioration judgment operation number. For example, if a deterioration judgment is made when the number of operations since replacement of the fixed dummy block and container liner or since container cleanout was last performed is 50, 50 is stored as the deterioration judgment operation number in association with the extrusion conditions at that time (extrusion product and extrusion condition settings). Then, under the next same extrusion conditions, the first deterioration alarm is issued when the number of operations since replacement of the fixed dummy block and container liner or since container cleanout reached 40, prompting preparation for replacement of the fixed dummy block and container liner or container cleanout. Next, when the number of operations reaches 45, a second deterioration alarm is issued, indicating that there are 5 more operations until the previous number of operations for determining deterioration reaches 50, and finally, when the number of operations reaches 50, a third deterioration alarm is issued to announce that the previous number of operations for determining deterioration has been reached and that the fixed dummy block and container liner should be replaced and the container should be cleaned out, so that the deterioration alarm can be issued in stages.

[0053] Furthermore, in the first to third embodiments, the allowable values ​​(including the allowable variation range and allowable peak value) of the actual pressure and actual sliding speed that are set in advance and allowable to deviate from the reference waveform are preferably reviewed appropriately, such as by increasing or decreasing the values, after the deterioration judgment is made based on each numerical value, by visually checking the actual degree of deterioration of the fixed dummy block and container liner. [Explanation of symbols]

[0054] 1 container, 2 die, 3 extrusion stem, 3a fixed dummy block, 4 main cylinder, 4a main ram, 5 main pump unit, 10 end platen, 10a pressure ring, 21 container cylinder, 22 billet loader, 23 cylinder rod (side cylinder), 24 container liner, 25 discard, B Billet, W Aluminum products,

Claims

1. a fixed dummy block sliding waveform measuring step of measuring at least one of a waveform of an actual pressure generated in the hydraulic actuator and a waveform of an actual sliding speed of the hydraulic actuator when the fixed dummy block slides; a deterioration determination step of comparing at least one of the waveform of the actual pressure generated in the hydraulic actuator and the waveform of the actual sliding speed of the hydraulic actuator, which are measured in the fixed dummy block sliding waveform measurement step, with a corresponding preset reference waveform, A method for determining deterioration of a fixed dummy block and a container liner of an extrusion press apparatus, characterized in that in the deterioration determination step, if at least one of the waveform of the actual pressure generated in the hydraulic actuator and the waveform of the actual sliding speed of the hydraulic actuator measured in the fixed dummy block sliding waveform measurement step exceeds a predetermined allowable value from the corresponding reference waveform, it is determined that at least one of the fixed dummy block and the container liner is deteriorated.

2. 2. The method for determining deterioration of a fixed dummy block and a container liner of an extrusion press apparatus according to claim 1, wherein the reference waveform is at least one of a waveform of the actual pressure generated in the hydraulic actuator and a waveform of the actual sliding speed of the hydraulic actuator when the fixed dummy block slides after the fixed dummy block and the container liner are replaced or after a cleanout of the container is performed.

3. 3. The method for determining deterioration of a fixed dummy block and a container liner of an extrusion press apparatus according to claim 1 or 2, wherein the sliding of the fixed dummy block occurs when the fixed dummy block inserts a billet into the container using an extrusion stem attached to the front end of the fixed dummy block, and the hydraulic actuator is a side cylinder.

4. 4. The method for determining deterioration of a fixed dummy block and a container liner of an extrusion press apparatus according to claim 3, characterized in that if the waveform of the actual pressure generated in the side cylinder exceeds the preset allowable value from the initial stage when the fixed dummy block is inserted into the container liner when the billet is inserted into the container, based on the corresponding reference waveform, it is determined that the fixed dummy block is deteriorated.

5. 3. The method for determining deterioration of a fixed dummy block and a container liner of an extrusion press apparatus according to claim 1 or 2, characterized in that the sliding of the fixed dummy block occurs when the main ram retreats alone after the extrusion process, after the container strip operation, and after the container and main ram have simultaneously retreated, and the hydraulic actuator is a side cylinder that retreats the main ram.

6. 3. The method for determining deterioration of a fixed dummy block and a container liner of an extrusion press apparatus according to claim 1 or 2, characterized in that the sliding of the fixed dummy block occurs when the main ram retreats alone after the extrusion process, after the container strip operation, and after the container and main ram have simultaneously retreated, and the hydraulic actuator is a container cylinder in which the supply and discharge of hydraulic oil has been stopped.

7. 7. The method for determining deterioration of a fixed dummy block and a container liner of an extrusion press apparatus according to claim 1, wherein the number of operations since replacement of the fixed dummy block and the container liner or since cleanout of the container, when a determination of deterioration of the fixed dummy block and the container liner has been made in the deterioration determination step, is stored as a deterioration determination operation count, and a deterioration alarm is issued according to a stage from a predetermined number of times before the number of operations since the next replacement of the fixed dummy block and the container liner or since cleanout of the container reaches the deterioration determination operation count until the number of operations reaches the deterioration determination operation count.

Images