Method for detecting glue permeation condition of open type steel cord

Abstract

The invention discloses a method for detecting the rubber permeation condition of an open type steel cord, which is used for accurately reflecting the rubber permeation condition of the steel cord in the rolling process and simulating the rolling process of a rubber sheet and the open type cord in a test, and the steel cord is vulcanized together with the rubber sheet after tension is applied to the steel cord. Meanwhile, performing hot inlaying, grinding and polishing treatment on the sample by adopting red inlaying powder to obtain a clear cross section, and observing the rubber permeation condition under a microscope. And finally, covering a metallograph or a microscopic visual field with standard grid transparent paper, counting the total grid number and the rubber permeation grid number, and calculating the rubber permeation rate. Compared with the prior art, the method not only effectively simulates the rubber permeation behavior during rolling of the open type steel cord and the rubber, but also can clearly display and quantify the rubber distribution condition of the rubber in the open type steel cord, and provides a reliable basis for process optimization.

Description

Technical Field

[0001] The present invention relates to the technical field of steel cord detection, and in particular to a method for detecting glue penetration of an open steel cord. Background Art

[0002] Steel cord is widely used in rubber products such as tires and conveyor belts. Its adhesion performance with rubber directly affects the service life and safety of the product.

[0003] Open steel cord features periodic gaps between filaments, a characteristic that makes rubber more easily penetrated. However, during the calendering of rubber products with open steel cord, the cord is often subjected to payout tension, which reduces the gaps between the cords. Traditional rubber penetration testing methods cannot accurately assess the effect of payout tension on the rubber penetration of open steel cord. Furthermore, it is difficult to clearly observe the penetration of black rubber into different layers of open steel cord, making it difficult to provide effective guidance for process adjustments.

[0004] Therefore, a detection method that can truly reflect the glue penetration of open steel cord is needed. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for detecting the glue penetration of an open steel cord, which not only simulates the glue penetration of the open steel cord when it is rolled together with rubber, but also can clearly display and calculate the glue penetration of rubber in different layers of the open steel cord, providing a reliable basis for process optimization to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions: A method for detecting glue penetration of an open steel cord comprises the following steps: Step 1: Melt the open steel cord to be tested into standard length and lock the two ends of the steel cord with lock buckles. At the same time, prepare two rubber sheets of the same size.

[0007] Step 2: Place the steel cord with the lock buckle into the groove of the vulcanizer matching mold, so that the lock buckle at one end is stuck in the notch at one end of the mold groove, and hang a hook weight of a certain mass on the other end of the steel cord. Two rubber sheets of the same size are placed in the groove, and the steel cord passes between the two rubber sheets to simulate the vulcanization process of the rubber sheet and the open steel cord during the calendering process. Then, the open steel cord and the rubber sheet are vulcanized together according to the vulcanization temperature, pressure and time of the rubber sheet.

[0008] Step 3: After vulcanization is completed, quickly remove the mold and demould the sample, and place it at room temperature for more than 16 hours.

[0009] Step 4: Trim the rubberized steel cord sample prepared above, hot-mount the trimmed sample twice using colored mounting powder, and then grind and polish it until a complete and clear cross-sectional image is revealed.

[0010] Step 5: Observe the rubber penetration into the steel cord under a stereo microscope and take photos.

[0011] Step 6: Use transparent paper with standard-sized grids to cover the metallographic photograph or microscope field of view, and calculate the ratio of the total number of grids covered in the steel cord section to the number of grids covered in the rubber penetration area to obtain the rubber penetration rate.

[0012] A further improvement of the present invention is that the mold is a rectangular block, and the groove is set on the front of the mold; the groove includes a rectangular block groove located in the middle of the mold, the upper and lower ends of the block groove are connected to the wire groove, and the two wire grooves extend to both ends of the mold.

[0013] A further improvement of the present invention is that the lock buckle is cylindrical and locks the two ends of the steel cord to form a buckle; the steel cord passes through the wire groove and the embedment groove, the top lock block is clamped to the top of the mold, and the weight is hung on the bottom buckle.

[0014] A further improved solution of the present invention is that the rubber sheet is accommodated in the insert groove, the steel cord passes between the two rubber sheets, and the steel cord is in contact with the two rubber sheets.

[0015] A further improvement of the present invention is that in step 2, the vulcanization temperature is 140-180° C., the vulcanization pressure is 0-40 MPa, and the vulcanization time is 10-80 min.

[0016] Beneficial effects of the present invention: The method for detecting the glue seepage of the open steel cord of the present invention simulates the situation when the rubber product and the steel cord are calendered during the test process, applies tension to the cord and then vulcanizes it together with the rubber, which can accurately reflect the glue seepage of the open steel cord during the rubber calendering process.

[0017] The method for detecting the rubber penetration of an open steel cord of the present invention uses red inlay powder to perform hot inlaying twice, followed by grinding and polishing to obtain a clear cross-section, in order to more clearly see the distribution of rubber in the steel cord. The distribution of rubber in the open steel cord is then observed under a microscope.

[0018] The method for detecting the adhesive penetration of an open steel cord of the present invention uses transparent paper with standard-sized grids to cover a metallographic photograph or a microscope field, counts the total number of grids covered in the steel cord section and the number of grids covered in the rubber penetration area, and calculates the adhesive penetration rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the structure in which both ends of the steel cord of the present invention are locked with lock buckles.

[0020] Figure 2 This is a schematic structural diagram of the mold supporting the vulcanizer of the present invention.

[0021] Figure 3 This is a schematic structural diagram of the steel cord passing through a die according to the present invention.

[0022] Figure 4 This is a diagram showing the position relationship between the steel cord and the rubber sheet of the present invention.

[0023] Figure 5 Schematic diagram of the adhesive penetration of 3×0.30 OC HT steel cord in Example 1.

[0024] Figure 6 Schematic diagram of the adhesive penetration of 4×0.225 OC UT steel cord in Example 2.

[0025] Figure 7 Schematic diagram of the adhesive penetration of 5×0.225 OC UT steel cord in Example 3.

[0026] In the figure: 1- steel cord, 2- lock buckle, 3- rubber sheet, 4- mold, 401- block groove, 402- wire groove, 5- weight. DETAILED DESCRIPTION

[0027] The present invention will be further explained below with reference to the accompanying drawings and specific embodiments. Example 1

[0028] Step 1: Cut open steel cord 3×0.30 OC HT into 1.8~2.0m, and Figure 1 As shown, the cord is locked with wire lock buckles 2 at 0.6m and 0.4m at both ends. At the same time, two rubber sheets 3 with a length and width of 16.5mm×1.25mm and a weight of 4.5-5.5g need to be prepared.

[0029] Step 2: Figure 2 、 3 As shown in Figure 4, tear off the polyethylene films on both sides of the rubber sheet 3, place it into the mold 4 with the smooth side facing up, place the open steel cord 3×0.30 OC HT equipped with the lock buckle 2 into the groove of the mold 4, make the lock buckle 2 at one end of the steel cord 1 stuck in the groove of the mold 4, and hang a 1000g hook weight 5 on one end of the steel cord 1, then vulcanize the steel cord 1 sample and the rubber sheet 3 together, and the vulcanization conditions are 151℃×40min×15MPa.

[0030] Step 3: After vulcanization is completed, quickly remove the mold 4 and demould the sample, and place it at room temperature for more than 16 hours.

[0031] Step 4: Trim the rubber-coated steel cord 1 sample prepared above, perform two hot-mounting operations on the trimmed sample, and then grind and polish it until a complete and clear cross-sectional image is revealed.

[0032] Step 5: Observe the rubber seepage in the steel cord 1 under a 50x stereo microscope and take photos. The results are as follows: Figure 5 shown.

[0033] Step 6. Use 1mm×1mm transparent paper with standard size grids to cover the metallographic photograph and calculate the ratio of the number of grids covered in the rubber penetration area to the total number of grids covered in the cross section of the steel cord 1. The result shows that the rubber penetration rate of the open steel cord 3×0.30OC HT under the tension caused by the 1000g weight 5 is 98.42%. Example 2

[0034] Step 1: Melt the open steel cord 4×0.225 OC UT into 1.8~2.0m, and Figure 1 As shown, the cord is locked with wire lock buckles 2 at 0.6m and 0.4m at both ends. At the same time, two rubber sheets 3 with a length and width of 16.5mm×1.25mm and a weight of 4.5-5.5g need to be prepared.

[0035] Step 2: Figure 2 、 3 As shown in Figure 4, tear off the polyethylene film on both sides of the rubber sheet 3, place it into the mold 4 with the smooth side facing up, place the open steel cord 4×0.225 OC UT equipped with the lock buckle 2 into the groove of the mold 4, make the lock buckle 2 at one end of the steel cord 1 stuck in the groove of the mold 4, and hang a 1000g hook weight 5 on the other end of the steel cord 1, and then vulcanize the steel cord 1 sample and the rubber sheet 3 together. The vulcanization conditions are 151℃×40min×15MPa.

[0036] Step 3: After vulcanization is completed, quickly remove the mold 4 and demould the sample, and place it at room temperature for more than 16 hours.

[0037] Step 4: Trim the rubber-coated steel cord 1 sample prepared above, perform two hot-mounting operations on the trimmed sample, and then grind and polish it until a complete and clear cross-sectional image of the sample is revealed.

[0038] Step 5: Observe the rubber seepage in the steel cord 1 under a 50x stereo microscope and take photos. The results are as follows: Figure 6 shown.

[0039] Step 6. Use 1mm×1mm transparent paper with standard size grids to cover the metallographic photograph and calculate the ratio of the number of grids covered in the rubber penetration area to the total number of grids covered in the cross section of the steel cord 1. The result shows that the rubber penetration rate of the open steel cord 4×0.225OC UT under the tension brought by the 1000g weight 5 is 79.32%. Example 3

[0040] Step 1: Melt the open steel cord 5×0.225 OC UT into 1.8~2.0m, and Figure 1 As shown, the cord is locked with wire lock buckles 2 at 0.6m and 0.4m at both ends. At the same time, two rubber sheets 3 with a length and width of 16.5mm×1.25mm and a weight of 4.5-5.5g need to be prepared.

[0041] Step 2: Figure 2 、 3 As shown in Figure 4, tear off the polyethylene film on both sides of the rubber sheet 3, place it into the mold 4 with the smooth side facing up, place the open steel cord 5×0.225 OC UT equipped with the lock buckle 2 into the groove of the mold 4, make the lock buckle 2 at one end of the steel cord 1 stuck in the groove of the mold 4, and hang an 800g hook weight 5 on the other end of the steel cord 1, then vulcanize the steel cord 1 sample and the rubber sheet 3 together, and the vulcanization conditions are 151℃×40min×15MPa.

[0042] Step 3: After vulcanization is completed, quickly remove the mold 4 and demould the sample, and place it at room temperature for more than 16 hours.

[0043] Step 4: Trim the rubber-coated steel cord 1 sample prepared above, perform two hot-mounting operations on the trimmed sample, and then grind and polish it until a complete and clear cross-sectional image of the sample is revealed.

[0044] Step 5: Observe the rubber seepage in the steel cord 1 under a 50x stereo microscope and take photos. The results are as follows: Figure 7 shown.

[0045] Step 6. Use 1mm×1mm transparent paper with standard size grids to cover the metallographic photograph and calculate the ratio of the number of grids covered in the rubber penetration area to the total number of grids covered in the cross section of the steel cord 1. The result shows that the rubber penetration rate of the open steel cord 5×0.225OC UT under the tension brought by the 800g weight 5 is 80.11%.

[0046] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made in accordance with the spirit of the present invention are intended to be covered by the scope of protection of the present invention.

Claims

1. A method for detecting glue penetration of an open steel cord, characterized in that: The steps include: Step 1: Melt the open steel cord (1) to be tested into a standard length and lock the two ends of the steel cord (1) with lock buckles (2). At the same time, prepare two rubber sheets (3) of the same size; Step 2: Place the steel cord (1) equipped with the lock buckle (2) into the groove of the matching mold (4) of the vulcanizer, so that the lock buckle (2) at one end is stuck in the notch at one end of the groove of the mold (4), and hang a hook weight (5) of a certain mass on the other end of the steel cord (1). Two rubber sheets (3) of the same size are placed in the groove, and the steel cord (1) passes between the two rubber sheets (3) to simulate the vulcanization process of the rubber sheet (3) and the open steel cord (1) during the calendering process. Then, the open steel cord (1) and the rubber sheet (3) are vulcanized together according to the vulcanization temperature, pressure and time of the rubber sheet (3); Step 3: After the vulcanization is completed, the mold (4) is quickly removed and the sample is demoulded and placed at room temperature for more than 16 hours; Step 4: Trim the rubber-coated steel cord (1) sample prepared above, heat-mount the trimmed sample twice using colored mounting powder, and then grind and polish it until a complete and clear cross-sectional image is revealed; Step 5: Observe the rubber penetration into the steel cord (1) under a stereo microscope and take photos; Step 6: Use a transparent paper with a standard size grid to cover the metallographic photograph or the microscope field of view, and calculate the ratio of the total number of grids covered in the steel cord (1) section to the number of grids covered in the rubber penetration area to obtain the rubber penetration rate.

2. The method for detecting adhesive penetration of an open steel cord according to claim 1, wherein: The mold (4) is in the shape of a rectangular block, and a groove is provided on the front face of the mold (4); the groove comprises a rectangular insert groove (401) located in the middle of the mold (4), the upper and lower ends of the insert groove (401) are connected to the wire groove (402), and the two wire grooves (402) extend to the two ends of the mold (4).

3. The method for detecting adhesive penetration of an open steel cord according to claim 2, wherein: The lock buckle (2) is cylindrical and locks the two ends of the steel cord (1) to form a ring buckle; the steel cord (1) passes through the wire groove (402) and the block groove (401), the top locking block is clamped to the top of the mold (4), and the weight (5) is hung on the ring buckle at the bottom.

4. A method for detecting adhesive penetration of an open steel cord according to claim 2 or 3, characterized in that: The rubber sheet (3) is accommodated in the insert groove (401), the steel cord (1) passes between the two rubber sheets (3), and the steel cord (1) is in contact with the two rubber sheets (3).

5. The method for detecting adhesive penetration of an open steel cord according to claim 1, wherein: In the step 2, the vulcanization temperature is 140-180° C., the vulcanization pressure is 0-40 MPa, and the vulcanization time is 10-80 min.

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