CN110614373A - Production process for manufacturing textile machinery accessories by using powder metallurgy process - Google Patents
Production process for manufacturing textile machinery accessories by using powder metallurgy process Download PDFInfo
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- CN110614373A CN110614373A CN201911068379.9A CN201911068379A CN110614373A CN 110614373 A CN110614373 A CN 110614373A CN 201911068379 A CN201911068379 A CN 201911068379A CN 110614373 A CN110614373 A CN 110614373A
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- sintering
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- powder
- powder metallurgy
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/02—Compacting only
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/10—Sintering only
- B22F3/1003—Use of special medium during sintering, e.g. sintering aid
- B22F3/1007—Atmosphere
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/24—After-treatment of workpieces or articles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F5/00—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/24—After-treatment of workpieces or articles
- B22F2003/247—Removing material: carving, cleaning, grinding, hobbing, honing, lapping, polishing, milling, shaving, skiving, turning the surface
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- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Mechanical Engineering (AREA)
- Powder Metallurgy (AREA)
Abstract
The invention belongs to the technical field of textile machinery equipment accessories (roller sliding seats), in particular to a production process for manufacturing textile machinery accessories by using a powder metallurgy process, which aims at solving the problems that the appearance roughness of the existing roller sliding seat production process is poor, the machining lines are rough, the consistency of the size and the form and position tolerance of parts is relatively poor, and the assembly effect and the spinning quality of the whole machine are influenced, and provides the following scheme that S1: mixing materials: raw material powder with the specification types of 200-mesh iron powder, 200-mesh copper powder, 2000-mesh graphite and the like is mixed by using a special mixer according to a certain formula proportion. The invention provides a powder metallurgy processing and production technology, which changes the original product production technology and utilizes the powder metallurgy one-step forming technology to produce, thereby reducing the investment of subsequent machining procedures, improving the product quality and stability and improving the appearance quality of the product.
Description
Technical Field
The invention relates to the technical field of textile machinery equipment accessories (roller sliding seats), in particular to a production process for manufacturing textile machinery accessories by using a powder metallurgy process.
Background
With the rapid development of the textile machinery industry, the roller slide seat is taken as one of important parts in spinning equipment in the textile machinery, and has important influence on the assembly and the running stability of the spinning machine equipment and the spinning quality. The roller slide seat applied to spinning machinery at present is an iron casting, the material is generally HT200, the processing of the basic shape of the outline blank is finished through a casting process, and the shape and the whole size of a finished product are ensured by subsequent machining; the appearance roughness is poor, the machining lines are rough, the consistency of the sizes and form and position tolerances of parts is relatively poor, and the assembly effect and the spinning quality of the whole machine are influenced, so a production process for manufacturing textile machinery parts by using a powder metallurgy process is provided for solving the problems.
Disclosure of Invention
The invention aims to solve the problems that the roller sliding seat applied to spinning machinery at present in the prior art is an iron casting, the material is generally HT200, the processing of the basic shape of the outline blank is completed through a casting process, and the shape and the whole size of the finished product are ensured by subsequent machining; poor appearance roughness, rough machining lines, relatively poor consistency of part sizes and form and position tolerances and influence the assembly effect of the whole machine and the spinning quality, and provides a production process for manufacturing textile machinery parts by using a powder metallurgy process.
In order to achieve the purpose, the invention adopts the following technical scheme:
a production process for manufacturing textile machinery accessories by using a powder metallurgy process comprises the following steps:
s1: mixing materials: mixing raw material powder with specification types of 200-mesh iron powder, 200-mesh copper powder, 2000-mesh graphite and the like by using a special mixer according to a certain formula proportion;
s2: and (3) pressing and forming: placing the mixed material into a designated die and pressing and molding by using a mechanical press;
s3: sintering and hardening: orderly putting the pressed products into a high-temperature sintering furnace, and introducing inert protective gas into a sintering path to ensure that the whole sintering process is carried out in a closed environment without being oxidized;
s4: tapping threads: and (4) processing the sintering hardened product into a specified size by using corresponding mechanical equipment.
S5: surface finishing: processing and polishing the processed product;
s6: steam treatment: and (3) carrying out steam treatment on the iron-based part to form a layer of ferroferric oxide film on the surface of the part.
Preferably, in S1, the mixer can mix the raw material powders with specifications of 200 mesh iron powder, 200 mesh copper powder, 2000 mesh graphite, etc. sufficiently and uniformly, and meet the technical indexes of powder flowability, apparent density, compressibility, etc., and the formula material can meet the mechanical properties of gray iron material, such as tensile strength, etc., and meet the final use requirements.
Preferably, in S2, the product structure is reasonably designed according to factors such as formability, demolding, uniform density distribution, and convenience in mold filling according to the product formability structure, then the mold is mounted on a full-automatic mechanical press device, the molding height size and density control requirement of the corresponding mold are adjusted according to the forming process size, finally, the press forming of the product is automatically completed through actions such as automatic filling, pressing, demolding, discharging, and the like, and the pressed product is placed in a turnover appliance according to the requirement to be transferred to the next process.
Preferably, in S3, the powder metallurgy sintering is a high temperature treatment process for further combining the pressed compact or loose packed powder body to improve the strength and other properties, and the powder body undergoes a series of physicochemical changes during the sintering process, such as evaporation or volatilization of organic substances, elimination of adsorbed gas, elimination of stress, reduction of oxides on the surface of the powder particles, migration of substances between particles, recrystallization, grain growth, and the like, thereby increasing the crystal contact area between particles and even eliminating the pore shrinkage.
Preferably, in the step S3, the whole sintering process can be divided into three stages of preheating, sintering and cooling, selecting corresponding sintering equipment and sintering process according to material property of sintering material and mechanical property to be formed, wherein the preheating stage refers to the preparation stage of the pressed compact from charging to high-temperature sintering at 60-90 ℃, mainly eliminates stress, volatilizes organic matters and the like in the stage, the temperature of the sintering section is 1080-1250 ℃, the sintering time is about 30-45 minutes, during the process, copper powder particles are melted and form a certain liquid phase to be filled in particle gaps, pearlite and ferrite are formed along with the sintering, the alloyed structure of the material is really formed, the surface temperature of the product is reduced to below 60 ℃ by using circulating water in the cooling section, and the product is discharged from the furnace, at the moment, the surface of the product is silvery white, and the surface hardness is more than HRB 40.
Preferably, in S4, the realization of the corresponding structure and size is completed by using a numerical control lathe, a milling machine, a tapping machine, and other equipment according to the local unforgeable size of the product and the position that needs to be punched and tapped at the later stage.
Preferably, in S5, the processed product is placed in a finishing machine, and the finishing machine removes sharp edges and burrs on the surface of the product by using an eccentric vibration material and a stainless steel abrasive material, so as to meet the requirement of appearance.
Preferably, in the step S6, the cleaned part is placed in a steam treatment frame, and is placed in a steam treatment furnace, the treatment temperature is raised to 560-580 ℃, superheated steam is introduced to cause an oxidation reaction on the surface of the part, and finally an oxide layer film is formed on the surface of the product, the product after the steam treatment is blue-black, and the surface hardness reaches more than HRB 80.
In the invention, powder metallurgy is to fill powder particles into a preset forming die and press the powder particles into a (designed) shape and size (a blank has certain density and strength) by a press;
then, alloy hardening is carried out through high-temperature sintering, pearlite is formed in the structure and has certain hardness, then a thread tapping machine of the mounting hole and fine machining of the local part size are carried out, then the product is placed in a finishing machine to remove sharp edges, finally the product enters a steam treatment furnace to be subjected to steam treatment, so that an oxide layer is formed on the surface of the product, and finally the hardness and the strength of the product are formed.
The invention provides a powder metallurgy processing and production technology, which changes the original product production technology and utilizes the powder metallurgy one-step forming technology to produce, thereby reducing the investment of subsequent machining procedures, improving the product quality and stability and improving the appearance quality of the product.
Drawings
FIG. 1 is a schematic structural view of a formed product of the inventive process of the present invention;
FIG. 2 is a schematic structural diagram of a product formed by the process of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.
Referring to FIGS. 1-2; a production process for manufacturing textile machinery accessories by using a powder metallurgy process comprises the following steps:
s1: mixing materials: mixing raw material powder with specification types of 200-mesh iron powder, 200-mesh copper powder, 2000-mesh graphite and the like by using a special mixer according to a certain formula proportion;
s2: and (3) pressing and forming: placing the mixed material into a designated die and pressing and molding by using a mechanical press;
s3: sintering and hardening: orderly putting the pressed products into a high-temperature sintering furnace, and introducing inert protective gas into a sintering path to ensure that the whole sintering process is carried out in a closed environment without being oxidized;
s4: tapping threads: and (4) processing the sintering hardened product into a specified size by using corresponding mechanical equipment.
S5: surface finishing: processing and polishing the processed product;
s6: steam treatment: and (3) carrying out steam treatment on the iron-based part to form a layer of ferroferric oxide film on the surface of the part.
In this embodiment, in S1, the mixer can mix the raw material powders of 200 mesh iron powder, 200 mesh copper powder, 2000 mesh graphite, etc. fully and uniformly, and meet the technical indexes of powder flowability, loose density, compressibility, etc., the formula material can meet the mechanical properties of gray iron material such as tensile strength, etc., and meet the final use requirements, in S2, the product structure is reasonably designed according to the factors of formability, demoulding, uniform density distribution, convenient moulding, etc. according to the product formability structure, then the mould is installed on the full-automatic mechanical press equipment, the moulding height and density control requirements of the corresponding mould are adjusted according to the moulding process size, finally, the press moulding of the product is automatically completed through actions of automatic filling, pressing, demoulding, discharging, etc., the pressed product is placed in the transferring apparatus according to the requirements to be transferred to the next process, s3, powder metallurgy sintering is a high temperature treatment process for further combining pressed compact or loose powder to improve strength and other properties, the powder undergoes a series of physical and chemical changes in the sintering process, such as evaporation or volatilization of organic matters, elimination of adsorbed gas, elimination of stress, reduction of oxides on the surface of powder particles, migration of substances among particles, recrystallization, grain growth and the like, so that the crystal contact area among particles is increased, and the pores shrink or even disappear, S3, the whole sintering process can be divided into three stages, namely preheating, sintering and cooling, corresponding sintering equipment and sintering process are selected according to the material properties of the sintering material and the mechanical properties to be formed, the preheating stage refers to the preparation stage from the feeding of the pressed compact into a furnace to the high temperature sintering, the temperature is 60-90 ℃, and the stress elimination stage is mainly used in the high temperature treatment process, Volatilizing organic matter, sintering at 1080-1250 deg.c for 30-45 min, smelting copper powder to form certain liquid phase filled into the grain space, forming pearlite and ferrite, alloying material, cooling with circulating water to lower the surface temperature to below 60 deg.c, discharging the product with silvery white surface hardness over HRB40, S4, drilling and tapping in the required size, and S5, setting the product in a polishing machine to eliminate sharp edge and burr to meet the requirement, s6, putting the cleaned parts into a steam treatment frame, putting the parts into a steam treatment furnace, raising the treatment temperature to 560 ℃ and 580 ℃, introducing superheated steam, enabling the surfaces of the parts to generate oxidation reaction, and finally forming an oxide layer film on the surfaces of the products, wherein the products after the steam treatment are blue-black, and the surface hardness reaches above HRB 80.
In the embodiment, the powder metallurgy is to fill powder particles into a preset forming die, and press the powder particles into a (designed) shape and size (a blank has certain density and strength) through a press;
then, alloy hardening is carried out through high-temperature sintering, pearlite is formed in the structure and has certain hardness, then a thread tapping machine of the mounting hole and fine machining of the local part size are carried out, then the product is placed in a finishing machine to remove sharp edges, finally the product enters a steam treatment furnace to be subjected to steam treatment, so that an oxide layer is formed on the surface of the product, and finally the hardness and the strength of the product are formed.
The embodiment provides a powder metallurgy processing and production technology, which is characterized in that the production is carried out by utilizing a powder metallurgy one-step forming technology through changing the production technology of an original product, the investment of subsequent machining procedures is reduced, the product quality and stability are improved, and the appearance quality of the product is improved.
Compared with the prior roller sliding seat process, the roller sliding seat process of the embodiment has the advantage that the production efficiency is improved by 7.5-8.6% compared with the prior production efficiency.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be able to cover the technical scope of the present invention and the equivalent alternatives or modifications according to the technical solution and the inventive concept of the present invention within the technical scope of the present invention.
Claims (8)
1. A production process for manufacturing textile machinery accessories by using a powder metallurgy process is characterized by comprising the following steps:
s1: mixing materials: mixing raw material powder with specification types of 200-mesh iron powder, 200-mesh copper powder, 2000-mesh graphite and the like by using a special mixer according to a certain formula proportion;
s2: and (3) pressing and forming: placing the mixed material into a designated die and pressing and molding by using a mechanical press;
s3: sintering and hardening: orderly putting the pressed products into a high-temperature sintering furnace, and introducing inert protective gas into a sintering path to ensure that the whole sintering process is carried out in a closed environment without being oxidized;
s4: tapping threads: processing the sintered and hardened product into a size with a specified size by using corresponding mechanical equipment;
s5: surface finishing: processing and polishing the processed product;
s6: steam treatment: and (3) carrying out steam treatment on the iron-based part to form a layer of ferroferric oxide film on the surface of the part.
2. The process of claim 1, wherein in step S1, the mixer is used to mix the raw material powders of 200 mesh iron powder, 200 mesh copper powder and 2000 mesh graphite uniformly and fully, and to meet the specifications of powder flowability, bulk density and compressibility.
3. The production process for manufacturing textile machinery accessories by using the powder metallurgy process according to claim 1, wherein in the step S2, the reasonable design of the forming die is performed according to the factors of forming, demolding, uniform density distribution and convenient die filling on the product structure according to the product forming structure, then the die is installed on a full-automatic mechanical press device, the forming height size and density control requirement of the corresponding die are adjusted according to the forming process size, finally, the press forming of the product is automatically completed by actions of automatic filling, pressing, demolding, discharging and the like, and the pressed product is placed in a turnover appliance according to the requirement to be transferred to the next process.
4. The manufacturing process of claim 1, wherein in step S3, the powder metallurgy sintering is a high temperature process to further combine pressed compact or loose powder for strength and other properties, and the powder undergoes a series of physicochemical changes during sintering.
5. The process of claim 1, wherein in step S3, the whole sintering process includes three stages of preheating, sintering and cooling, and the sintering equipment and the sintering process are selected according to the material properties of the sintered material and the mechanical properties to be formed, wherein the preheating stage is a preparation stage from entering the furnace to entering the high temperature sintering, the temperature is 60-90 ℃, the sintering stage is 1080-1250 ℃, the sintering time is 30-45 minutes, during which the copper powder particles are melted and form a certain liquid phase to fill the particle voids, pearlite and ferrite are formed along with the sintering, the texture of the material alloying is actually formed, the cooling stage is to use the circulating water to reduce the surface temperature of the product to below 60 ℃ and to exit the furnace, and the surface of the product is silvery white, the surface hardness reaches more than HRB 40.
6. The production process for manufacturing the textile machinery accessory by the powder metallurgy process according to claim 1, wherein in the step S4, according to the local unforgeable size of the product and the position needing post-punching and tapping, the realization of the corresponding structure and size is completed by using a numerical control lathe, a milling machine and a tapping machine.
7. The manufacturing process of accessories for textile machinery according to claim 1, wherein in step S5, the finished product is placed in a finishing machine, and the finishing machine removes sharp burrs on the surface of the product by using eccentric vibration material and stainless steel abrasive.
8. The process as claimed in claim 1, wherein in step S6, the cleaned parts are placed in a steam treatment frame and placed in a steam treatment furnace, the treatment temperature is raised to 560 ℃ and 580 ℃, superheated steam is introduced to cause the oxidation reaction on the surface of the parts, and finally an oxide layer film is formed on the surface of the products, the products after the steam treatment are blue-black, and the surface hardness is higher than HRB 80.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911068379.9A CN110614373A (en) | 2019-11-05 | 2019-11-05 | Production process for manufacturing textile machinery accessories by using powder metallurgy process |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911068379.9A CN110614373A (en) | 2019-11-05 | 2019-11-05 | Production process for manufacturing textile machinery accessories by using powder metallurgy process |
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| CN110614373A true CN110614373A (en) | 2019-12-27 |
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| CN201911068379.9A Pending CN110614373A (en) | 2019-11-05 | 2019-11-05 | Production process for manufacturing textile machinery accessories by using powder metallurgy process |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111702167A (en) * | 2020-06-24 | 2020-09-25 | 重庆科利得精密机械工业有限公司 | Three-step mixing process for iron-based powder metallurgy |
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| KR100806229B1 (en) * | 2007-10-04 | 2008-02-22 | (주) 배명 | Selvage yarn processing unit of air jet loom |
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2019
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| CN101078141A (en) * | 2007-06-29 | 2007-11-28 | 山西鸿基实业有限公司 | Magnesium alloy roller slide |
| KR100806229B1 (en) * | 2007-10-04 | 2008-02-22 | (주) 배명 | Selvage yarn processing unit of air jet loom |
| CN102717082A (en) * | 2012-05-23 | 2012-10-10 | 马鞍山市华东粉末冶金厂 | Method for producing water pump half coupler by powder metallurgy |
| CN103785836A (en) * | 2012-10-29 | 2014-05-14 | 无锡荡口通和纺织机械厂 | Powder metallurgy process |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111702167A (en) * | 2020-06-24 | 2020-09-25 | 重庆科利得精密机械工业有限公司 | Three-step mixing process for iron-based powder metallurgy |
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Application publication date: 20191227 |
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