CN115502324A - Manufacturing method of non-quenched and tempered bolt - Google Patents
Manufacturing method of non-quenched and tempered bolt Download PDFInfo
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- CN115502324A CN115502324A CN202211118147.1A CN202211118147A CN115502324A CN 115502324 A CN115502324 A CN 115502324A CN 202211118147 A CN202211118147 A CN 202211118147A CN 115502324 A CN115502324 A CN 115502324A
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- 238000004519 manufacturing process Methods 0.000 title claims abstract description 33
- 238000001816 cooling Methods 0.000 claims abstract description 19
- 238000000034 method Methods 0.000 claims abstract description 14
- 238000007664 blowing Methods 0.000 claims abstract description 11
- 238000010622 cold drawing Methods 0.000 claims abstract description 11
- 238000010438 heat treatment Methods 0.000 claims abstract description 11
- 239000002994 raw material Substances 0.000 claims abstract description 10
- 238000004381 surface treatment Methods 0.000 claims abstract description 9
- 238000005096 rolling process Methods 0.000 claims abstract description 7
- FBPFZTCFMRRESA-JGWLITMVSA-N D-glucitol Chemical compound OC[C@H](O)[C@@H](O)[C@H](O)[C@H](O)CO FBPFZTCFMRRESA-JGWLITMVSA-N 0.000 claims abstract description 5
- 238000005422 blasting Methods 0.000 claims description 7
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 claims description 7
- 238000002791 soaking Methods 0.000 claims description 7
- 239000000126 substance Substances 0.000 claims description 5
- 238000005482 strain hardening Methods 0.000 description 8
- 238000005496 tempering Methods 0.000 description 7
- 239000000463 material Substances 0.000 description 6
- 230000000052 comparative effect Effects 0.000 description 5
- 238000010791 quenching Methods 0.000 description 4
- 238000007127 saponification reaction Methods 0.000 description 4
- 238000005265 energy consumption Methods 0.000 description 3
- 238000005554 pickling Methods 0.000 description 3
- 230000000171 quenching effect Effects 0.000 description 3
- 229910000831 Steel Inorganic materials 0.000 description 2
- 230000032683 aging Effects 0.000 description 2
- 238000000137 annealing Methods 0.000 description 2
- 238000005336 cracking Methods 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- 229910000712 Boron steel Inorganic materials 0.000 description 1
- 229910000975 Carbon steel Inorganic materials 0.000 description 1
- 229910000677 High-carbon steel Inorganic materials 0.000 description 1
- 229910000954 Medium-carbon steel Inorganic materials 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 239000010962 carbon steel Substances 0.000 description 1
- 239000002894 chemical waste Substances 0.000 description 1
- 238000000641 cold extrusion Methods 0.000 description 1
- 238000010273 cold forging Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005098 hot rolling Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000002203 pretreatment Methods 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000002918 waste heat Substances 0.000 description 1
Images
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21K—MAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS
- B21K1/00—Making machine elements
- B21K1/44—Making machine elements bolts, studs, or the like
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
- B21J5/00—Methods for forging, hammering, or pressing; Special equipment or accessories therefor
- B21J5/002—Hybrid process, e.g. forging following casting
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/42—Ferrous alloys, e.g. steel alloys containing chromium with nickel with copper
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/58—Ferrous alloys, e.g. steel alloys containing chromium with nickel with more than 1.5% by weight of manganese
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Heat Treatment Of Steel (AREA)
- Heat Treatment Of Strip Materials And Filament Materials (AREA)
- Forging (AREA)
Abstract
The invention belongs to the technical field of fastener manufacturing, and particularly relates to a manufacturing method of a non-quenched and tempered bolt. The invention takes hot rolled wire rods as raw materials, and obtains the non-quenched and tempered bolt with the performance grade of 8.8-10.9 through cold drawing, hot upsetting and air blowing cooling. Firstly, hot-rolled wire rods are subjected to pretreatment and cold drawing processing to form fine wires; step two, heating the fine wire obtained in the step one to be not less than 800 ℃, and hot upsetting the heated fine wire into a bolt blank; step three, cooling the bolt blank obtained in the step two by blowing; and step four, processing the bolt blank obtained in the step three into a bolt finished product through working procedures of thread rolling, surface treatment and the like. According to the invention, by optimizing the manufacturing process of the 8.8-10.9-grade high-strength bolt, the non-quenched and tempered bolt with the sorbite metallographic structure is obtained, the plasticity of the bolt is effectively improved, and the fracture failure of the bolt is reduced.
Description
Technical Field
The invention belongs to the technical field of fastener manufacturing, and particularly relates to a manufacturing method of a non-quenched and tempered bolt.
Background
At present, domestic 8.8-10.9-level bolts are produced mainly by two types of production processes: the first type of production process is more traditional, and usually medium carbon steel hot-rolled wire rods are used as raw materials, and comprise boron steel, high-quality carbon steel and alloy steel, and quenching and tempering heat treatment is carried out after the bolts are processed to obtain tempered and tempered bolts with metallographic structures; the second type of production process is emerging, and usually, a non-quenched and tempered cold forging steel hot rolled wire rod is used as a raw material, and a metallographic structure obtained through material performance and work hardening is a work hardening structure non-quenched and tempered bolt. A representative process for the first type of production process is: the method comprises the following steps of wire rod-pickling-phosphating-saponification-drawing-spheroidizing annealing-pickling-phosphating-saponification-drawing-cold heading forming-thread rolling-quenching and tempering heat treatment-surface treatment, wherein the wire rod pretreatment adopts pickling, phosphating and saponification, the wire rod preparation needs two times of wire rod pretreatment and drawing, and one-time spheroidizing annealing is carried out, so that the tempered bolt with the metallographic structure is obtained, and the mechanical property of the bolt is ensured through the quenching and tempering heat treatment. The representative process flow of the second production process is as follows: the method comprises the steps of wire rod pickling, phosphorization, saponification, drawing, cold heading forming, thread rolling, artificial aging and surface treatment, wherein the wire rod is subjected to pickling, phosphorization and saponification, fine wire preparation is only subjected to one-time wire rod pretreatment and drawing, spheroidizing annealing and quenching and tempering heat treatment are not needed, the obtained bolt with a metallographic structure of a work hardening structure and a non-quenched and tempered structure is obtained, and the mechanical property of the bolt is ensured through material performance and work hardening (the material is subjected to cold drawing, cold heading, cold extrusion and the like at normal temperature). The work hardening is to improve the strength and the hardness of the material, the artificial aging is also to further improve the strength and the hardness, and the plasticity of the material is inevitably reduced depending on the work hardening; if the work hardening is cancelled, the traditional thinking can only go through the tempering heat treatment route.
It can be seen that the mechanical properties of the non-quenched and tempered bolt can meet the standard requirements, but the mechanical properties of the non-quenched and tempered bolt can be guaranteed by the production process of work hardening, so that the plasticity of the bolt is greatly reduced, the problem of bolt fracture failure is caused, and the actual internal control requirements of fastener manufacturing enterprises and fastener using enterprises cannot be met.
The invention develops a non-tempering bolt manufacturing method with low energy consumption, low cost, less pollution and easy operation by optimizing the manufacturing process of 8.8-10.9 grade high-strength bolts, effectively improves the plasticity of the bolts, reduces the fracture failure of the bolts, meets the actual internal control requirements of fastener manufacturing enterprises and using enterprises, realizes the replacement of the traditional tempering bolts, further realizes the industrial application, and is the problem to be solved at present.
Disclosure of Invention
In order to solve the problems, the invention obtains the non-quenched and tempered bolt with sorbite as metallographic structure by optimizing the manufacturing process of the 8.8-10.9-grade high-strength bolt, effectively improves the plasticity of the bolt and reduces the fracture failure of the bolt. The manufacturing method of the non-quenched and tempered bolt has the advantages of low energy consumption, low cost, less pollution, easiness in operation and the like.
A method for manufacturing a non-quenched and tempered bolt uses a hot rolled wire rod as a raw material, and obtains the non-quenched and tempered bolt with a performance grade of 8.8-10.9 through cold drawing, hot heading and air blowing cooling.
The stabilizing treatment process of the present invention will be described in detail below.
The non-quenched and tempered bolt of the invention comprises the following specific manufacturing steps:
firstly, hot-rolled wire rods are subjected to pretreatment and cold drawing processing to form fine lines; the hot-rolled wire rod comprises the following chemical components: the weight percentage is C:0.37 to 0.55%, si: less than or equal to 0.35 percent, mn:1.35 to 1.65%, al: 0.010-0.050%, P and S less than or equal to 0.025%, cr, ni and Cu less than or equal to 0.10%; the pretreatment method of the wire rod comprises shot blasting and lime water soaking;
the specification of the hot-rolled wire rod is phi 5.0-42.5 mm, and the specification of the cold-drawn wire rod is phi 4.2-40.0 mm;
step two, heating the fine wire obtained in the step one to 800-900 ℃, and hot upsetting the heated fine wire into a bolt blank;
thirdly, cooling the bolt blank obtained in the second step by blowing (the temperature after hot heading forming is basically consistent with the temperature of a finish line), cooling to 450 +/-10 ℃ at the cooling rate of 16-18 ℃/s, and then placing in air to naturally cool to the normal temperature;
and step four, processing the bolt blank obtained in the step three into a bolt finished product through thread rolling and surface treatment conventional procedures.
The manufacturing process flow of the non-quenched and tempered bolt comprises the following steps: the method comprises the steps of wire rod coiling, shot blasting, lime water soaking, drawing, fine line heating, hot heading forming, air blowing cooling, thread rolling and surface treatment, and has the advantages of low energy consumption, low cost, less pollution, easiness in operation and the like compared with the existing bolt manufacturing process.
The wire rod pretreatment scheme adopts shot blasting and lime water soaking to replace acid washing, phosphating and saponification, so that the wire rod pretreatment operation is simplified, the chemical waste liquid pollution is avoided, and the pretreatment cost is reduced;
common medium-high carbon steel hot-rolled wire rods with lower cost are selected as raw materials, and the forming cracking rate of the bolt can be reduced; the blow cooling is directly carried out after the hot heading forming, the waste heat utilization is realized, the mechanical performance of the bolt is ensured by obtaining the sorbite structure, and the sorbite has higher strength and good plasticity, so that the plasticity of the bolt is effectively improved, and the fracture failure of the bolt is reduced.
Drawings
Fig. 1 is a metallographic structure diagram of a bolt prepared in example 1.
Detailed Description
The non-quenched and tempered bolt of the invention takes a hot rolled wire rod as a raw material, and is obtained by cold drawing, hot upsetting and air blowing cooling, and the non-quenched and tempered bolt with the performance grade of 8.8-10.9 is prepared by the following specific manufacturing process flows: wire rod-shot blasting-lime water soaking-drawing-fine line heating-hot heading forming-air blowing cooling-thread rolling-surface treatment.
The specification of the hot-rolled wire rod as the raw material is phi 5.0-42.5 mm, and the chemical components are as follows: the weight percentage of C:0.37 to 0.55%, si: less than or equal to 0.35 percent, mn:1.35 to 1.65%, al: 0.010-0.050%, P and S less than or equal to 0.025%, cr, ni and Cu less than or equal to 0.10%, and the balance of Fe and inevitable impurities.
Practical production of 10.9-grade M16 non-quenched and tempered flange bolts is described below as examples and comparative examples.
Example 1
The raw material hot-rolled wire rod comprises the following chemical components in percentage by weight: 0.49%, si:0.20%, mn:1.60%, al:0.021%, P:0.018%, S:0.017%, cr:0.05%, ni:0.05%, cu:0.03 percent.
Firstly, carrying out shot blasting and lime water soaking pretreatment on a phi 18.0mm hot rolled wire rod, and carrying out cold drawing on the pretreated wire rod into a phi 17.2mm fine line by a drawing machine;
step two, heating the fine line obtained in the step one to 880 ℃, and performing hot heading on the heated fine line to obtain an M16 flange bolt blank;
step three, cooling the M16 flange bolt blank obtained in the step two by blowing air to 443 ℃ at the cooling rate of 17.5 ℃/s, and then placing the blank in air to naturally cool the blank to normal temperature;
and step four, processing the bolt blank obtained in the step three into a finished M16 flange bolt product through working procedures of thread rolling, surface treatment and the like.
Example 2
The raw material hot-rolled wire rod comprises the following chemical components in percentage by weight: 0.53%, si:0.32%, mn:1.52%, al:0.040%, P:0.022%, S:0.015%, cr:0.07%, ni:0.01%, cu:0.02 percent.
Firstly, carrying out shot blasting and lime water soaking pretreatment on a phi 18.0mm hot-rolled wire rod, and carrying out cold drawing on the pretreated wire rod by a drawing machine to form a phi 17.2mm fine line;
step two, heating the fine line obtained in the step one to 850 ℃, and performing hot heading on the heated fine line to obtain an M16 flange bolt blank;
step three, cooling the M16 flange bolt blank obtained in the step two by blowing air, cooling to 455 ℃ at a cooling rate of 16.5 ℃/s, and then placing in air for natural cooling to normal temperature;
and step four, processing the bolt blank obtained in the step three into a finished product of the M16 flange bolt through working procedures of thread rolling, surface treatment and the like.
Comparative example 1
Example 1, step two was replaced with: and (4) cold heading the fine line obtained in the first step into an M16 flange bolt blank, eliminating the third step and keeping the other conditions the same as those in the embodiment 1.
Comparative example 2
Example 1, step three was replaced with: and (3) placing the M16 flange bolt blank obtained in the step two in the air, and naturally cooling to normal temperature under the same conditions as in the embodiment 1.
Comparative example 3
The phi 18.0mm hot rolled wire rod in the first step of example 1 was replaced by: hot rolling the wire rod with the diameter of 20.0 mm; namely, the phi 20.0mm hot rolled wire rod is subjected to shot blasting and lime water soaking pretreatment and is cold drawn into a phi 17.2mm fine line by a drawing machine. Example 1, step two was replaced with: and (3) cold heading the fine line obtained in the step one into an M16 flange bolt blank, and eliminating the step three under the same other conditions as in the example 1.
The phi 18.0mm hot-rolled wire rod is replaced by the phi 20.0mm, the surface reduction rate of drawing processing is increased, the strength of the steel wire after drawing is improved, but the plasticity of the material is sharply reduced, and the forming cracking rate is linearly increased.
The proportion of 10.9-grade M16 non-quenched and tempered type flange bolt pairs produced in the examples and the comparative examples of the invention is shown in Table 1:
TABLE 1
Claims (7)
1. A manufacturing method of a non-quenched and tempered bolt is characterized in that: taking a hot-rolled wire rod as a raw material, and carrying out cold drawing, hot upsetting and air blowing cooling to obtain a non-quenched and tempered bolt with a performance grade of 8.8-10.9;
the specific manufacturing steps are as follows:
firstly, hot-rolled wire rods are subjected to pretreatment and cold drawing processing to form fine wires;
step two, heating the fine wire obtained in the step one to be not less than 800 ℃, and hot upsetting the heated fine wire into a bolt blank;
step three, cooling the bolt blank obtained in the step two by blowing;
and step four, processing the bolt blank obtained in the step three into a bolt finished product through thread rolling and surface treatment processes.
2. The method for manufacturing a non-heat-treated bolt according to claim 1, wherein: the hot-rolled wire rod comprises the following chemical components: the weight percentage is C:0.37 to 0.55%, si: less than or equal to 0.35 percent, mn:1.35 to 1.65%, al: 0.010-0.050%, P, S less than or equal to 0.025%, cr, ni, cu less than or equal to 0.10%.
3. The method of manufacturing a non heat-treated bolt according to claim 1, wherein: the first step is that the wire rod is pretreated by shot blasting and lime water soaking.
4. The method of manufacturing a non heat-treated bolt according to claim 1, wherein: in the second step, the heating temperature of the fine line is 800-900 ℃.
5. The method of manufacturing a non heat-treated bolt according to claim 1, wherein: and step three, the bolt blank is cooled to 450 +/-10 ℃ at the cooling rate of 16-18 ℃/s, and then is placed in the air to be naturally cooled to the normal temperature.
6. The method of manufacturing a non heat-treated bolt according to claim 1, wherein: the specification of the hot-rolled wire rod is phi 5.0-42.5 mm, and the specification of the fine wire processed by cold drawing is phi 4.2-40.0mm.
7. The method for manufacturing a non-heat-treated bolt according to claim 1, wherein: the metallographic structure of the bolt is sorbite.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211118147.1A CN115502324A (en) | 2022-09-14 | 2022-09-14 | Manufacturing method of non-quenched and tempered bolt |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211118147.1A CN115502324A (en) | 2022-09-14 | 2022-09-14 | Manufacturing method of non-quenched and tempered bolt |
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| CN115502324A true CN115502324A (en) | 2022-12-23 |
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| CN202211118147.1A Pending CN115502324A (en) | 2022-09-14 | 2022-09-14 | Manufacturing method of non-quenched and tempered bolt |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116904877A (en) * | 2023-06-29 | 2023-10-20 | 江阴兴澄合金材料有限公司 | Cold drawn steel wire for 10.9-grade non-quenched and tempered U-shaped bolt and manufacturing method thereof |
-
2022
- 2022-09-14 CN CN202211118147.1A patent/CN115502324A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116904877A (en) * | 2023-06-29 | 2023-10-20 | 江阴兴澄合金材料有限公司 | Cold drawn steel wire for 10.9-grade non-quenched and tempered U-shaped bolt and manufacturing method thereof |
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