Preparation method of steel wire rope for testing

Abstract

The invention discloses a preparation method of a steel wire rope for testing. The preparation method is specifically implemented according to the following steps: step 1, preparing a lead-bismuth alloy; 2, a steel wire rope with the length not smaller than 1 m is cut out; step 3, removing the head of the cut steel wire rope; 4, grease on the detached rope head is cleaned, and moisture is removed in an air-drying mode; and 5, the lead bismuth alloy is used for casting the rope head. According to the preparation method of the steel wire rope for testing, the steel wire rope head can be manufactured by a hot casting method, the reliable consolidation of a casting material to the steel wire rope is ensured, the casting temperature is effectively reduced to 200 DEG C or below, the influence of the thermal action on the performance of the steel wire rope is eliminated, the casting material can be more efficiently recycled, and the energy consumption is effectively reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of alloy products and relates to a method for preparing a steel wire rope for testing. Background Art

[0002] The breaking test of wire rope is an important means to test the mechanical properties of wire rope. At present, the industry mainly adopts hot casting method to make wire rope heads. After connecting and fixing them with tooling that adapts to the shape, the breaking tension of the wire rope is measured. The casting materials are mainly zinc and its alloys, but the melting point of zinc and its alloys is above 400℃, which will have a thermal effect on the wire rope and reduce its performance, resulting in the test results being unable to truly reflect the performance level of the wire rope. In addition, the high casting temperature also increases energy consumption, reduces production efficiency, and also puts operators at a greater risk of scalding. In addition, the rope heads cast with zinc and its alloys are difficult to peel off from the surface of the steel wire due to the alloy reaction between zinc and iron, and can no longer be recycled. They can only be treated as waste, resulting in serious material waste. The melting points of other used casting materials are all above 250℃, and the actual casting temperature is above 300℃. In a few cases, cold casting with epoxy resin as casting material is also used, but the cost of this method is dozens of times that of hot casting, and it cannot be promoted and applied for a long time. Relevant studies have shown that when the temperature drops below 200°C, the influence of thermal effects on the mechanical properties of steel materials can be basically eliminated. Therefore, a new casting material that can meet the casting requirements below 200°C and save test costs is of great value and significance to the development of wire rope breaking tests. Summary of the invention

[0003] The purpose of the present invention is to provide a method for preparing a steel wire rope for testing, which solves the problem in the existing steel wire rope head production that the casting material has a thermal effect on the steel wire rope, thereby reducing its performance.

[0004] The technical solution adopted by the present invention is a method for preparing a test steel wire rope, which is specifically implemented according to the following steps:

[0005] Step 1, preparing a lead-bismuth alloy;

[0006] Step 2: Cut a wire rope of no less than 1m;

[0007] Step 3, dismantle the cut wire rope;

[0008] Step 4: Clean the grease on the disassembled rope head and dry it;

[0009] Step 5: Use lead-bismuth alloy to cast the rope head.

[0010] The present invention is also characterized in that:

[0011] The specific steps of preparing the lead-bismuth alloy in step 1 are:

[0012] Step 1.1, add an appropriate amount of metal lead into the crucible, then add a covering agent, the covering agent covers the metal lead, and set the furnace temperature to 330℃-430℃;

[0013] Step 1.2, after all the metal lead is melted, add 44%-68% of metal bismuth by weight, and set the furnace temperature to 330°C-430°C;

[0014] Step 1.3, after all the bismuth metal is melted, set the furnace temperature to 150°C-200°C, stir the alloy liquid for 0.5min-1min every 8min-15min, and stir for no less than 2 times;

[0015] Step 1.4: The temperature of the alloy liquid is reduced to 150°C-200°C, and the preparation of the lead-bismuth alloy is completed.

[0016] The specific method of removing the head in step 3 is: leave 160mm~300mm at both ends of the cut wire rope, tie it with wire at 160mm~300mm away from the end, and disassemble the remaining section of the wire rope into a broom shape.

[0017] The specific steps of casting the rope head in step 5 are:

[0018] 5.1. Place the cleaned broom-shaped rope head in step 4 into the conical casting mold;

[0019] 5.2. Correct the rope position;

[0020] 5.3. Cast the lead-bismuth alloy prepared in step 1 into a mold and solidify it so that it is consolidated with the steel wire rope sample to form a conical casting head.

[0021] In step 1.1, the covering agent is charcoal powder or liquid lead antioxidant inhibitor.

[0022] The beneficial effects of the present invention are:

[0023] The present invention provides a method for preparing a steel wire rope for testing. When a steel wire rope head is made by hot casting, reliable consolidation of the casting material to the steel wire rope is ensured, and the casting temperature is effectively reduced to below 200°C, eliminating the influence of heat on the performance of the steel wire rope. At the same time, the casting material can be more efficiently recycled and reused than zinc and zinc alloys, effectively reducing energy consumption, greatly reducing test waste, and reducing test costs. DETAILED DESCRIPTION

[0024] The present invention is described in detail below in conjunction with specific implementation modes.

[0025] The present invention provides a method for preparing a steel wire rope for testing, which is specifically implemented according to the following steps:

[0026] Step 1, preparing a lead-bismuth alloy;

[0027] Step 1.1, add an appropriate amount of metallic lead into the crucible, then add charcoal powder or liquid lead antioxidant inhibitor, until the charcoal powder or liquid lead antioxidant inhibitor covers the metallic lead, and set the furnace temperature to 330℃-430℃;

[0028] Step 1.2, after all the metal lead is melted, add 44%-68% of metal bismuth by weight, and set the furnace temperature to 330°C-430°C;

[0029] Step 1.3, after all the bismuth metal is melted, set the furnace temperature to 150°C-200°C, stir the alloy liquid for 0.5min-1min every 8min-15min, and stir for no less than 2 times;

[0030] Step 1.4: The temperature of the alloy liquid is reduced to 150°C-200°C, and the preparation of the lead-bismuth alloy is completed.

[0031] Step 2: Cut a wire rope of no less than 1m;

[0032] Step 3, dismantle the cut wire rope;

[0033] Leave 160mm~300mm at both ends of the cut wire rope, tie it with wire at 160mm~300mm away from the end, and disassemble the remaining section of the wire rope into a broom shape.

[0034] Step 4: Clean the grease on the disassembled rope head and dry it;

[0035] Step 5, casting the rope head;

[0036] 5.1. Place the cleaned broom-shaped rope head in step 4 into the conical casting mold;

[0037] 5.2. Correct the rope position;

[0038] 5.3. Cast the lead-bismuth alloy prepared in step 1 into a mold and solidify it so that it is consolidated with the steel wire rope sample to form a conical casting head.

[0039] Preferably, in the above method, the mass proportion of metallic bismuth in the lead-bismuth alloy is 55.5%.

[0040] Preferably, in the above method, the angle of the outermost wire of the broom-shaped disassembled section of the wire rope is 55°±5°.

[0041] Preferably, in the above method, the cone angle of the conical casting head is 18° to 32°.

[0042] Example 1

[0043] The preparation method of the test wire rope proposed in this embodiment is specifically implemented according to the following steps:

[0044] Step 1, preparing a lead-bismuth alloy;

[0045] Step 1.1, add 44.5kg of metallic lead into the crucible, then add charcoal powder until the charcoal powder covers the metallic lead, and set the furnace temperature to 330℃;

[0046] Step 1.2, after all the lead metal is melted, add 55.5 kg of bismuth metal and set the furnace temperature to 330°C;

[0047] Step 1.3, after all the bismuth metal is melted, set the furnace temperature to 150°C, stir the alloy liquid for 0.5 min every 8 min, and stir twice;

[0048] Step 1.4: The temperature of the alloy liquid is reduced to 150°C, and the preparation of the lead-bismuth alloy is completed.

[0049] Step 2: Cut 1m long wire rope;

[0050] Step 3, dismantle the cut wire rope;

[0051] Leave 160mm at both ends of the cut wire rope, tie it with wire 160mm away from the end, and disassemble the remaining section of the wire rope into a broom shape, with the angle of the outermost wire of the disassembled section being 50°.

[0052] Step 4: Clean the grease on the disassembled rope head and dry it;

[0053] Step 5, casting the rope head;

[0054] 5.1. Place the cleaned broom-shaped rope head in step 4 into a conical casting mold with a mold cone angle of 18°;

[0055] 5.2. Correct the rope position;

[0056] 5.3. Cast the lead-bismuth alloy prepared in step 1 into a mold and solidify it so that it is consolidated with the steel wire rope sample to form a conical casting head.

[0057] Step 6: Perform a breaking test and record the tensile force value at breaking;

[0058] Step 7: After the test is completed, place the conical casting head into the crucible to re-melt the casting material, separate it from the wire rope sample, and recycle the casting material for reuse.

[0059] Example 2

[0060] The preparation method of the test wire rope proposed in this embodiment is specifically implemented according to the following steps:

[0061] Step 1, preparing a lead-bismuth alloy;

[0062] Step 1.1, add 32kg of metallic lead into the crucible, then add charcoal powder until the charcoal powder covers the metallic lead, and set the furnace temperature to 400℃;

[0063] Step 1.2, after all the lead metal is melted, add 68 kg of bismuth metal and set the furnace temperature to 400°C;

[0064] Step 1.3, after all the bismuth metal is melted, set the furnace temperature to 180°C, stir the alloy liquid for 0.8 min every 10 min, and stir 3 times;

[0065] Step 1.4: The temperature of the alloy liquid is reduced to 180°C, and the preparation of the lead-bismuth alloy is completed.

[0066] Step 2: Cut a 2m long wire rope;

[0067] Step 3, dismantle the cut wire rope;

[0068] Leave 230mm at both ends of the cut wire rope, tie it with wire 230mm away from the end, and disassemble the remaining section of the wire rope into a broom shape, with the angle of the outermost wire of the disassembled section being 55°.

[0069] Step 4: Clean the grease on the disassembled rope head and dry it;

[0070] Step 5, casting the rope head;

[0071] 5.1. Place the cleaned broom-shaped rope head in step 4 into a conical casting mold with a mold cone angle of 24°;

[0072] 5.2. Correct the rope position;

[0073] 5.3. Cast the lead-bismuth alloy prepared in step 1 into a mold and solidify it so that it is consolidated with the steel wire rope sample to form a conical casting head.

[0074] Step 6: Perform a breaking test and record the tensile force value at breaking;

[0075] Step 7: After the test is completed, place the conical casting head into the crucible to re-melt the casting material, separate it from the wire rope sample, and recycle the casting material for reuse.

[0076] Example 3

[0077] The preparation method of the test wire rope proposed in this embodiment is specifically implemented according to the following steps:

[0078] Step 1, preparing a lead-bismuth alloy;

[0079] Step 1.1, add 56 kg of metallic lead into a crucible, then add liquid lead antioxidant inhibitor, until the liquid lead antioxidant inhibitor covers the metallic lead, and set the furnace temperature to 430°C;

[0080] Step 1.2, after all the lead metal is melted, add 44 kg of bismuth metal and set the furnace temperature to 430°C;

[0081] Step 1.3, after all the bismuth metal is melted, set the furnace temperature to 200°C, stir the alloy liquid for 1 minute every 15 minutes, and stir 4 times;

[0082] Step 1.4: The temperature of the alloy liquid is reduced to 200°C, and the preparation of the lead-bismuth alloy is completed.

[0083] Step 2: Cut 3m long wire rope;

[0084] Step 3, dismantle the cut wire rope;

[0085] Leave 300mm at both ends of the cut wire rope, tie it with wire 300mm away from the end, and disassemble the remaining section of the wire rope into a broom shape, with the angle of the outermost wire of the disassembled section being 60°.

[0086] Step 4: Clean the grease on the disassembled rope head and dry it;

[0087] Step 5, casting the rope head;

[0088] 5.1. Place the cleaned broom-shaped rope head in step 4 into a conical casting mold with a mold cone angle of 32°;

[0089] 5.2. Correct the rope position;

[0090] 5.3. Cast the lead-bismuth alloy prepared in step 1 into a mold and solidify it so that it is consolidated with the steel wire rope sample to form a conical casting head.

[0091] Step 6: Perform a breaking test and record the tensile force value at breaking;

[0092] Step 7: After the test is completed, place the conical casting head into the crucible to re-melt the casting material, separate it from the wire rope sample, and recycle the casting material for reuse.

[0093] Comparative Example

[0094] This comparative example uses zinc metal as a casting material in a steel wire rope breaking test, and is specifically implemented in the following steps:

[0095] Step 1, melting of metallic zinc;

[0096] Step 1.1, add 110kg of metallic zinc into the crucible, then add charcoal powder, until the charcoal powder covers the metallic lead, and set the furnace temperature to 480℃;

[0097] Step 1.2: After all the zinc metal is melted, set the furnace temperature to 480°C, stir the molten metal for 0.5min to 1min, stir 2-3 times, and maintain the furnace temperature until the zinc metal is completely melted.

[0098] Step 2: Cut a 1.8m long wire rope;

[0099] Step 3, dismantle the cut wire rope;

[0100] Leave 180mm at both ends of the cut wire rope, tie it with wire 180mm away from the end, and disassemble the remaining section of the wire rope into a broom shape, with the angle of the outermost wire of the disassembled section being 55°.

[0101] Step 4: Clean the grease on the disassembled rope head and dry it;

[0102] Step 5, casting the rope head;

[0103] 5.1. Place the cleaned broom-shaped rope head in step 4 into a conical casting mold with a mold cone angle of 22.38°;

[0104] 5.2. Correct the rope position;

[0105] 5.3. Pour the molten zinc metal in step 1 into the mold and solidify it so that it is consolidated with the steel wire rope sample to form a conical casting head.

[0106] Step 6: Perform a breaking test and record the tensile force value at breaking;

[0107] Step 7: After the test is completed, place the conical casting head into the crucible to re-melt the casting material, separate it from the wire rope sample, and recycle the casting material for reuse.

[0108] The test results of each embodiment and comparative example are shown in Table 1:

[0109] Table 1 Test results of various embodiments and comparative examples

[0110]

[0111]

[0112] The methods for obtaining the test results in the table are as follows:

[0113] (1) Breaking force value: directly read by performing a wire rope breaking test on a tensile testing machine;

[0114] (2) Casting temperature: Use a thermocouple to directly measure and read the actual temperature of the molten metal during the casting operation;

[0115] (3) Surface condition of steel wire after remelting: remelt the conical casting head after the test to separate the casting material from the wire rope sample, and observe the adhesion of the residual casting material on the surface of the steel wire of the broom-shaped rope head;

[0116] (4) Heating time: Use a timer to record the time required for the casting material to completely melt from solid to liquid;

[0117] (5) Alloy loss: The weight of the wire rope sample before casting and after remelting is compared by weighing with an electronic scale. The difference between the two is the alloy loss for a breaking test.

[0118] As can be seen from Table 1, Examples 1, 2, and 3 all successfully completed the breaking test of the steel wire rope, and the breaking tensile values ​​of the three are basically similar, which is 19.7% higher than the control example on average, indicating that the lead-bismuth alloy can successfully complete the casting operation at a casting temperature of 180° C., and can not only reliably consolidate the steel wire rope, but also effectively eliminate the influence of thermal effects on the performance of the steel wire rope.

[0119] In addition, after the casting head is melted back, there is no obvious adhesion of lead-bismuth alloy on the surface of the steel wire in Examples 1, 2 and 3, while a large amount of zinc is adhered to the surface of the steel wire in the comparative example, indicating that the melt-back rate of lead-bismuth alloy is higher. After calculating the alloy loss, the lead-bismuth alloy is 14.1% of zinc on average, which greatly reduces the waste of casting materials. At the same time, the time required for the complete melting of the lead-bismuth alloy is shorter, and the furnace temperature is set lower, which effectively saves energy consumption and reduces the test cost.

Claims

1. A method for preparing a test steel wire rope, characterized in that: Follow the steps below to implement it: Step 1, preparing a lead-bismuth alloy; Step 2: Cut a wire rope of no less than 1m; Step 3, dismantle the cut wire rope; Step 4: Clean the grease on the disassembled rope head and dry it; Step 5: Use lead-bismuth alloy to cast the rope head.

2. The method for preparing a test steel wire rope according to claim 1, characterized in that: The specific steps of preparing the lead-bismuth alloy are: Step 1.1, add an appropriate amount of metal lead into the crucible, then add a covering agent, the covering agent covers the metal lead, and set the furnace temperature to 330℃-430℃; Step 1.2, after all the metal lead is melted, add 44%-68% of metal bismuth by weight, and set the furnace temperature to 330°C-430°C; Step 1.3, after all the bismuth metal is melted, set the furnace temperature to 150°C-200°C, stir the alloy liquid for 0.5min-1min every 8min-15min, and stir for no less than 2 times; Step 1.4: The temperature of the alloy liquid is reduced to 150°C-200°C, and the preparation of the lead-bismuth alloy is completed.

3. The method for preparing a test steel wire rope according to claim 1, characterized in that: The specific method of removing the head is: leaving 160mm to 300mm at each end of the cut wire rope, tying them with iron wire at a distance of 160mm to 300mm from the end, and dismantling the remaining wire rope into a broom shape.

4. The method for preparing a test steel wire rope according to claim 1, characterized in that: The specific steps of casting the rope head are: Step 5.1, put the broom-shaped rope head cleaned in step 4 into the conical casting mold; Step 5.2, calibrate the rope position; Step 5.3: Cast the lead-bismuth alloy prepared in step 1 into a mold and solidify it so that it is consolidated with the steel wire rope sample to form a conical casting head.

5. The method for preparing a test steel wire rope according to claim 2, characterized in that: The covering agent is charcoal powder or liquid lead antioxidant inhibitor.

Images