CN108819173B - Wear-resistant screw and manufacturing method thereof - Google Patents
Wear-resistant screw and manufacturing method thereof Download PDFInfo
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- CN108819173B CN108819173B CN201810614182.XA CN201810614182A CN108819173B CN 108819173 B CN108819173 B CN 108819173B CN 201810614182 A CN201810614182 A CN 201810614182A CN 108819173 B CN108819173 B CN 108819173B
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Abstract
A wear-resistant screw comprises a screw body (1) and a wear-resistant layer (5), wherein the wear-resistant layer (5) is a FeNiCrB alloy layer; the wear-resistant layer (5) is uniformly and concentrically fused on the surface layer of the rod body (1); the FeNiCrB alloy layer adopts FeNiCrB alloy with the following components: every 100 parts of FeNiCrB alloy comprises 8-15 parts of chromium, 8-10 parts of nickel, 3-4 parts of boron and the balance of iron by weight. The advantages are that: the wear-resistant layer is arranged on the outer surface of the rod body, the wear-resistant layer can improve the wear resistance of the screw edges and the spiral grooves, the service life of the wear-resistant screw rod is prolonged, the rod body is quenched in the process of adding the wear-resistant layer, the surface is more uniform and dense, the center of gravity is more stable in the using process, and the eccentric collapse is not easy to occur; the screw is machined in steps, operation of each step is simple, automatic operation can be achieved, operation precision is improved, drawing size requirements are met, the using effect is good, the tolerance range is gradually reduced, the drawing requirements are finally met, machining difficulty is reduced, and the rate of finished products is correspondingly improved.
Description
Technical Field
The invention relates to the technical field of screw manufacturing, in particular to a wear-resistant screw and a manufacturing method thereof.
Background
The traditional Chinese invention patent application with the application number of CN201310703986.4 named as 'high-wear-resistance iron boride alloy screw element for a double-screw machine and a manufacturing method thereof' discloses a high-wear-resistance iron boride alloy screw element for the double-screw machine, which comprises a body and an iron boride alloy layer; the iron boride alloy layer is uniformly and concentrically fused on the surface layer of the body, and the overall thickness of the iron boride alloy layer is 50-150 micrometers; the body is high-chromium high-carbon die steel, and the die steel is Cr12 MoV. The high-wear-resistance iron boride alloy screw element for the double-screw extruder provided by the invention is an iron boride alloy screw element for the double-screw extruder in the industries of plastics, LEDs, cables, food, feed, building materials and the like, has high wear resistance, can greatly reduce the manufacturing and application cost, and can greatly improve the production efficiency. However, the screw manufactured by the manufacturing method has poor wear resistance and short service life, so the manufacturing method needs further improvement.
Disclosure of Invention
The first technical problem to be solved by the present invention is to provide a wear-resistant screw rod with good wear resistance and long service life.
The technical scheme adopted by the invention for solving the technical problems is as follows: this wear-resisting screw rod, including the body of rod and wearing layer, its characterized in that: the wear-resistant layer is a FeNiCrB alloy layer; the wear-resistant layer is uniformly and concentrically fused on the surface layer of the rod body; the FeNiCrB alloy layer adopts FeNiCrB alloy with the following components in percentage by weight: every 100 parts of FeNiCrB alloy comprises 8-15 parts of chromium, 8-10 parts of nickel, 3-4 parts of boron and the balance of iron by weight.
As an improvement, the thickness of the FeNiCrB alloy layer is preferably 100-250 μm.
As an improvement, borax for accelerating the alloy melting speed can be preferably added into the FeNiCrB alloy, and 4-6 parts of borax are added into each 100 parts of the FeNiCrB alloy, wherein the parts are parts by weight.
The second technical problem to be solved by the present invention is to provide a manufacturing method for manufacturing a wear-resistant screw rod by using the above formula, aiming at the current state of the prior art, and the manufacturing method has the advantages of simple operation, high yield and excellent wear resistance of the manufactured wear-resistant screw rod.
The technical scheme adopted by the invention for solving the technical problems is as follows: the manufacturing method of the wear-resistant screw is characterized by comprising the following steps: comprises the following steps of (a) carrying out,
firstly, selecting a 38CrMoAL alloy rod as a rod body of a wear-resistant screw rod, and blanking according to the specification length;
heating the fed rod body to 900-950 ℃ in a quenching and tempering furnace, then quenching the rod body to 80-130 ℃, and then tempering the quenched rod body in a tempering furnace at 600-650 ℃, wherein the tempering time in the tempering furnace is calculated by heat preservation for 20-50 minutes per 25mm according to the diameter;
thirdly, processing a spiral groove and a screw edge on the tempered rod body to form a screw rough blank, wherein the outer diameter of the screw edge is 3-4 mm to negative tolerance;
feeding the screw rough blank into a heater for heating, wherein the heating temperature is 1150-1250 ℃, the FeNiCrB alloy is uniformly melted on the outer peripheral surface of the screw rough blank with the screw ridge and the spiral groove, the screw rough blank is subjected to heat preservation for 8-20 seconds after the melting is finished, and the screw rough blank is fed out of the heater after the heat preservation;
fifthly, placing the screw rough blank welded with the FeNiCrB alloy layer at the temperature of 600-650 ℃ and preserving heat for 2-4 hours;
sixthly, polishing the spiral groove of the screw rough blank after heat preservation until the depth of the spiral groove is processed to a positive tolerance of 0.03-0.05 mm according to the specification of a drawing; milling a key groove on the rough blank of the screw rod while polishing the spiral groove or after polishing the spiral groove to form a formed wear-resistant screw rod;
and seventhly, performing finish machining on the formed wear-resistant screw until the size of the wear-resistant screw reaches the drawing tolerance of-0.01 mm, and obtaining the finished screw.
In the third step, firstly, the blanked rod body is roughly processed to the positive tolerance of 1mm according to the specification of the drawing, and then, the spiral groove and the spiral ridge are processed, wherein the groove depth of the spiral groove is 1-1.5 mm to the positive tolerance according to the specification of the drawing.
And as an improvement, the dosage of the FeNiCrB alloy adopted in the fourth step is 1.05-1.1 times of the dosage of the required FeNiCrB alloy layer, the required chromium, nickel and boron are weighed according to the formula and are uniformly stirred, and then the iron powder and the borax are added into the stirred alloy powder.
And 5, as an improvement, in the fifth step, the wear-resistant screw rod with the key groove milled is sent into a gas nitriding furnace for surface nitriding treatment, the wear-resistant screw rod after nitriding treatment is naturally cooled to 30-50 ℃ in a vacuum furnace, and then the sixth step is carried out.
Further improvement, the specific process of the nitriding treatment is as follows: firstly, adding the wear-resistant screw rod with the key groove milled into a gas nitriding furnace; secondly, heating the wear-resistant screw to 500-530 ℃ in a nitrogen nitriding furnace filled with nitrogen, and keeping the temperature for 23-25 hours, wherein the decomposition rate of the nitrogen is controlled to be 20-28%; thirdly, continuously heating the wear-resistant screw subjected to the second heat preservation step to raise the temperature of the wear-resistant screw to 530-560 ℃, then controlling the decomposition rate of nitrogen in the nitriding furnace to be 50-55%, and preserving heat for 52-54 hours; and thirdly, continuously heating the wear-resistant screw rod subjected to heat preservation in the second step to 560-590 ℃, controlling the decomposition rate of nitrogen to be 90-95%, and preserving heat for 1-2 hours.
As an improvement, the polishing in the fifth step is specifically performed by polishing the wear-resistant screw through a diamond abrasive belt, and then performing fine grinding on the wear-resistant screw polished through the abrasive belt on the diamond abrasive belt.
And as an improvement, sampling and detecting the finished screw in the seventh step, keeping the ratio of the qualified screws with the thicknesses of the wear-resistant layers meeting the standard and the component ratios of the wear-resistant layers meeting the requirements to be 99 qualified screws/100 finished screws, coating antirust grease or paint on the surfaces of the qualified screws before warehousing, and packaging and warehousing.
Compared with the prior art, the invention has the advantages that: the wear-resistant layer is arranged on the outer surface of the rod body, the wear-resistant layer can improve the wear resistance of the screw edge and the spiral groove, the service life of the wear-resistant screw rod is prolonged, the rod body is quenched in the process of adding the wear-resistant layer, the surface is more uniform and dense, the center of gravity is more stable in the using process, and the eccentric collapse is not easy to occur; the screw is machined in steps, the operation of each step is simple, the automatic operation can be realized, the operation precision is improved, the drawing size requirement is met, the use effect is good, the tolerance range is gradually reduced, the drawing requirement is finally met, the machining difficulty is reduced, and the yield is correspondingly improved; the formula of the wear-resistant layer of the screw is simple in components, low in manufacturing cost and good in wear-resistant effect, the proportion of each component can be accurately determined by weighing, and the preparation is very convenient.
Drawings
FIG. 1 is a perspective view of an embodiment of the present invention;
FIG. 2 is a top view of FIG. 1;
FIG. 3 is a cross-sectional view taken along line A-A of FIG. 2;
fig. 4 is an enlarged view of a portion I in fig. 3.
Detailed Description
The invention is described in further detail below with reference to the accompanying examples.
As shown in fig. 1 to 4, the wear-resistant screw of the present embodiment includes a rod body 1 and a wear-resistant layer 5, where the wear-resistant layer 5 is a FeNiCrB alloy layer; the wear-resistant layer 5 is uniformly and concentrically fused on the surface layer of the rod body 1; the FeNiCrB alloy layer adopts FeNiCrB alloy with the following components in percentage by weight: every 100 parts of FeNiCrB alloy comprises 8-15 parts of chromium, 8-10 parts of nickel, 3-4 parts of boron and the balance of iron by weight. The thickness of the FeNiCrB alloy layer is 100-250 mu m. The FeNiCrB alloy is added with borax for accelerating the melting speed of the alloy, and each 100 parts of the FeNiCrB alloy is added with 4-6 parts of the borax by weight.
The manufacturing method of the wear-resistant screw rod according to the formula comprises the following steps,
firstly, selecting a 38CrMoAL alloy rod as a rod body 1 of the wear-resistant screw rod, and blanking according to the specification length;
secondly, heating the blanked rod body 1 to 900-950 ℃ in a quenching and tempering furnace, then quenching the rod body to 80-130 ℃, and then tempering the quenched rod body 1 in a tempering furnace at 600-650 ℃, wherein the tempering time in the tempering furnace is calculated by keeping the temperature of each 25mm for 20-50 minutes according to the diameter;
thirdly, processing a spiral groove 2 and a screw ridge 3 on the tempered rod body 1 to form a screw rough blank, wherein the outer diameter of the screw ridge 3 is 3-4 mm to the negative tolerance;
feeding the screw rough blank into a heater for heating, wherein the heating temperature is 1150-1250 ℃, the FeNiCrB alloy is uniformly melted on the outer peripheral surface of the screw rough blank where the screw ridge 3 and the spiral groove 2 are located, the screw rough blank is subjected to heat preservation for 8-20 seconds after the melting is finished, and the screw rough blank is fed out of the heater after the heat preservation;
fifthly, placing the screw rough blank welded with the FeNiCrB alloy layer at the temperature of 600-650 ℃ and preserving heat for 2-4 hours;
sixthly, polishing the screw rough blank subjected to heat preservation by using a spiral groove 2 until the groove depth of the spiral groove 2 is processed to a positive tolerance of 0.03-0.05 mm according to the specification of a drawing; milling a key groove 4 on the rough blank of the screw rod while polishing the spiral groove 2 or after polishing the spiral groove 2 to form a formed wear-resistant screw rod;
and seventhly, performing finish machining on the formed wear-resistant screw until the size of the wear-resistant screw reaches the drawing tolerance of-0.01 mm, and obtaining the finished screw. In the third step, the blanked rod body 1 is roughly processed to a positive tolerance of 1mm according to the specification of a drawing, then the spiral groove 2 and the spiral ridge 3 are processed, and the groove depth of the spiral groove 2 is 1-1.5 mm to the positive tolerance according to the specification of the drawing.
And step four, the dosage of the FeNiCrB alloy adopted is 1.05-1.1 times of the dosage of the required FeNiCrB alloy layer, the required chromium, nickel and boron are weighed according to the formula and are uniformly stirred, and then the iron powder and the borax are added into the stirred alloy powder. And the polishing in the fifth step is specifically carried out by polishing the wear-resistant screw rod through a diamond abrasive belt, and then carrying out fine grinding on the wear-resistant screw rod polished by the abrasive belt on a diamond abrasive wheel. Sampling and detecting the finished screw rods in the sixth step, keeping the ratio of the qualified screw rods with the thickness of the wear-resistant layer 5 meeting the standard and the component proportion of the wear-resistant layer 5 meeting the requirement to be 99 qualified screw rods/100 finished screw rods, coating antirust grease or paint on the surfaces of the qualified screw rods before warehousing, and packaging and warehousing.
And fifthly, conveying the wear-resistant screw rod with the key slot 4 milled into a gas nitriding furnace for surface nitriding treatment, naturally cooling the wear-resistant screw rod after nitriding treatment to 30-50 ℃ in a vacuum furnace, and then processing in the sixth step. The specific process of the nitriding treatment comprises the following steps: firstly, adding the wear-resistant screw rod with the key slot 4 milled into a gas nitriding furnace; secondly, heating the wear-resistant screw to 500-530 ℃ in a nitrogen nitriding furnace filled with nitrogen, and keeping the temperature for 23-25 hours, wherein the decomposition rate of the nitrogen is controlled to be 20-28%; thirdly, continuously heating the wear-resistant screw subjected to the second heat preservation step to raise the temperature of the wear-resistant screw to 530-560 ℃, then controlling the decomposition rate of nitrogen in the nitriding furnace to be 50-55%, and preserving heat for 52-54 hours; and thirdly, continuously heating the wear-resistant screw rod subjected to heat preservation in the second step to 560-590 ℃, controlling the decomposition rate of nitrogen to be 90-95%, and preserving heat for 1-2 hours.
Claims (8)
1. The utility model provides a wear-resisting screw rod, includes body of rod (1) and wearing layer (5), its characterized in that: the wear-resistant layer (5) is a FeNiCrB alloy layer; the wear-resistant layer (5) is uniformly and concentrically fused on the surface layer of the rod body (1); the FeNiCrB alloy layer adopts FeNiCrB alloy with the following components in percentage by weight: 8-15 parts of chromium, 8-10 parts of nickel and 3-4 parts of boron in every 100 parts of FeNiCrB alloy, 6 parts of borax for accelerating the melting speed of the alloy, and the balance of iron, wherein the thickness of the FeNiCrB alloy layer is 100-250 mu m; the parts are parts by weight.
2. A method of making a wear resistant screw according to claim 1, wherein: comprises the following steps of (a) carrying out,
firstly, selecting a 38CrMoAL alloy rod as a rod body (1) of a wear-resistant screw rod, and blanking according to the specification length;
secondly, heating the blanked rod body (1) to 900-950 ℃ in a quenching and tempering furnace, then quenching the rod body to 80-130 ℃, and then tempering the quenched rod body (1) in a tempering furnace at 600-650 ℃, wherein the tempering time in the tempering furnace is calculated by keeping the temperature for 20-50 minutes every 25mm according to the diameter;
thirdly, processing a spiral groove (2) and a screw ridge (3) on the tempered rod body (1) to form a screw rough blank, wherein the outer diameter of the screw ridge (3) has a negative tolerance of 3-4 mm;
feeding the screw rough blank into a heater for heating, wherein the heating temperature is 1150-1250 ℃, the FeNiCrB alloy is uniformly melted on the outer peripheral surface of the screw rough blank where the screw ridge (3) and the spiral groove (2) are located, after the melting is finished, the screw rough blank is kept warm for 8-20 seconds, and after the heat preservation, the screw rough blank is fed out of the heater;
fifthly, placing the screw rough blank welded with the FeNiCrB alloy layer at the temperature of 600-650 ℃ and preserving heat for 2-4 hours;
sixthly, polishing the screw rough blank subjected to heat preservation by using a spiral groove (2) until the groove depth of the spiral groove (2) is processed to a positive tolerance of 0.03-0.05 mm according to the specification of a drawing; milling a key groove (4) on the rough blank of the screw rod while polishing the spiral groove (2) or after polishing the spiral groove (2) to form a formed wear-resistant screw rod;
and seventhly, performing finish machining on the formed wear-resistant screw until the size of the wear-resistant screw reaches the drawing tolerance of-0.01 mm, and obtaining the finished screw.
3. The method of manufacturing according to claim 2, wherein: in the third step, the blanked rod body (1) is roughly processed to the positive tolerance of 1mm according to the specification of a drawing, then the spiral groove (2) and the spiral ridge (3) are processed, and the groove depth of the spiral groove (2) is 1-1.5 mm to the positive tolerance according to the specification of the drawing.
4. The method of manufacturing according to claim 3, wherein: and step four, the dosage of the FeNiCrB alloy adopted is 1.05-1.1 times of the dosage of the required FeNiCrB alloy layer, the required chromium, nickel and boron are weighed according to the formula and are uniformly stirred, and then the iron powder and the borax are added into the stirred alloy powder.
5. The method of manufacturing according to claim 3, wherein: and fifthly, conveying the wear-resistant screw rod with the key groove (4) milled into a gas nitriding furnace for surface nitriding treatment, naturally cooling the wear-resistant screw rod after nitriding treatment to 30-50 ℃ in a vacuum furnace, and then processing in the sixth step.
6. The method of manufacturing according to claim 5, wherein: the specific process of the nitriding treatment comprises the following steps: firstly, adding the wear-resistant screw rod with the key groove (4) milled into a gas nitriding furnace; secondly, heating the wear-resistant screw to 500-530 ℃ in a nitrogen nitriding furnace filled with nitrogen, and keeping the temperature for 23-25 hours, wherein the decomposition rate of the nitrogen is controlled to be 20-28%; thirdly, continuously heating the wear-resistant screw subjected to the second heat preservation step to raise the temperature of the wear-resistant screw to 530-560 ℃, then controlling the decomposition rate of nitrogen in the nitriding furnace to be 50-55%, and preserving heat for 52-54 hours; and thirdly, continuously heating the wear-resistant screw rod subjected to heat preservation in the second step to 560-590 ℃, controlling the decomposition rate of nitrogen to be 90-95%, and preserving heat for 1-2 hours.
7. The method of manufacturing according to claim 2, wherein: and the polishing in the fifth step is specifically carried out by polishing the wear-resistant screw rod through a diamond abrasive belt, and then carrying out fine grinding on the wear-resistant screw rod polished by the abrasive belt on a diamond abrasive wheel.
8. The method of manufacturing according to claim 2, wherein: sampling and detecting the finished screw rods in the seventh step, keeping the ratio of the qualified screw rods with the thickness of the wear-resistant layer (5) meeting the standard and the component proportion of the wear-resistant layer (5) meeting the requirement as 99 qualified screw rods/100 finished screw rods, coating antirust grease or paint on the surfaces of the qualified screw rods before warehousing, and packaging and warehousing.
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| CN110116490A (en) * | 2019-04-18 | 2019-08-13 | 海天塑机集团有限公司 | A kind of screw in injection molding machine and preparation method thereof |
| CN110126229A (en) * | 2019-05-20 | 2019-08-16 | 宁波全泰环保科技有限公司 | A kind of efficiently plasticizing, anti-carbon deposition PVC film bolt special |
| CN113523266A (en) * | 2020-04-14 | 2021-10-22 | 江苏友和工具有限公司 | Ceramic wafer and processing technology thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000303140A (en) * | 1999-04-19 | 2000-10-31 | Daido Steel Co Ltd | Steel for plastic molding die |
| CN102343505A (en) * | 2011-08-10 | 2012-02-08 | 周建军 | Manufacturing method of bimetal screw rod |
| CN102343503A (en) * | 2011-08-10 | 2012-02-08 | 周建军 | Machine barrel fabrication method |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000303140A (en) * | 1999-04-19 | 2000-10-31 | Daido Steel Co Ltd | Steel for plastic molding die |
| CN102343505A (en) * | 2011-08-10 | 2012-02-08 | 周建军 | Manufacturing method of bimetal screw rod |
| CN102343503A (en) * | 2011-08-10 | 2012-02-08 | 周建军 | Machine barrel fabrication method |
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