Needle latch steel wire production process

Abstract

The invention relates to the field of knitting needle processing, and discloses a needle latch steel wire production process which comprises the following steps: pickling and phosphating raw materials, and coating a phosphating film on the surface of a steel wire through hydrochloric acid pickling; drawing a semi-finished product: drawing the pickled and phosphatized wire rod to the specification of the semi-finished product through a straight wire drawing machine, and carrying out heat treatment after drawing each time; recrystallization annealing is conducted, work hardening generated in the drawing process is eliminated through low-temperature recrystallization annealing, deep processing continues in the later period, and the whole annealing process is replaced; carrying out surface treatment on the semi-finished product to remove a slight decarburized layer on the surface of the semi-finished product; water tank drawing: adopting a water tank drawing process on the last semi-finished product; finishing: after annealing the semi-finished product, obtaining the dimensional tolerance of the finished product through a finishing procedure, and meanwhile, improving the cleanliness of the surface of the steel wire; straightening: straightening the needle latch steel wire through a straightening process; the shunting frequency is reduced, the working efficiency is improved, the stress uniformity of the steel wire during rolling is improved, and the rolled steel wire is uniform in size.

Description

Technical Field

[0001] The invention relates to the field of knitting needle processing, in particular to a production process for needle latch steel wires. Background Art

[0002] like Figure 1 The needle latch steel wire shown in the figure usually has a production process that includes multiple steps. The traditional production process is: annealing wire → pickling and phosphating → wire drawing → recrystallization annealing → pickling and phosphating → wire drawing. The needle latch steel wire manufactured by the traditional production process is "loop-shaped" and cannot produce steel wire with good straightness. The finished products produced by the traditional process require time-consuming adjustment during the subsequent finished product processing, and the production efficiency is low.

[0003] In the document CN 115198180A, a method for producing refined wire for socket wrenches is disclosed, which includes pickling and phosphating, rough drawing, annealing, yellowing, secondary pickling and phosphating, and fine drawing. In the pickling and phosphating process, the Widmanstatten structure of the hot-rolled wire used should be level 0 or level 1, and the diameter should be 38-40 mm. In the yellowing process, the annealed wire is soaked in 8-16% hydrochloric acid for 5-10 minutes, and then placed outdoors for 24-48 hours. In this method, when manufacturing steel wire, since the steel wire is not straightened at the end, if it is made into a needle tongue, it is easy for the steel wire to be unevenly stressed when rolling, and the needle tongue finally made is easy to break when in use, and it often needs to be adjusted, which is troublesome.

[0004] Therefore, a new technical solution is needed to solve the above technical problems. Summary of the invention

[0005] In order to solve the above problems, the present invention discloses a needle tongue steel wire production process, which reduces the frequency of shunting, improves work efficiency, and improves the force uniformity of the steel wire during rolling, so that the size of the rolled steel wire is more uniform.

[0006] The technical solution of the present invention is: a needle latch steel wire production process, comprising the following steps:

[0007] Step 1: The raw materials are pickled and phosphated, and a phosphating film is applied on the surface of the steel wire by pickling with hydrochloric acid;

[0008] Step a: Acidification, achieved by low concentration hydrochloric acid;

[0009] Step b: primary water washing, the residual acid on the surface of the wire is washed clean by high-pressure water;

[0010] By adopting the above technical solution, since some hydrochloric acid will remain on the surface of the wire after pickling, in order to avoid the influence of the residual hydrochloric acid on the subsequent process, an additional water washing step can remove the residual hydrochloric acid on the surface of the wire;

[0011] Step c: Surface adjustment, by adding a surface adjuster into a medium-temperature water pool, and the surface adjuster solution is controlled by the pH index;

[0012] By adopting the above technical solution, the surface pretreatment effect before phosphating is achieved, which facilitates the subsequent process to react quickly with the phosphating solution. At the same time, the phosphating film is made denser and finer, which is more conducive to the powder in the subsequent drawing process.

[0013] Step d: Phosphating. The phosphating solution of the wire is generally prepared with phosphoric acid and zinc nitrate. In addition, in order to shorten the phosphating time and speed up the phosphating reaction, the working temperature of the phosphating solution is controlled at an appropriate temperature;

[0014] Step e: Secondary water washing, the residual phosphating liquid on the surface of the wire is washed clean by high-pressure water;

[0015] Step f: Saponification: after the entire pretreatment line is completed, a saponification layer is coated on the surface of the wire;

[0016] Step 2: Drawing the semi-finished product. This step is divided into three drawing steps. The pickled and phosphating wire is drawn to the semi-finished product specifications through a straight-through wire drawing machine, and heat treatment is performed after each drawing.

[0017] Step 3: Recrystallization annealing, through low-temperature recrystallization annealing to eliminate the work hardening produced in the drawing process, and continue deep processing in the later stage, through the low-temperature recrystallization process to eliminate the work hardening produced in the previous drawing process, at the same time, through the annealing process;

[0018] By adopting the above technical solution, ventilation is carried out throughout the annealing process, which can reduce the risk of decarburization of the steel wire;

[0019] Step 4: Pickling and phosphating, semi-finished product surface treatment, remove the slight decarburization layer on the surface of the semi-finished product, and prepare the surface coating for the subsequent drawing;

[0020] Step 5: Water tank drawing, the water tank drawing process is used in the final semi-finished product;

[0021] By adopting the above technical solution, the difference between semi-finished product drawing, water tank wire drawing and straight-through wire drawing lies in the different drawing media. The surface of the steel wire after water tank wire drawing is clean, while there is more residual wire drawing powder on the surface of the steel wire after straight-through drawing. However, the drawing efficiency of the straight-through drawing is much higher than that of the water tank drawing. The water tank drawing process can make the surface of the steel wire clean.

[0022] Step 6: Finishing: After the semi-finished product is annealed, the finishing process is used to achieve the dimensional tolerance of the finished product and at the same time, improve the cleanliness of the steel wire surface;

[0023] Step 7: Straightening: straightening the needle latch wire through the straightening process;

[0024] The straightening process in step 7 includes the following steps:

[0025] Step 1: Paying off the wire, use the horizontal pay-off machine to smoothly pay off the semi-finished steel wire of the B60 I-shaped wheel. The pay-off machine number and the take-up machine number need to correspond one to one to avoid mixing;

[0026] Step 2: Surface cleaning: Use an ultrasonic transmitter to clean the surface of the semi-finished product with sodium hydroxide solution to remove the saponified liquid on the surface of the incoming steel wire. The concentration of the sodium hydroxide solution is controlled by pH within the range of 11-13 g / L.

[0027] Step 3: Drying: remove the residual moisture on the surface of the steel wire to prevent the steel wire from entering the heating furnace with moisture on the surface, which may cause abnormal structure and decarburization of the steel wire. The drying temperature is generally controlled in the range of 90-130°C.

[0028] Step 4: Heating furnace, by heating the surface of the steel wire to remove the work hardening caused by the previous processing, so as to ensure that the bow height of the steel wire meets the requirements;

[0029] Step 5: Reeling in the wire, reeling in the wire at a set speed through the traction drum;

[0030] Step 6: Take a 1m long needle tongue finished steel wire, press one side of the steel wire, and the steel wire is qualified if the outward inclination angle is less than 6°.

[0031] Preferably, the thickness of the phosphate film on the surface of the steel wire in step 1 is 6 to 8 g / m 2 .

[0032] By adopting the above technical solution, the oxide on the surface is removed cleanly to avoid the decarburization defect of the edge steel wire in the subsequent annealing process. The phosphating film is coated on the surface of the steel wire to facilitate the drawing of the subsequent semi-finished product.

[0033] Preferably, the hydrochloric acid concentration in step a is 100-150 g / L, the pickling temperature is 35-45° C., and a closed acid mist treatment device is used during pickling.

[0034] By adopting the above technical solution, a suitable temperature of 35 to 45°C is adopted. The higher the temperature, the more the hydrochloric acid evaporates, which has a great impact on the environment and increases the consumption of hydrochloric acid. In view of the volatility of hydrochloric acid, the pickling is carried out through acid mist treatment equipment to avoid acid mist overflow.

[0035] Preferably, the pH value in step c is controlled at 7-9.

[0036] Preferably, the total acidity of phosphoric acid and zinc nitrate in step d is controlled to be 100-120 g / L, the acid ratio is controlled to be 7-10, and the working temperature of the phosphating solution is between 70 and 80°C.

[0037] By adopting the above technical solution, the phosphating time can be shortened and the phosphating reaction speed can be accelerated.

[0038] Preferably, the saponification process temperature in step f is 60-70° C., and the pH is 8-10.

[0039] By adopting the above technical solution, it is easier to carry wire drawing powder during the subsequent drawing process.

[0040] Preferably, in the drawing process in step 2, attention should be paid to the size and surface quality of the steel wire, and the mold is matched as follows: Φ5.50-Φ4.90-Φ4.35-Φ3.85-Φ3.45-Φ3.05-Φ2.80-Φ2.50, Φ2.50-Φ2.25-Φ2.00-Φ1.80-Φ1.60, Φ1.60-Φ1.45-Φ1.30-Φ1.18-Φ1.08-Φ0.98-Φ0.90.

[0041] By adopting the above technical solution, the work hardening caused by drawing can be eliminated.

[0042] Preferably, the intermediate heat treatment of the needle tongue steel wire in step 3 during the entire process adopts recrystallization annealing, and the specific annealing process is as follows:

[0043] Annealing stage Spheroidization temperature Insulation time Annealing stage Spheroidization temperature Insulation time Annealing 1 stage 180℃ 10min Annealing 4 stages 500℃ 20min Annealing 2 stages 300℃ 20min Annealing 5 stages 550℃ 30min Annealing 3 stages 350℃ 30min Annealing 6 stages 650℃ 420min .

[0044] Preferably, the temperature involved in step 4 is as follows:

[0045] Serial number Material Specification Heating temperature℃ Rewinding speed tensile strength 1 GRST100 0.31mm 650℃ 20m / min 575Mpa 2 GRST100 0.29mm 650℃ 45m / min 807Mpa .

[0046] The benefits of the present invention are as follows: 1. The present invention utilizes online annealing to straighten the needle latch steel wire, and can produce needle latch steel wire with good straightness, effectively improving the product quality of the needle latch steel wire, effectively reducing the frequency of shunting during use, and increasing the service life of the needle latch.

[0047] 2. When the steel wire of the present invention is rolled, since the steel wire has good straightness, the force on the steel wire is uniform during rolling, that is, the size of the rolled steel wire is also relatively uniform in this case, thereby extending the service life.

[0048] 3. The present invention uses a straightened needle tongue to facilitate the entanglement phenomenon in the later combing process, thereby improving the adaptability of the combing. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a schematic diagram of the needle tongue structure of the present invention;

[0050] Figure 2 It is a schematic diagram of acceptance of the present invention.

[0051] Among them: 1. Needle tongue. DETAILED DESCRIPTION

[0052] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0053] Example 1

[0054] A needle latch steel wire production process comprises the following steps:

[0055] Step 1: The raw materials are pickled and phosphated. The phosphating film is coated on the surface of the steel wire by hydrochloric acid pickling. The thickness of the phosphating film on the surface of the steel wire is 6g / m 2 , remove the surface oxides to avoid the decarburization defect of the edge steel wire in the subsequent annealing process, and coat the phosphating film on the surface of the steel wire to facilitate the drawing of the subsequent semi-finished products;

[0056] Step a: Acidification is achieved by using low-concentration hydrochloric acid, the concentration of which is 100g / L, and the pickling temperature is 35°C. When pickling, a closed acid mist treatment device is used with an appropriate temperature. The higher the temperature, the more the hydrochloric acid volatilizes, which has a great impact on the environment and increases the consumption of hydrochloric acid. In view of the volatility of hydrochloric acid, pickling is carried out through an acid mist treatment device to avoid acid mist overflow;

[0057] Step b: primary water washing, the residual acid on the surface of the wire is washed clean by high-pressure water;

[0058] By adopting the above technical solution, since some hydrochloric acid will remain on the surface of the wire after pickling, in order to avoid the influence of the residual hydrochloric acid on the subsequent process, an additional water washing step can remove the residual hydrochloric acid on the surface of the wire;

[0059] Step c: Surface adjustment, by adding a surface adjuster into a medium-temperature water pool, the surface adjuster solution is controlled by the pH index, and the pH value is controlled at 7;

[0060] It plays the role of surface pretreatment before phosphating, which facilitates the subsequent process to react quickly with the phosphating solution. At the same time, it makes the phosphating film more dense and delicate, which is more conducive to the powder in the subsequent drawing process.

[0061] Step d: Phosphating. The phosphating solution of the wire is generally prepared with phosphoric acid and zinc nitrate. In addition, in order to shorten the phosphating time and speed up the phosphating reaction, the working temperature of the phosphating solution is controlled at an appropriate temperature. The total acidity of phosphoric acid and zinc nitrate is controlled to 100g / L, the acid ratio is controlled to 7, and the working temperature of the phosphating solution is between 70°C, which can shorten the phosphating time and speed up the phosphating reaction.

[0062] Step e: Secondary water washing, the residual phosphating liquid on the surface of the wire is washed clean by high-pressure water;

[0063] Step f: Saponification: after the entire pretreatment line is completed, a saponification layer is coated on the surface of the wire. The saponification process temperature is 60°C and the pH is 8.

[0064] Step 2: Drawing the semi-finished product. This step is divided into three drawing steps. The pickled and phosphated wire is drawn to the semi-finished product specifications through a straight-through wire drawing machine. Heat treatment is performed after each drawing, which is convenient for carrying wire drawing powder in the subsequent drawing process;

[0065] Step 3: Recrystallization annealing, through low-temperature recrystallization annealing to eliminate the work hardening produced in the drawing process, and continue deep processing in the later stage, through the low-temperature recrystallization process to eliminate the work hardening produced in the previous drawing process, at the same time, through the annealing process;

[0066] Ventilation during the entire annealing process can reduce the risk of decarburization of the steel wire;

[0067] Step 4: Pickling and phosphating, semi-finished product surface treatment, remove the slight decarburization layer on the surface of the semi-finished product, and prepare the surface coating for the subsequent drawing;

[0068] Step 5: Water tank drawing, the water tank drawing process is used in the final semi-finished product;

[0069] By adopting the above technical solution, the difference between semi-finished product drawing, water tank wire drawing and straight-through wire drawing lies in the different drawing media. The surface of the steel wire after water tank wire drawing is clean, while there is more residual wire drawing powder on the surface of the steel wire after straight-through drawing. However, the drawing efficiency of the straight-through drawing is much higher than that of the water tank drawing. The water tank drawing process can make the surface of the steel wire clean.

[0070] Step 6: Finishing: After the semi-finished product is annealed, the finishing process is used to achieve the dimensional tolerance of the finished product and at the same time, improve the cleanliness of the steel wire surface;

[0071] Step 7: Straightening: straightening the needle latch wire through the straightening process;

[0072] The straightening process in step 7 includes the following steps:

[0073] Step 1: Paying off the wire, use the horizontal pay-off machine to smoothly pay off the semi-finished steel wire of the B60 I-shaped wheel. The pay-off machine number and the take-up machine number need to correspond one to one to avoid mixing;

[0074] Step 2: Surface cleaning: Use an ultrasonic transmitter to clean the surface of the semi-finished product with sodium hydroxide solution to remove the saponified liquid on the surface of the incoming steel wire. The concentration of the sodium hydroxide solution is controlled by pH within the range of 11g / L.

[0075] Step 3: Drying: remove the residual moisture on the surface of the steel wire to prevent the steel wire from entering the heating furnace with moisture on the surface, which may cause abnormal structure and decarburization of the steel wire. The drying temperature is generally controlled in the range of 90-130°C.

[0076] Step 4: Heating furnace, by heating the surface of the steel wire to remove the work hardening caused by the previous processing, so as to ensure that the bow height of the steel wire meets the requirements;

[0077] Step 5: Reeling in the wire, reeling in the wire at a set speed through the traction reel. The reeling can be done by loose frame reeling or I-shaped reel reeling, meeting customer needs while increasing the flexibility of production plans;

[0078] Step 6: If Figure 2 As shown, take a 1m long needle tongue finished steel wire, press one side of the steel wire, and the steel wire is qualified if the outward inclination angle is less than 6°.

[0079] During the drawing process in step 2, attention should be paid to the size and surface quality of the steel wire. The die is matched as follows: Φ5.50-Φ4.90-Φ4.35-Φ3.85-Φ3.45-Φ3.05-Φ2.80-Φ2.50, which can eliminate the work hardening caused by drawing.

[0080] The intermediate heat treatment of the needle tongue steel wire in step 3 adopts recrystallization annealing throughout the process. The specific annealing process is as follows:

[0081] Annealing stage Spheroidization temperature Insulation time Annealing stage Spheroidization temperature Insulation time Annealing 1 stage 180℃ 10min Annealing 4 stages 500℃ 20min Annealing 2 stages 300℃ 20min Annealing 5 stages 550℃ 30min Annealing 3 stages 350℃ 30min Annealing 6 stages 650℃ 420min .

[0082] The temperatures involved in step 4 are as follows:

[0083] Serial number Material Specification Heating temperature℃ Rewinding speed tensile strength 1 GRST100 0.31mm 650℃ 20m / min 575Mpa 2 GRST100 0.29mm 650℃ 45m / min 807Mpa .

[0084] Example 2

[0085] A needle latch steel wire production process comprises the following steps:

[0086] Step 1: The raw materials are pickled and phosphated. The phosphating film is coated on the surface of the steel wire through hydrochloric acid pickling. The thickness of the phosphating film on the surface of the steel wire is 7g / m2 , remove the surface oxides to avoid the decarburization defect of the edge steel wire in the subsequent annealing process, and coat the phosphating film on the surface of the steel wire to facilitate the drawing of the subsequent semi-finished products;

[0087] Step a: Acidification is achieved by using low-concentration hydrochloric acid. The concentration of hydrochloric acid is 120g / L and the pickling temperature is 40°C. When pickling, a closed acid mist treatment device is used. The temperature is appropriate. The higher the temperature, the more hydrochloric acid evaporates, which has a great impact on the environment and increases the consumption of hydrochloric acid. In view of the volatility of hydrochloric acid, pickling is carried out through acid mist treatment equipment to avoid acid mist overflow.

[0088] Step b: primary water washing, the residual acid on the surface of the wire is washed clean by high-pressure water;

[0089] Since some hydrochloric acid will remain on the surface of the wire after pickling, in order to avoid the influence of the residual hydrochloric acid on the subsequent process, an additional water wash can remove the residual hydrochloric acid on the surface of the wire;

[0090] Step c: Surface adjustment, by adding a surface adjuster into a medium-temperature water pool, the surface adjuster solution is controlled by the pH index, and the pH value is controlled at 8;

[0091] It plays the role of surface pretreatment before phosphating, which facilitates the subsequent process to react quickly with the phosphating solution. At the same time, it makes the phosphating film more dense and delicate, which is more conducive to the powder in the subsequent drawing process.

[0092] Step d: Phosphating. The phosphating solution of the wire is generally prepared with phosphoric acid and zinc nitrate. In addition, in order to shorten the phosphating time and accelerate the phosphating reaction speed, the working temperature of the phosphating solution is controlled at an appropriate temperature, the total acidity of phosphoric acid and zinc nitrate is controlled to be 100-120 g / L, the acid ratio is controlled to be 7-10, and the working temperature of the phosphating solution is between 70 and 80°C, which can shorten the phosphating time and accelerate the phosphating reaction speed;

[0093] Step e: Secondary water washing, the residual phosphating liquid on the surface of the wire is washed clean by high-pressure water;

[0094] Step f: Saponification: after the entire pretreatment line is completed, a saponification layer is coated on the surface of the wire. The saponification process temperature is 60-70°C and the pH is 8-10.

[0095] Step 2: Drawing the semi-finished product. This step is divided into three drawing steps. The pickled and phosphated wire is drawn to the semi-finished product specifications through a straight-through wire drawing machine. Heat treatment is performed after each drawing, which is convenient for carrying wire drawing powder in the subsequent drawing process;

[0096] Step 3: Recrystallization annealing, through low-temperature recrystallization annealing to eliminate the work hardening produced in the drawing process, and continue deep processing in the later stage, through the low-temperature recrystallization process to eliminate the work hardening produced in the previous drawing process, at the same time, through the annealing process;

[0097] Ventilation during the entire annealing process can reduce the risk of decarburization of the steel wire;

[0098] Step 4: Pickling and phosphating, semi-finished product surface treatment, remove the slight decarburization layer on the surface of the semi-finished product, and prepare the surface coating for the subsequent drawing;

[0099] Step 5: Water tank drawing, the water tank drawing process is used in the final semi-finished product;

[0100] Semi-finished product drawing, the difference between water tank wire drawing and straight-in wire drawing lies in the different drawing media. The surface of the steel wire after water tank wire drawing is clean, while there is more residual wire drawing powder on the surface of the steel wire after straight-in wire drawing. However, the drawing efficiency of the straight-in wire drawing is much higher than that of the water tank drawing. The water tank drawing process can make the surface of the steel wire clean.

[0101] Step 6: Finishing: After the semi-finished product is annealed, the finishing process is used to achieve the dimensional tolerance of the finished product and at the same time, improve the cleanliness of the steel wire surface;

[0102] Step 7: Straightening: straightening the needle latch wire through the straightening process;

[0103] The straightening process in step 7 includes the following steps:

[0104] Step 1: Paying off the wire, use the horizontal pay-off machine to smoothly pay off the semi-finished steel wire of the B60 I-shaped wheel. The pay-off machine number and the take-up machine number need to correspond one to one to avoid mixing;

[0105] Step 2: Surface cleaning: Use an ultrasonic transmitter to clean the surface of the semi-finished product with sodium hydroxide solution to remove the saponified liquid on the surface of the incoming steel wire. The concentration of the sodium hydroxide solution is controlled by pH within the range of 12g / L.

[0106] Step 3: Drying: clean the residual moisture on the surface of the steel wire to prevent the steel wire from entering the heating furnace with moisture on the surface, which may cause abnormal structure and decarburization of the steel wire. The drying temperature is generally controlled within the temperature range of 100°C.

[0107] Step 4: Heating furnace, by heating the surface of the steel wire to remove the work hardening caused by the previous processing, so as to ensure that the bow height of the steel wire meets the requirements;

[0108] Step 5: Reeling in the wire, reeling in the wire at a set speed through the traction reel. The reeling can be done by loose frame reeling or I-shaped reel reeling, meeting customer needs while increasing the flexibility of production plans;

[0109] Step 6: Take a 1m long needle tongue finished steel wire, press one side of the steel wire, and the steel wire is qualified if the outward inclination angle is less than 6°.

[0110] During the drawing process in step 2, attention should be paid to the size and surface quality of the steel wire. The die is matched as follows: Φ2.50-Φ2.25-Φ2.00-Φ1.80-Φ1.60, which can eliminate the work hardening caused by drawing.

[0111] The intermediate heat treatment of the needle tongue steel wire in step 3 adopts recrystallization annealing throughout the process. The specific annealing process is as follows:

[0112] Annealing stage Spheroidization temperature Insulation time Annealing stage Spheroidization temperature Insulation time Annealing 1 stage 180℃ 10min Annealing 4 stages 500℃ 20min Annealing 2 stages 300℃ 20min Annealing 5 stages 550℃ 30min Annealing 3 stages 350℃ 30min Annealing 6 stages 650℃ 420min .

[0113] The temperatures involved in step 4 are as follows:

[0114] Serial number Material Specification Heating temperature℃ Rewinding speed tensile strength 1 GRST100 0.31mm 650℃ 20m / min 575Mpa 2 GRST100 0.29mm 650℃ 45m / min 807Mpa .

[0115] Example 3

[0116] A needle latch steel wire production process comprises the following steps:

[0117] Step 1: The raw materials are pickled and phosphated. The phosphating film is coated on the surface of the steel wire through hydrochloric acid pickling. The thickness of the phosphating film on the surface of the steel wire is 8g / m 2 , remove the surface oxides to avoid the decarburization defect of the edge steel wire in the subsequent annealing process, and coat the phosphating film on the surface of the steel wire to facilitate the drawing of the subsequent semi-finished products;

[0118] Step a: Acidification is achieved by using low-concentration hydrochloric acid, the concentration of which is 150 g / L, and the pickling temperature is 45°C. When pickling, a closed acid mist treatment device is used, and the temperature is appropriate. The higher the temperature, the more the hydrochloric acid volatilizes, which has a great impact on the environment and increases the consumption of hydrochloric acid. In view of the volatility of hydrochloric acid, pickling is carried out through an acid mist treatment device to avoid acid mist overflow;

[0119] Step b: primary water washing, the residual acid on the surface of the wire is washed clean by high-pressure water;

[0120] By adopting the above technical solution, since some hydrochloric acid will remain on the surface of the wire after pickling, in order to avoid the influence of the residual hydrochloric acid on the subsequent process, an additional water washing step can remove the residual hydrochloric acid on the surface of the wire;

[0121] Step c: Surface adjustment, by adding a surface adjuster in a medium-temperature water pool, the surface adjuster solution is controlled by the pH index, and the pH value is controlled at 9, which plays the role of surface pretreatment before phosphating, facilitating the subsequent process to react quickly with the phosphating solution, and at the same time, making the phosphating film more dense and delicate, which is more conducive to the powder in the subsequent drawing process;

[0122] Step d: Phosphating. The phosphating solution of the wire is generally prepared with phosphoric acid and zinc nitrate. In addition, in order to shorten the phosphating time and speed up the phosphating reaction, the working temperature of the phosphating solution is controlled at an appropriate temperature. The total acidity of phosphoric acid and zinc nitrate is controlled to 120g / L, the acid ratio is controlled to 10, and the working temperature of the phosphating solution is between 80°C, which can shorten the phosphating time and speed up the phosphating reaction.

[0123] Step e: Secondary water washing, the residual phosphating liquid on the surface of the wire is washed clean by high-pressure water;

[0124] Step f: Saponification: after the entire pretreatment line is completed, a saponification layer is coated on the surface of the wire. The saponification process temperature is 70°C and the pH is 10.

[0125] Step 2: Drawing the semi-finished product. This step is divided into three drawing steps. The pickled and phosphated wire is drawn to the semi-finished product specifications through a straight-through wire drawing machine. Heat treatment is performed after each drawing, which is convenient for carrying wire drawing powder in the subsequent drawing process;

[0126] Step 3: Recrystallization annealing, through low-temperature recrystallization annealing to eliminate the work hardening produced in the drawing process, and continue deep processing in the later stage, through the low-temperature recrystallization process to eliminate the work hardening produced in the previous drawing process, at the same time, through the whole annealing process, the whole annealing process can reduce the risk of decarburization of the steel wire;

[0127] Step 4: Pickling and phosphating, semi-finished product surface treatment, remove the slight decarburization layer on the surface of the semi-finished product, and prepare the surface coating for the subsequent drawing;

[0128] Step 5: Water tank wire drawing. The water tank drawing process is used for the final semi-finished product. The difference between water tank wire drawing and straight-line wire drawing is that the drawing medium is different. The surface of the steel wire after water tank wire drawing is clean, and there is more residual wire drawing powder on the surface of the steel wire after straight-line drawing. However, the straight-line drawing efficiency is much higher than that of water tank drawing. The water tank drawing process can make the surface of the steel wire clean;

[0129] Step 6: Finishing: After the semi-finished product is annealed, the finishing process is used to achieve the dimensional tolerance of the finished product and at the same time, improve the cleanliness of the steel wire surface;

[0130] Step 7: Straightening: straightening the needle latch wire through the straightening process;

[0131] The straightening process in step 7 includes the following steps:

[0132] Step 1: Paying off the wire, use the horizontal pay-off machine to smoothly pay off the semi-finished steel wire of the B60 I-shaped wheel. The pay-off machine number and the take-up machine number need to correspond one to one to avoid mixing;

[0133] Step 2: Surface cleaning: Use an ultrasonic transmitter to clean the surface of the semi-finished product with sodium hydroxide solution to remove the saponified liquid on the surface of the incoming steel wire. The concentration of the sodium hydroxide solution is controlled by pH within the range of 13g / L.

[0134] Step 3: Drying: clean the residual moisture on the surface of the steel wire to prevent the steel wire from entering the heating furnace with moisture on the surface, which may cause abnormal structure and decarburization of the steel wire. The drying temperature is generally controlled within the temperature range of 130°C.

[0135] Step 4: Heating furnace, by heating the surface of the steel wire to remove the work hardening caused by the previous processing, so as to ensure that the bow height of the steel wire meets the requirements;

[0136] Step 5: Reeling in the wire, reeling in the wire at a set speed through the traction reel. The reeling can be done by loose frame reeling or I-shaped reel reeling, meeting customer needs while increasing the flexibility of production plans;

[0137] Step 6: Take a 1m long needle tongue finished steel wire, press one side of the steel wire, and the steel wire is qualified if the outward inclination angle is less than 6°.

[0138] During the drawing process in step 2, attention should be paid to the size and surface quality of the steel wire. The die is matched as follows: Φ1.60-Φ1.45-Φ1.30-Φ1.18-Φ1.08-Φ0.98-Φ0.90, which can eliminate the work hardening caused by drawing.

[0139] The intermediate heat treatment of the needle tongue steel wire in step 3 adopts recrystallization annealing throughout the process. The specific annealing process is as follows:

[0140] Annealing stage Spheroidization temperature Insulation time Annealing stage Spheroidization temperature Insulation time Annealing 1 stage 180℃ 10min Annealing 4 stages 500℃ 20min Annealing 2 stages 300℃ 20min Annealing 5 stages 550℃ 30min Annealing 3 stages 350℃ 30min Annealing 6 stages 650℃ 420min .

[0141] The temperatures involved in step 4 are as follows:

[0142] Serial number Material Specification Heating temperature ℃ Rewinding speed tensile strength 1 GRST100 0.31mm 650℃ 20m / min 575Mpa 2 GRST100 0.29mm 650℃ 45m / min 807Mpa .

[0143] Example 4

[0144] A needle latch steel wire production process comprises the following steps:

[0145] Step 1: The raw materials are pickled and phosphated. The phosphating film is coated on the surface of the steel wire through hydrochloric acid pickling. The thickness of the phosphating film on the surface of the steel wire is 8g / m 2 , remove the surface oxides to avoid the decarburization defect of the edge steel wire in the subsequent annealing process, and coat the phosphating film on the surface of the steel wire to facilitate the drawing of the subsequent semi-finished products;

[0146] Step a: Acidification is achieved by using low-concentration hydrochloric acid, the concentration of which is 140 g / L, and the pickling temperature is 35-45°C. When pickling, a closed acid mist treatment device is used, and the temperature is appropriate. The higher the temperature, the more the hydrochloric acid volatilizes, which has a great impact on the environment and increases the consumption of hydrochloric acid. In view of the volatility of hydrochloric acid, pickling is carried out through an acid mist treatment device to avoid acid mist overflow;

[0147] Step b: primary water washing, the residual acid on the surface of the wire is washed clean by high-pressure water;

[0148] By adopting the above technical solution, since some hydrochloric acid will remain on the surface of the wire after pickling, in order to avoid the influence of the residual hydrochloric acid on the subsequent process, an additional water washing step can remove the residual hydrochloric acid on the surface of the wire;

[0149] Step c: Surface adjustment, by adding a surface adjuster in a medium-temperature water pool, the surface adjuster solution is controlled by the pH index, and the pH value is controlled at 8, which plays the role of surface pretreatment before phosphating, facilitating the subsequent process to react quickly with the phosphating solution, and at the same time, making the phosphating film more dense and delicate, which is more conducive to the powder in the subsequent drawing process;

[0150] Step d: Phosphating. The phosphating solution of the wire is generally prepared with phosphoric acid and zinc nitrate. In addition, in order to shorten the phosphating time and speed up the phosphating reaction, the working temperature of the phosphating solution is controlled at an appropriate temperature. The total acidity of phosphoric acid and zinc nitrate is controlled to 120g / L, the acid ratio is controlled to 10, and the working temperature of the phosphating solution is between 80°C, which can shorten the phosphating time and speed up the phosphating reaction.

[0151] Step e: Secondary water washing, the residual phosphating liquid on the surface of the wire is washed clean by high-pressure water;

[0152] Step f: Saponification: after the entire pretreatment line is completed, a saponification layer is coated on the surface of the wire. The saponification process temperature is 80°C and the pH is 10.

[0153] Step 2: Drawing the semi-finished product. This step is divided into three drawing steps. The pickled and phosphated wire is drawn to the semi-finished product specifications through a straight-through wire drawing machine. Heat treatment is performed after each drawing, which is convenient for carrying wire drawing powder in the subsequent drawing process;

[0154] Step 3: Recrystallization annealing, through low-temperature recrystallization annealing to eliminate the work hardening produced in the drawing process, and continue deep processing in the later stage, through the low-temperature recrystallization process to eliminate the work hardening produced in the previous drawing process, at the same time, through the annealing process;

[0155] By adopting the above technical solution, the risk of decarburization of the steel wire can be reduced by ventilation during the entire annealing process;

[0156] Step 4: Pickling and phosphating, semi-finished product surface treatment, remove the slight decarburization layer on the surface of the semi-finished product, and prepare the surface coating for the subsequent drawing;

[0157] Step 5: Water tank wire drawing. The water tank drawing process is used for the final semi-finished product. The difference between water tank wire drawing and straight-line wire drawing is that the drawing medium is different. The surface of the steel wire after water tank wire drawing is clean, and there is more residual wire drawing powder on the surface of the steel wire after straight-line drawing. However, the straight-line drawing efficiency is much higher than that of water tank drawing. The water tank drawing process can make the surface of the steel wire clean;

[0158] Step 6: Finishing: After the semi-finished product is annealed, the finishing process is used to achieve the dimensional tolerance of the finished product and at the same time, improve the cleanliness of the steel wire surface;

[0159] Step 7: Straightening: straightening the needle latch wire through the straightening process;

[0160] The straightening process in step 7 includes the following steps:

[0161] Step 1: Paying off the wire, use the horizontal pay-off machine to smoothly pay off the semi-finished steel wire of the B60 I-shaped wheel. The pay-off machine number and the take-up machine number need to correspond one to one to avoid mixing;

[0162] Step 2: Surface cleaning: Use an ultrasonic transmitter to clean the surface of the semi-finished product with sodium hydroxide solution to remove the saponified liquid on the surface of the incoming steel wire. The concentration of the sodium hydroxide solution is controlled by pH within the range of 13g / L.

[0163] Step 3: Drying: remove the residual moisture on the surface of the steel wire to prevent the steel wire from entering the heating furnace with moisture on the surface, which may cause abnormal structure and decarburization of the steel wire. The drying temperature is generally controlled in the range of 90-130°C.

[0164] Step 4: Heating furnace, by heating the surface of the steel wire to remove the work hardening caused by the previous processing, so as to ensure that the bow height of the steel wire meets the requirements;

[0165] Step 5: Reeling in the wire, reeling in the wire at a set speed through the traction reel. The reeling can be done by loose frame reeling or I-shaped reel reeling, meeting customer needs while increasing the flexibility of production plans;

[0166] Step 6: Take a 1m long needle tongue finished steel wire, press one side of the steel wire, and the steel wire is qualified if the outward inclination angle is less than 6°.

[0167] During the drawing process in step 2, attention should be paid to the size and surface quality of the steel wire. The die is matched as follows: Φ1.60-Φ1.45-Φ1.30-Φ1.18-Φ1.08-Φ0.98-Φ0.90, which can eliminate the work hardening caused by drawing.

[0168] The intermediate heat treatment of the needle tongue steel wire in step 3 adopts recrystallization annealing throughout the process. The specific annealing process is as follows:

[0169] Annealing stage Spheroidization temperature Insulation time Annealing stage Spheroidization temperature Insulation time Annealing 1 stage 180℃ 10min Annealing 4 stages 500℃ 20min Annealing 2 stages 300℃ 20min Annealing 5 stages 550℃ 30min Annealing 3 stages 350℃ 30min Annealing 6 stages 650℃ 420min .

[0170] The temperatures involved in step 4 are as follows:

[0171] Serial number Material Specification Heating temperature℃ Rewinding speed tensile strength 1 GRST100 0.31mm 650℃ 20m / min 575Mpa 2 GRST100 0.29mm 650℃ 45m / min 807Mpa .

[0172] By using online annealing to straighten the needle latch wire, needle latch wire with good straightness can be produced, which effectively improves the product quality of the needle latch wire, effectively reduces the frequency of adjustment during use, and increases the service life of the needle latch.

[0173] It should be understood by those skilled in the art that the embodiments of the present invention described above and shown in the accompanying drawings are only examples and do not limit the present invention, and the purpose of the present invention has been fully and effectively achieved. The functional and structural principles of the present invention have been demonstrated and explained in the embodiments, and the embodiments of the present invention may be deformed or modified in any way without departing from the principles.

Claims

1. A needle latch steel wire production process, characterized in that: The following steps are involved: Step 1: The raw materials are pickled and phosphated, and a phosphating film is applied on the surface of the steel wire by pickling with hydrochloric acid; Step a: Acidification, achieved by low concentration hydrochloric acid; Step b: primary water washing, the residual acid on the surface of the wire is washed clean by high-pressure water; Step c: Surface adjustment, by adding a surface adjuster into a medium-temperature water pool, and the surface adjuster solution is controlled by the pH index; Step d: Phosphating, the phosphating solution of the wire is prepared by phosphoric acid and zinc nitrate. In addition, in order to shorten the phosphating time and speed up the phosphating reaction speed, the working temperature of the phosphating solution is controlled at an appropriate temperature; Step e: Secondary water washing, the residual phosphating liquid on the surface of the wire is washed clean by high-pressure water; Step f: Saponification: after the entire pretreatment line is completed, a saponification layer is coated on the surface of the wire; Step 2: Drawing the semi-finished product. This step is divided into three drawing steps. The pickled and phosphating wire is drawn to the semi-finished product specifications through a straight-through wire drawing machine, and heat treatment is performed after each drawing. Step 3: Recrystallization annealing, through low-temperature recrystallization annealing to eliminate the work hardening produced in the drawing process, and continue deep processing in the later stage, through the low-temperature recrystallization process to eliminate the work hardening produced in the previous drawing process, and at the same time, the whole annealing process is ventilated; Step 4: Pickling and phosphating, semi-finished product surface treatment, remove the slight decarburization layer on the surface of the semi-finished product, and prepare the surface coating for the subsequent drawing; Step 5: Water tank drawing, the water tank drawing process is used in the final semi-finished product; Step 6: Finishing: After the semi-finished product is annealed, the finishing process is used to achieve the dimensional tolerance of the finished product and at the same time, improve the cleanliness of the steel wire surface; Step 7: Straightening: straightening the needle latch wire through the straightening process; The straightening process in step 7 includes the following steps: Step 71: Paying off the wire, using the horizontal pay-off machine to smoothly pay off the semi-finished steel wire that is taken up by the B60 I-shaped wheel. The pay-off machine number and the take-up machine number need to correspond one to one to avoid mixing of materials; Step 72: Surface cleaning: using an ultrasonic transmitter to clean the surface of the semi-finished product with a sodium hydroxide solution, so as to remove the saponified liquid on the surface of the incoming steel wire. The concentration of the sodium hydroxide solution is controlled by pH value within the range of 11-13 g / L. Step 73: Drying, removing the residual moisture on the surface of the steel wire to prevent the steel wire from entering the heating furnace with moisture on the surface, causing abnormal structure and decarburization of the steel wire. The drying temperature is generally controlled in the temperature range of 90-130°C; Step 74: A heating furnace is used to heat the surface of the steel wire to remove the work hardening caused by the previous processing, thereby ensuring that the bow height of the steel wire meets the requirements; Step 75: Reeling in the wire, reeling in the wire at a set speed by pulling the reel; Step 76: Take a 1m long needle tongue finished steel wire, press one side of the steel wire, and the steel wire is qualified if the outward inclination angle is less than 6°.

2. A needle latch steel wire production process according to claim 1, characterized in that: The thickness of the phosphate film on the surface of the steel wire in step 1 is 6-8 g / m 2 .

3. A needle latch steel wire production process according to claim 1, characterized in that: The hydrochloric acid concentration in step a is 100-150 g / L, the pickling temperature is 35-45° C., and a closed acid mist treatment device is used during pickling.

4. A needle latch steel wire production process according to claim 1, characterized in that: The pH value in step c is controlled at 7-9.

5. A needle latch steel wire production process according to claim 1, characterized in that: The total acidity of phosphoric acid and zinc nitrate in step d is controlled to be 100-120 g / L, the acid ratio is controlled to be 7-10, and the working temperature of the phosphating solution is between 70-80° C.

6. A needle latch steel wire production process according to claim 1, characterized in that: The saponification process temperature in step f is 60-70° C., and the pH is 8-10.

7. A needle latch steel wire production process according to claim 1, characterized in that: During the drawing process in step 2, attention should be paid to the size and surface quality of the steel wire, and the molds are as follows: Φ5.50-Φ4.90-Φ4.35-Φ3.85-Φ3.45-Φ3.05-Φ2.80-Φ2.50, Φ2.50-Φ2.25-Φ2.00-Φ1.80-Φ1.60, Φ1.60-Φ1.45-Φ1.30-Φ1.18-Φ1.08-Φ0.98-Φ0.90.

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